STMicroelectronics AVAS User Manual

UM2719

User manual

AVAS architecture based on AutoDevKit

Introduction

The AutoDevKit Acoustic Vehicle Alerting System (AVAS) consists of an AEK-MCU-C1MLIT1 Discovery board, an AEK-AUD-

D903V1 evaluation board, and appropriate speakers. The AEK-MCU-C1MLIT1 board MCU monitors and controls the FDA903D

power amplifier on the AEK-AUD-D903V1 board via I²C and I²S serial interfaces and GPIOs.

The MCU board and the audio board can be wired together directly or via a connector board designed to simplify the process.

The AEK-MCU-C1MLIT1 board is supplied 5 V through its mini-USB connector, while the AEK-AUD-D903V1 can either be
supplied low voltage (from 3.3 V to 18 V) or standard voltage (from 5 V to 18 V).

Figure 1. AVAS system AutoDevKit control board and audio board

The hardware is fully supported by a software ecosystem, which includes SPC5-STUDIO development environment, SPC5-

UDESTK-SW software for debugging and STSW-AUTODEVKIT Eclipse plugin containing AEK-AUD-D903V1 driver and sample

application codes.

UM2719 - Rev 3 - April 2021
For further information contact your local STMicroelectronics sales office.

www.st.com

1 AVAS system hardware

Figure 2. AVAS demo hardware and connections

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AVAS system hardware

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page 2/60

AEK-MCU-C1MLIT1 Discovery board audio support

2 AEK-MCU-C1MLIT1 Discovery board audio support

The AEK-MCU-C1MLIT1 Discovery evaluation board features the SPC582B60E1 automotive microcontroller with
high performance e200z2 single core 32-bit CPU with 80MHz clock, 1088 KB Flash and 96 KB SRAM in an
eTQFP64 package. The I²S (simulated by an SPI port), I²C port and GPIOs provide the necessary signal and
communication lines to control a class D power amplifier.

The board also integrates a programmer/debugger interface based on the UDE PLS software, allowing the user
to program the microcontroller and debug software applications. The integrated debugger software is available
through ST's free integrated development environment, SPC5-STUDIO. To download the debugger software and
to activate the license, refer to the PLS website.

Note: Arduino connectors are not mounted on this board and are not required for the audio application.

Figure 3. AEK-MCU-C1MLIT1 Discovery board components

1. PLS programmer/debugger

2. USB power connector to supply 5V and load firmware

3. User interface with three LEDs and two buttons

4. 32-bit SPC582B60E1 MCU

5. CN10 19x2 connector for access to I²C and I²S ports and GPIOs

6. CN7 11x2 connector for access to I²S ports and GPIOs

7. CN6 connector allows supplying the board with different external voltage (3.3 V, 5 V or 12 V)

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UM2719 - Rev 3

The SPC582B60E1 microcontroller includes the following additional features:

• 1088 KB (1024 KB code flash + 64 KB data flash) on-chip flash memory: supports read during program and
erase operations, and multiple blocks allowing EEPROM emulation

• Comprehensive new generation ASIL-B safety concept:

– ASIL-B of ISO 26262 – FCCU for collection and reaction to failure notifications

– Memory Error Management Unit (MEMU) for collection and reporting of error events in memories.

• 1 enhanced 12-bit SAR analog-to-digital converter:

– Up to 27 channels (two channels are used in the AVAS application for sound volume and acceleration)

– enhanced diagnostic feature.

page 3/60

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I²S bus interface on the SPC582B60E1 microcontroller

• I²C interface

4 serial peripheral interface (DSPI) modules (a DSPI is used in the AVAS Demo to simulate the I²S bus

•
interface).

2.1 I²S bus interface on the SPC582B60E1 microcontroller

The FDA903D audio amp receives the audio signal from the flash blocks of the SPC582B60E1 via the I²S bus.
This interface can transmit two different audio channels on the same data line. As SPC5 microcontrollers do not
have a native I²S interface, an emulation through the DSPI protocol is implemented.

2.1.1 I²S protocol details

The I²S bus consists of the following lines:

I2S SCL The clock signal frequency is the product of the sampling frequency and the number of bits

transmitted.

I2S DATA The transmitted data are coded in two's complement, and the MSB (Most Significant Bit) is

therefore in the first position of each word. The data word is composed of 32 bits.

Note: The device only processes the first 24 most significant bits and disregards the least significant 8 bits.

I2S WS The Word Select signal is synchronized with the sampling frequency. Its digital value identifies

the transmission channel (0 = right channel, 1 = left channel).

2.1.2 I²S emulation on DSPI for SPC5 MCU control of FDA903D amplifier

The FDA903D power amplifier allows audio playback at the following sampling frequencies:

•

44.1 kHz

• 48 kHz

• 96 kHz

• 192 kHz

The maximum DSPI clock limit can only support the lowest frequency (fs = 44.1 kHz).

DSPI is a synchronous serial communication interface primarily used for short-distance communication in
embedded systems. This interface is based on four signals:

SCLK: the serial clock signal from the master (the microcontroller in our application)

MOSI: the serial data from the master to the slave (the FDA903D in our case)

MISO: the serial data from the slave to the master

CS: selects which slave chip receives the message from the master

DSPI emulation of the I²S interface is therefore obtained through the following associations and parameter values:

•

I2S DATA → DSPI MOSI

– 32-bit data word

• I2S WS → DSPI CS

– varies the channel (right or left) according to the fs (sampling frequency).

• I2S SCLK → DPSI SCLK

– Frequency = n

= 2.822MHz .

• I2S TEST → DSPI MISO

– This additional signal allows the FDA903D to send real-time current sensing information to the

microcontroller and to a DSP for sound processing.

umberofcℎannels × numberofbitsinaword × samplingfrequency = 2x32x44.1kHz

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page 4/60

Figure 4. Standard I²S data format

1 / (64 x fs)

I2Sclk

I2Sws

I2SdataLeft channel Right channel

1 / fs

1 / (2 x fs) 1 / (2 x fs)

T

SCK

I2S SCL
I2S CR
I2S SDA
I2S WS

• MCU DSPI0 port access via four CN10 connector pins

• MCU has four DSPI ports

Figure 5. Connector CN10 pins for DSPI0

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I²S bus interface on the SPC582B60E1 microcontroller

RELATED LINKS

Refer to TN1296: "I²S emulation on DSPI" for more information about emulating the I²S protocol

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page 5/60

=

=

=

Data

Subaddrs

Address

Address

SubaddressAS A

Data

P

DATA

ADDR

DATA DATA DATA

SUB A

DATA

SUB A

DATA

SUB A

DATA

SUB A

DATA

SUB A

ADDR ADDR

ADDR ADDR ADDR ADDR ADDR

SUB ASUB ASUB A

UM2719

I²C bus interface on the SPC582B60E1 microcontroller

2.2 I²C bus interface on the SPC582B60E1 microcontroller

The I²C interface is used to control, program and request information from the audio amp. Data transmission from

SPC582B60E1 to the FDA903D

and SCL lines.

Note: According to the I²C protocol, it is mandatory to insert pull-up resistors to positive supply voltage on the SDA and

SCL lines.

[S] Start bit
Chip address byte
Sub-address byte
[data] n-byte + Acknowledge bit
[P] Stop bit

and vice versa takes place through the two-wire I²C bus interface for the SDA

Figure 6. I²C typical data format

The AEK-MCU-C1MLIT1 provides I²C port access through two pins on the CN10 connector shown in the figure

.

below

The discovery board has a single dedicated I²C port. Additional ports can be added by emulating the I²C protocol
via software to configure a GPIO pin for I²C SCL and another pin for I²C SDA.

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page 6/60

I2C SCL
I2C SDA

I²C bus interface on the SPC582B60E1 microcontroller

Figure 7. Connector CN10 pins dedicated to I²C

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UM2719

AEK-AUD-D903V1 evaluation board for automotive power amplifier

3 AEK-AUD-D903V1 evaluation board for automotive power amplifier

The AEK-AUD-D903V1 is designed to allow evaluation and application development based on the embedded

FDA903D automotive digital class D power amplifier in a PowerSSO-36 slug-down package.

Figure 8. AEK-AUD-D903V1 main components and interfaces

1. Output channel; 2. FDA903D power amplifier; 3. Power supply connector

4. Enable and HW mute pins: [EN1 to EN4]: 4 pins can be configured to switch on the amplifier and assign it on of 7 possible an

I²C addresses, [MUTE]: allows MUTE setting control of the power amplifier through a GPIO

5. I²C interface: [I2C SCL]: I2C clock line, [I2C SDA]: I2C data line

6. I²S interface: [I2S SCL]: I2S clock line, [I2S WS]: I2S Word select line, [I2S SDA]: digital input, [I2S CR]: I2S Output test

current, [GND]

2

1

3

4 5 6

The FDA903D power amplifier can be configured through its I²C bus interface and the device includes the
following diagnostics suite designed for automotive applications:

• open load in play detection

• DC diagnostic in MUTE to monitor the load status

• short to V

• digital Input Offset detection

• output Voltage Offset detection

• output Current Offset detection

• thermal protection

The FDA903D features a configurable power limiting function and can be optionally operated in legacy mode
without I²C communication.

/ GND diagnostic

CC

3.1 FDA903D finite state machine

The FDA903D finite state machine (FSM) describes how the device reacts to system and user inputs.

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Figure 9. FDA903D state machine

Stand By

Diag Vcc/Gnd

ECO-mode

Mute

Diag DC

Dump

Play

Enables set

AND

I2C programmed for the first

time

No short to Vcc/Gnd

condition STABLE for at least

90ms

I2C cmd:

“Diag DC start”

Diagnostic DC end

I2C cmd:

“PLAY”

Vcc over Overvoltage

shutdown limit

Enables = "0000"

OR

Vcc for system reset

OR

90ms Short to Vcc/Gnd check

Short to Vcc/Gnd present

(even for one instant)

I2C cmd:

“PWM ON”

I2C cmd:

“PWM OFF”

I2C cmd: "MUTE"

OR

Automatic mute

condition present

Vcc under

Overvoltage

shutdown limit

Overcurrent protection

OR

UVLO present

OR

Thermal shutdown

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FDA903D finite state machine

The initial standby state of the device cannot be exited until the I²C interface has been correctly enabled by
providing the correct supply voltage, the I²S clock, the I²S data and a valid combination of enable pins in order to
determine the I²C device address.

Standby

Amplifier ON address 1 = ‘1110000’ 0 1 0 0

Amplifier ON address 2 = ‘1110001’ 1 1 0 0

Amplifier ON address 3 = ‘1110010’ 0 0 1 0

Amplifier ON address 4 = ‘1110011’ 0 1 1 0

Amplifier ON address 5 = ‘1110100’ 0 1 0 1

Amplifier ON address 6 = ‘1110101’ 1 1 0 1

Amplifier ON address 7 = ‘1110110’ 0 0 1 1

Amplifier ON address 8 = ‘1110111’ 0 1 1 1

Configuration

Table 1. I²C device address combinations

Pin

Enable 1 Enable 2 Enable 3 Enable 4

0 0 0 0

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UM2719

FDA903D I²S protocol

When a valid combination of Enable 1/2/3/4 is recognized, the device turns on all the internal supply voltages
and outputs are biased to VCC

instruction. A return to the Standby condition (all the enable pins set to 0) resets of the amplifier. The finite state
machine shows that a reset is also triggered if PLL is not locked, I²S is missing or not correct, or VCC is removed.

There are also four possible legacy mode combinations for device operation without using the I²C interface.

/ 2. The internal I²C registers are preset in the default condition until the I²C next

Table 2. Legacy mode Enable configurations

Configuration

Legacy mode: low voltage mode; in-phase

Legacy mode: low voltage mode; out-phase 1 1 1 1

Legacy mode: standard voltage mode; in-phase 1 0 0 0

Legacy mode: standard voltage mode; out-phase 1 0 0 1

Enable 1 Enable 2 Enable 3 Enable 4

1 1 1 0

Pins

Note: FDA903D can only work in I²C slave mode; any combination other than those indicated are invalid.

3.1.1 FDA903D FSM state descriptions

Standby The ENABLEx pins set the I²C addresses and start up the system; if ENABLE1/2/3/4 are all

low ("0000"), then the FDA903D is of
consumption is limited.

Diagnostic Vcc-Gnd This state checks the device is in a safe operating condition, with no short to ground (Gnd),

short to VCC, overcurrent, undervoltage (UVLO
to the next Eco-mode if none of these faults occur for at least 90 ms. A stable fault is

communicated to the user via I²C messages after 90 ms. While in Diagnostic Vcc-Gnd state,
FDA903D can receive all the I²C commands but will not turn the PWM on.

ECO-mode The amplifier is fully operational and can receive and execute any valid command. Output

switching is disabled for low power consumption. The device can move from ECO-mode to
the MUTE state in order to activate switching within about 1 ms and without experiencing
POP-noise. This facilitates fast transition from ECO-mode to PLA

MUTE The FSM transitions from ECO-mode to the MUTE state through the I²C command to turn on

PWM. The MUTE state allows quick transition to PLA

PLAY The FSM transitions to this state from MUTE via the I²C “PLAY” command, and the same status

register bit governs the return from PLA
low battery mute, high battery mute, hardware mute pin and thermal mute automatically return
the amplifier to the MUTE state.

Diag DC This state starts the DC diagnostic routine to detect the load connection status and returns to

the MUTE state when the routine has finished.

Note: I²C commands performed by the user are executed via the I²C protocol by modifying the device register settings.

f, the outputs remain biased to ground and the current

), or thermal shutdown. The FDA903D

Vcc

moves

Y.

Y and diagnostic states.

Y back to MUTE. Certain external conditions such as

RELATED LINKS

Refer to the FAD903 datasheet for more information regarding its state machine

3.2 FDA903D I²S protocol

Audio data is transmitted to the power amplifier via the I²S protocol. The 32-bit data word is in two's complement
representation starting from the MSB. The device only processes the first 24 most significant bits and disregards
the 8 least significant bits.

Note:

UM2719 - Rev 3

Besides the standard I²S used in our demo, the FDA903D device also supports Time Division Multiplexing mode
(TDM).

page 10/60

I2S CURRENT TEST

UM2719

FDA903D I²C protocol

The FDA903D internal PLL locks on the I²S clock line signal frequency, which is why it is important to configure
the I²S bus appropriately. When the I²S clock is missing or corrupted, the PLL unlocks and the device is forced
into a standby state.

Figure 10. I²S (DSPI) connection in AEK-AUD-D903V1

I2S CLOCK LINE
I2S WS LINE

I2S DATA LINE

3.3 FDA903D I²C protocol

The DATA and SCLK wires for the I²C protocol are used to communicate, control and manage the FDA903D.
Connection between the I²C microcontroller port and I²C power amplifier pins on the AEK-AUD-D903V1 is
provided by the pins on the connector shown below.

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page 11/60

Figure 11. I²C connection in AEK-AUD-D903V1

I2C CLOCK LINE

I2C DATA LINE

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FDA903D I²C protocol

The power amplifier FDA903D is controlled with appropriate read and write operations on Instruction Bytes
registers (from IB0 to IB14) performed with the I2C protocol. Additional Data Bytes registers (from DB0 to DB6) in
the device record the state of the amplifier.

Writing to the instruction registers and reading from the device status registers are the fundamental elements of
device management.

3.3.1 I²C protocol writing procedure

Communication through the I²C protocol takes place via a well-defined sequence of bit packages: start bit →
recipient address → acknowledge bit → sub-address → acknowledge bit → actual data → stop bit.

The amplifier address is chosen from eight possible enable pins combinations that represent eight corresponding
addresses. For example, to assign I²C address1 = “1110000” to the device, enable pin 2 is set high (Enable 2 =
“1”) and enable pins 1,3 and 4 are set low (Enable1 = “0”, Enable3 = “0”, Enable4 = “0”).

Configuration

Standby

Amplifier ON address 1 = ‘1110000’ 0 1 0 0

Amplifier ON address 2 = ‘1110001’ 1 1 0 0

Amplifier ON address 3 = ‘1110010’ 0 0 1 0

Amplifier ON address 4 = ‘1110011’ 0 1 1 0

Table 3. I²C address 1 selection

Pin

Enable 1 Enable 2 Enable 3 Enable 4

0 0 0 0

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page 12/60

ENABLE 1
ENABLE 2
ENABLE 3

ENABLE 4

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FDA903D I²C protocol

Configuration

Amplifier ON address 5 = ‘1110100’

Amplifier ON address 6 = ‘1110101’ 1 1 0 1

Amplifier ON address 7 = ‘1110110’ 0 0 1 1

Amplifier ON address 8 = ‘1110111’ 0 1 1 1

The connector on the AEK-AUD-D903V1 provide access to the four enable pins by four corresponding GPIO pins
on the microcontroller.

Important: Close J2 connector pins with jumpers.

Figure 12. ENABLE pin locations on the connector

Pin

Enable 1 Enable 2 Enable 3 Enable 4

0 1 0 1

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The subaddress is assigned according to the IB register to be written, as shown in the following table.

Table 4. Subaddress association

Register name Corresponding Subaddress

IB0 I0000001

IB1 I0000010

page 13/60

UM2719

FDA903D I²C protocol

Register name Corresponding Subaddress

IB2 I0000011

IB3 I0000100

IB4 I0000101

IB5 I0000110

IB6 I0000111

IB7 I0001000

IB8 I0001001

IB9 I0001010

IB10 I0001011

IB11 I0001100

IB12 I0001101

IB13 I0001110

IB14 I0001111

In the above table, bit 7 of the subaddress is the letter “I” to represent the possibility of having an incremental
writing procedure. If the “I” bit is set to 1, the write operation is performed from the corresponding register and all
consecutive ones with a unique flow of data from I²C. The process can involve all registers or can be interrupted
by a stop bit received from I²C.

The data bits carry the actual information required to control the power amplifier.

3.3.2 I²C protocol: reading procedure

The reading procedure consists of the device address (sent by master) and the data (sent by slave).

When a reading procedure is performed, the first register read is the last addressed in a previous access to I²C
peripheral. Hence, the reading of a register is enabled by a write action (a write interrupted after the sub-address
is sent) to specify which register must be read. The following figure shows the complete procedure to read a
specific register where:

1. The master performs a write action by sending only the device address and the subaddress; the
transmission must be interrupted with the stop condition after the subaddress.

2. The master starts a new communication by sending the device address and the FDA903D slave responds
by sending the data bits.

3. The read communication is ended by the master which sends a stop condition preceded by a not­acknowledge.

Figure 14. Read operation required data

Alternatively, performing a start immediately after the stop condition can be used to generate the repeated start
condition (Sr), which also keeps busy the I²C bus until the stop is reached.

Figure 13. Read operation packet

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Figure 15. Read operation with repeated start condition

page 14/60

3.3.3 IB registers in I²C

The microcontroller accesses all amplifier functionality through the IB registers.

T

able 5. IB register map

IB register map

D7 D6 D5 D4 D3 D2 D1 D0

IB0 D7: enable/disable writing on IB registers

D6-D5: enable/disable the I²S standard protocol for transmitting the digital input

D4-D1: choose between right or left channel

DO: select between low voltage and standard voltage modes

IB1 D7-D6: select the I²S WS

D4-D3: select the PWM switching frequency based on the I²S WS value

D2: select between PWM amplifier dithered or not dithered

DO: select between PWM in phase or out of phase

IB2 D7-D6: establish the short to supply diagnostic timing

D4: activate/deactivate the low radiation function

D3-D0: enable and configure the amplifier power limiter

IB3 D5: enable/disable output voltage offset detector

D4: enable/disable input of

D3: enable/disable output current offset detector

D2: enable/disable high pass filter in DAC amplifier DAC

D1: enable/disable noise gating

D0: enable/disable open load in play detection

IB4 D7: enable CDDIAG to report presence of output voltage offset

D6-D4: enable CDDIAG to report temperature warnings

D3: enable CDDIAG to report overcurrent faults

D2: enable CDDIAG to report input of

D1: enable CDDIAG to report short to VCC or to Gnd fault

fset detector

fset

UM2719

FDA903D I²C protocol

D0: enable CDDIAG to report high voltage Mute fault

IB5 D7: enable CDDIAG to report undervoltage fault

D6: enable CDDIAG to report thermal shutdown fault

D5-4: enable CDDIAG to report PWM pulse skipping

IB6 D7-D6: establish MUTE timing setup

D5: select audio signal gain control

D4: choose between standard gain or low gain

IB7 D7-D6: select the diagnostic ramp time

D5-D4: select the diagnostic hold time

D1: choose between data generated on I²S clock falling edge or rising edge

D0: select the current sensing protocol configuration

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UM2719

FDA903D I²C protocol

IB8 D7-D6: set the full current sensing scale

D5: turn on/of

D4: enable the DC Diagnostic

D3-D1: configure the I²S CR pin

D0: put the amplifier in MUTE/PLAY

IB9 D4: enable/disable the watchdog for word select management

IB10 D7: set short load impedance threshold for DC diagnostic

D6: set open load impedance threshold for DC diagnostic and open load in play

D4-D3: configure the output current of

IB11 D5-D4: select the overcurrent protection level

D3: select between default PWM or PWM Slow slope

IB12 D7: select between standard thermal warning or thermal warning shift - 15 °C

IB13 D6: select whether digital mute is enabled or disabled in PLAY when Start Analog Mute without

thermal warnings occurs

IB14: D4: set feedback on LC filter/Out

D3-D1: configure the LC filter setup

D0: select whether or not setup is programmed via 1²C

f the PWM

fset detector threshold

3.3.4 DB registers in I²C

DB registers allow the microcontroller to monitor the status and operation of the power amplifier.

T

able 6. DB register map

DB register map

D7 D6 D5 D4 D3 D2 D1 D0

DB0 D7: indicates whether an offset at input is present

D6: indicates whether the current of

D5: indicates whether an offset at current offset is present

D3: indicates whether an offset at voltage offset is present

D2: indicates whether the open load in play test has ended

D1: indicates whether the open load in play test is valid

Do: indicates whether an open load is present or not

DB1 D7-D4: indicates whether the thermal warning is active

D3: indicates whether the PLL is locked

D2: indicates whether an undervoltage UVLOALL has been detected

D1: indicates whether an overvoltage shutdown has been detected

D0: indicates whether PWM pulse skipping has been detected

fset test has ended and if it is valid

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DB2 D7: indicates whether the DC diagnostic pulse has ended

D6: indicates whether the DC diagnostic is valid

D5: indicates whether the overcurrent protection has been activated

D4: indicates when a short load on channel occurs

D3: indicates when a short to V

on channel occurs

CC

D2: indicates when a short to Gnd on channel occurs

D1: indicates when an open load on channel occurs

D0: indicates whether the channel is in MUTE or in PLAY

DB3 Reserved for DC Diagnostic Error codes

DB4 Register is reserved for Channel Current Sensing (1O - 8)

DB5 Register is reserved for Channel Current Sensing (7 - 0)

DB6 D7: indicates whether the high voltage mute has started

D6: indicates whether an undervoltage UVLOV

has been detected

CC

D5: indicates whether a thermal shutdown has been detected

D4: indicates whether the analog mute is started

D2: indicates whether the watchdog for word select occurs

D1: indicates whether an error frame occurs

UM2719

Potentiometers

3.3.5 Driver

A driver has been developed to allow the user to monitor and control the amplifier without engaging in tedious IB
and DB register read and write operations associated with a task.

3.4 Potentiometers

The AVAS system includes two potentiometers to help simulate the sound of a car engine: one to simulate the
accelerator pedal and another to adjust the sound volume. The potentiometers are powered through two supply
voltages (5V and 3.3V) from the AEK-MCU-C1MLIT1 control board via female connector CN6 or male connector
CN7.

Our system uses the potentiometer as a voltage divider to obtain a manually adjustable output voltage from
a fixed input voltage applied across the two ends of the potentiometer. It is formed by an insulating cylinder
on which a metal wire is wound, and the two ends are connected to two terminals. One of these terminals is
connected to a sliding contact that runs the length of the cylinder. The operation is equivalent to a pair of resistors
in series whose total value is constant, but individually variable according to the position of the sliding contact.

Figure 16. Linear potentiometer circuit

UM2719 - Rev 3

Considering RL an open, we have the voltage on RT2 equal to the power supply voltage of the potentiometer



multiplied by

2

, and since this ratio is equal to that of LT2 (R





resistor length) on LT (total resistor length), we

T2

see that the output voltage of the potentiometer is a function of the cursor position.

page 17/60

Successive approximation analog-to-digital converter (SARADC)

V*L

V2=

T2

L

T

It is possible to implement speed and volume control by directly relating these variables to the output voltage of a
potentiometer

. The analog output of the potentiometers are converted into discrete values by the SPC582B60E1

microcontroller ADCs.

3.5 Successive approximation analog-to-digital converter (SARADC)

Two of the 27 SARADC channels on the AEK-MCU-C1MLIT1 control board microcontroller are used to convert
the potentiometer speed and volume signals into digital quantities through the connector CN7.

Note:

These signals can also be routed through CN11.

Figure 17. Potentiometer connections

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(1)

3.6 Stereo mode

In order to produce stereo audio, the system requires a second AEK-AUD-D903V1 board to occupy both the left
and right channels available on the I²S DA

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TA line.

page 18/60

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Stereo mode

Figure 18. A

VAS system for two stereo sound

The connection of a second audio board will involve the following modifications to the AVAS system:

The I²C interface is shared, so the I2C SCL clock line and the I2C DATA line are connected to both

•

AEK-AUD-D903V1 audio boards.

• The I²S interface is also shared as the lines (I2S SCLK, I2S WS and I2S DATA) are also used by the second
amp. The right channel and the left channel travel on the same line, and the I2S WS distinguishes the
information for the right channel and the left channel.

• The I²C communication between the microcontroller (master) and the two amplifiers (slaves) are
distinguished by the addresses that identify the two devices.

• The address that identifies each of the two amplifiers is obtained through a combination of the four enables,
so eight GPIOs are required in total.

This AEK-MCU-C1MLIT1 control board has a copy of the male CN7 and CN10 connectors on the back of the
board, which makes it relatively easy to split the connections for the I²C and I²S interfaces between the two amps.

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page 19/60

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Stereo mode

Figure 19. AEK-MCU-C1MLIT1 seen on both sides

Even though it would normally take eight GPIOs to assign addresses to the two amplifiers, we can use the copy
of the connectors on the back side of the control board to halve the number of GPIOs. T
combinations that have the same number of pins to put high ("1").

o do this, we use two

Table 7. Comparison of pin settings for addresses 1 and 3

Configuration

Amplifier ON address 1 = ‘1110000’

Amplifier ON address 3 = ‘1110010’ 0 0 1 0

Enable 1 Enable 2 Enable 3 Enable 4

0 1 0 0

Pin

In the above example, where address 1 and address 3 have the same number of high and low pins, it is evident
that we can use the same GPIOs to create the two necessary combinations by connecting the GPIO high (“1”)
to Enable 2 of the first board and Enable 3 of the second board, and the three low GPIOs (“0”) to the remaining
three enable pins on each board.

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AEK-AUD-C1D9031 - single board AVAS solution

4 AEK-AUD-C1D9031 - single board AVAS solution

The AEK-AUD-C1D9031 is a very compact AVAS solution based on SPC582B60E1 Chorus family MCU and

FDA903D Class D audio amplifiers that emits warning sounds to alert pedestrians of the presence of e-vehicles in

the proximity.

The optimized board size allows installation of more than one AVAS module in an e-car to guarantee that the
warning sound is heard in any direction along the vehicle.

4.1 Hardware overview

Figure 20. AEK-AUD-C1D9031 components

1. SPC582B60E1 automotive microcontroller

2. Class D FDA903D power amplifiers

3. CAN connector

4. Hardware mute switch

5. Turn on/off sound button

6. Connector compatible with AEK-CON-C1D9031

UM2719

UM2719 - Rev 3

The board hosts the SPC582B60E1 automotive microcontroller belonging to the Chorus family, embedding a high
performance e200z2 single core 32-bit CPU with 80 MHz clock, 1088 KB Flash and 96 KB SRAM, in a compact
eTQFP64 package.

The microcontroller monitors and controls the two Class D FDA903D power amplifiers driving the loudspeakers.
The audio transmission from the microcontroller to the two audio amplifiers is implemented via I²S interface
(simulated by an SPI peripheral), while I²C port and GPIOs are used to provide the necessary signals and
communication lines to configure the power amplifiers.

The proposed AVAS solution is designed to be remotely controlled by a central ECU via CAN interface, using the
on-board CAN connector. The board also features a hardware mute button and a button to turn on/off the sound.
A connector is present as well for two sliders: one to manage the speed (engine rpm) and the other to manage
the volume. A compatible version of these sliders is included in the AEK-CON-C1D9031.

page 21/60

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Software overview

4.2 Software overview

The board is ready to be tested. An example of firmware has been already uploaded on it.

If you need to download the firmware into the board again, use SPC5-UDESTK programmer plugged on the JT
connector. The source code is present from AutoDevKit 1.4.0, i.e. a specific demo has been implemented for this
board, “SPC582Bxx_RLA_AEK_AUD_C1D9031 - Avas Compact - Test Application”. To upload the demo into the
microcontroller, refer to Section 7.2.1 How to upload the demos for AEK-AUD-D903V1.

The demo provides an example of how to manage the two FDA903D audio amplifiers with a driver dedicated
to an AEK-AUD-C1D9031 board. The demo shows how to simulate car engine sound, performing diagnostic in
real-time, in two different states: PLAY and MUTE. The detection of the open load in play mode depends on the
sound characteristics (refer to the FDA903D datasheet for details).

To Start and Stop the sound, use the dedicated button shown in Figure 20. While in Stop status, the LED D6
turns on. When the open load fault is detected, LED D8 turns on, while LED D7 is turned on when pushing the
hardware Mute button.

By default, this demo is controlled via CAN by an external MCU/ECU. In addition, it is possible to simulate the
car engine acceleration/deceleration using commands via CAN. The file CANCommunication.h under the source
folder contains the information (SID and Value) related to the messages managed by the demo.

To receive CAN diagnostic messages from the demo, it is mandatory to set the variable

DISTRIBUTED_AVAS_SYSTEM in the main.c as follows:

#define DISTRIBUTED_AVAS_SYSTEM TRUE

The CAN messages will be sent out by the demo to the main ECU in case of open load in play or in mute state.

The sound produced is based on .hex files located under the source/SamplePack folder and have to be loaded
into the Flash memory. A simple Flash memory loading procedure is described in Section 6.2 from step 21 on.
In this demo, we have used a simple algorithm that, depending on the rpm detected, skips some of the wave file
samples to simulate the engine acceleration/deceleration.

Note: It is possible to simulate the car engine acceleration/deceleration and the volume by using two trimmers from

AEK-CON-C1D9031 and changing the ENABLESLIDER variable in the main.c file from

#define ENABLESLIDER FALSE

to

#define ENABLESLIDER TRUE

AG

Important:
Free UDE license allows loading 256 Kb max. To get a full license, you can buy SPC5-UDESTK programmer together with

SPC5-UDEDEBG-TL

unlimited code-size license.

for a one-year, full-feature, unlimited code-size license or SPC5-UDEDEBG for a perpetual, full-feature,

4.3 FCC and IC disclaimer

FCC notice:

This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This
device may not cause harmful interference, and (2) this device must accept any interference received, including
interference that may cause undesired operation. Changes or modifications not expressly approved by the party
responsible for compliance could void the user's authority to operate the equipment. Note: This equipment has
been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules.
These limits are designed to provide reasonable protection against harmful interference when the equipment is
operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy
and if it is not installed and used in accordance with the instruction manual, it may cause harmful interference to
radio communications. Operation of this equipment in a residential area is likely to cause harmful interference, in
which case the user will be required to correct the interference at his own expense.

IC notice:

This Class A digital apparatus complies with Canadian ICES-003. Cet appareil numérique de la classe A est
conforme à la norme NMB-003 du Canada.

,

UM2719 - Rev 3

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5 AVAS system software

The AVAS demo system requires the following set of software tools to develop and load the microcontroller
firmware to drive and monitor the power amplifier:

• SPC5-STUDIO

• STSW-AUTODEVKIT

• AEK-AUD-D903V1 driver

RELATED LINKS

Refer to user manual UM2623 for more information regarding SPC5-STUDIO and STSW-AUTODEVKIT

5.1 SPC5-STUDIO

SPC5-STUDIO is an integrated development environment (IDE) based on Eclipse designed to assist the

development of embedded applications based on SPC5 Power Architecture 32-bit microcontrollers.

The package includes an application wizard to initiate projects with all the relevant components and key elements
required to generate the final application source code. It also contains straightforward software examples for each
MCU peripheral.

Other advantages of SPC5-STUDIO include:

•

ability to integrate other software products from the standard Eclipse marketplace

• free license GCC GNU C Compiler component

• support for industry-standard compilers

• support for multi-core microcontrollers

• PinMap editor to facilitate MCU pin configuration

and SPC5-UDESTK-SW debugger

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AVAS system software

RELATED LINKS

Download the SPC5-UDESTK-SW software to run and debug applications created with SPC5-STUDIO

5.2 STSW-AUTODEVKIT

The STSW

The main advantages of STSW-AUTODEVKIT are:

• integrated hardware and software components, component compatibility checking and MCU and peripheral

• allows creation of new system solutions from existing solutions by adding or removing compatible function

• Hardware abstraction means new code can be generated immediately for any compatible MCU

• High-level application APIs to control the AEK-AUD-D903V1 board.

The GUI helps configure interfaces, including I²C and I²S, and can automatically manage all relevant pin
allocation and deallocation operations.

-AUTODEVKIT plug-in for Eclipse extends SPC5-STUDIO for automotive applications.

configuration tools

boards

5.3 AEK-AUD-D903V1.c and sound.c drivers

The AEK-AUD-D903V1.c driver and sound.c library are provided with the STSW
facilitate the programming phase.

5.3.1 AEK-AUD-D903V1.c driver

This driver contains the functions to configure the IB and DB registers of the FDA903D audio amplifier for
appropriate system management and control.

Consider the IB8 register below

.

-AUTODEVKIT installation to

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AEK-AUD-D903V1.c and sound.c drivers

Table 8. FDA903D IB8 register description

UM2719

Data bit Default value

D7-D6 11

D5 0

D4 0

D3-D1 000

D0 0

Definition

Bit value Effect

Current Sensing Full scale setting:

0

1

10

11

0 Channel in TRISTATE (PWM OFF)

1 Channel with PWM ON

0 Channel DC Diag disable

1 Channel DC Diag start

000 High impedance configuration

001 Reserved

010 Reserved

011 Output: Current sensing enable

100 Reserved

101 Output: PWM synchronization signal

110 Reserved

111 Reserved

0 Channel in MUTE

1 Channel in PLAY

1 A I

2 A I

4 A I

8 A I

max

max

max

max

I²S test pin configuration

To put the amplifier in PLAY mode, we need to configure the register accordingly:

turn on the PWM setting IB8[D5] = 1

•

• put the channel in play setting IB8[D0] = 1

The Initial state is the default 11000000. To reach the state PWM on state, we compute 11000000 OR 00100000
to obtain 11100000. To reach the PLAY mode state, we perform 11100000 OR 0001000 to obtain 11110000.

It takes several operations to modify the relevant bits in the IB register in order to transmit a simple instruction to
the amplifier.

The AEK-AUD-D903V1.c simplifies these operations through a list of APIs that can configure the IB registers in a
single command.

For example, the AEK_903D_Play(AEK_AUD_D903V0) function configures the IB8 register bits required to set
the amplifier in PLAY mode.

Note: The parameter of the function indicates the name of the amplifier to control, so in a stereo system with two audio

boards, we must distinguish between AEK-AUD-D903V0 and AEK-AUD-D903V1.

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AEK-AUD-D903V1.c and sound.c drivers

Figure 21. API AEK_903D_Play(AEK_AUD_D903V0)

1. The function saves the current state of the IB8 register to the variable FDA903D_Status_IB

2. The function changes the value of variable FDA903D_Status_IB to turn on PWM and activate PLAY mode.

3. The function writes the value of the

PLAY mode.

FDA903D_Status_IB variable to the IB8 register, effectively setting the amplifier in

1

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2

3

Some APIs in the AEK-AUD-D903V1.c driver require specific configuration parameters. In the following example,
bits D3, D2 and D1 combine to define different configurations (000 = high impedance configuration, 011 = current
sensing configuration, etc.). This API therefore requires indication of the desired configuration as well as the
relevant device when it is invoked.

Figure 22. I2S Test Pin configuration API

1. The user must replace the description with the appropriate value field to indicate the desired configuration.

1

UM2719 - Rev 3

The following table shows all the available functions divided according to the register on which they act.

page 25/60

Table 9. list of API functions in AEK-AUD-D903V1.c

Register API

AEK_903D_EnableWritingOnlBs

AEK_903D_DisableWritingOnlBs

IB0

IB1

IB2

IB3

IB4

IB5

AEK_903D_SetlnputDataFormats

AEK_903D_SelectChannelPosition

AEK_903D_SetVoltageMode

AEK_903D_SetI2SWordSelect

AEK_903D_SetPWMSwitchingFrequency

AEK_903D_SetPwmAplifierDithered

AEK_903D_SetPwmAplifierNotDithered

AEK_903D_SetPwmlnPhase

AEK_903D_SetPwmOutOfPhase

AEK_903D_SetDiagShort2SupplyTiming

AEK_903D_DisableLowRadiationFunction

AEK_903D_EnableLowRadiationFunction

AEK_903D_ConfigurePowerLimit

AEK_903D_DisableOutputVoltageOffsetDetector

AEK_903D_EnableOutputVoltageOffsetDetector

AEK_903D_DisablelnputOffsetDetector

AEK_903D_EnablelnputOffsetDetector

AEK_903D_DisableOutputOffsetCurrentDetector

AEK_903D_TriggerOutputOffsetCurrentDetector

AEK_903D_DisableHighPasslnDAC

AEK_903D_EnableHighPasslnDAC

AEK_903D_DisableNoiseGating

AEK_903D_EnableNoiseGating

AEK_903D_DisableOpenLoadlnPlayDetection

AEK_903D_TriggerOpenLoadlnPlayDetection

AEK_903D_EnableOutputVoltageOffsetInfoOnCDDIAG

AEK_903D_DisableOutputVoltageOffsetlnfoOnCDDIAG

AEK_903D_ConfigureThermalWarninglnfoOnCDDIAG

AEK_903D_EnableOvercurrentlnfoOnCDDIAG

AEK_903D_DisableOvercurrentlnfoOnCDDIAG

AEK_903D_EnablelnputOffsetlnfoOnCDDIAG

AEK_903D_DisablelnputOffsetlnfoOnCDDIAG

AEK_903D_EnableShortToVccOrGndlnfoOnCDDIAG

AEK_903D_DisableShortToVccOrGndlnfoOnCDDIAG

AEK_903D_EnableHighVoltageMutelnfoOnCDDIAG

AEK_903D_DisableHighVoltageMutelnfoOnCDDIAG

AEK_903D_EnableUvlovcclnfoOnCDDIAG

AEK_903D_DisableUvlovcclnfoOnCDDIAG

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AEK-AUD-D903V1.c and sound.c drivers

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Register API

AEK_903D_EnableThermalShutdownlnfoOnCDDIAG

IB5

IB6

IB7

IB8

IB9

IB10

IB11

IB12 AEK_903D_SetThermalWarning

IB13

IB14

AEK_903D_DisableThermalShutdownlnfoOnCDDIAG

AEK_903D_EnablePwmPulseSkippinglnfoOnCDDIAG

AEK_903D_DisablePwmPulseSkippinglnfoOnCDDIAG

AEK_903D_SelectMuteTimingsetup

AEK_903D_SelectAudioSignalGainControl

AEK_903D_SelectGainSetting

AEK_903D_SelectDiagnosticRampTime

AEK_903D_SelectDiagnosticHoldTime

AEK_903D_SelectCurrentSensingCommunication

AEK_903D_SelectCurrentSensingProtocolConfiguration

AEK_903D_SetCurrentSensingFullScale

AEK_903D_SetChannelWithPWMoff

AEK_903D_SetChannelWithPWMon

AEK_903D_Eco_Mode

AEK_903D_StartDCDiag

AEK_903D_DisableDCDiag

AEK_903D_I2TestPinConfiguration

AEK_903D_Play

AEK_903D_Mute

AEK_903D_EnableWatchDogForWordSelect

AEK_903D_DisableWatchDogForWordSelect

AEK_903D_SetShortLoadlmpedanceThreshold

AEK_903D_SetOpenLoadlmpedanceThreshold

AEK_903D_SetCurrentOffsetThreshold

AEK_903D_SelectOverCurrentProtectionLevel

AEK_903D_SetSlowSlopePWMConfiguration

AEK_903D_SetDefaultPWMConfiguration

AEK_903D_EnableDigitalMutelnPlayForTW1

AEK_903D_DisableDigitalMutelnPlayForTW1

AEK_903D_SetFeedbackOnLCFilter

AEK_903D_SetFeedbackOnOutPin

AEK_903D_SetupLCFilter

AEK_903D_Enable903ToBeProgramVial2C

AEK_9030_Disable903ToBeProgramVial2C

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AEK-AUD-D903V1.c and sound.c drivers

Other functions in AEK-AUD-D903V1.c that are not register specific are listed below:

AEK_903D_Write_IB: I²C write to IB registers

AEK_903D_Read_IB: I²C read of single IB register

AEK_903D_Read_All_IB: I²C read of all IB registers

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AEK-AUD-D903V1.c and sound.c drivers

AEK_903D_Read_DB: I²C read of single DB register

AEK_903D_Read_All_DB: I²C read of all DB registers

AEK_903D_SetDefaultRegi
sters:

AEK_903D_SetEnables: used inside the AEK_903D_Init function to set/clear the Enable pins of the board as defined in

AEK_903D_Init: initializes the I²C and I²S protocol and to launch the AEK_903D_SetEnables function

AEK_903D_I2C_Init: initializes the I²C peripheral

AEK_903D_I2S_Init: initializes the I²S peripheral

AEK_903D_CheckOpenLoa
dInPlayDetection:

initializes I²C registers in AEK-AUD-D903V1 and sets first bit of IB14 to 1 (ready to work)

the configuration

returns the result of the Open Load in Play Detection test on the DB0 register in the
FDA903D_Errors structure

AEK_903D_CheckOffsetCu
rrent:

AEK_903D_CheckInputOffs
etDetector:

AEK_903D_CheckOutputVo
ltageOffsetDetector:

AEK_903D_CheckDCDiagn

returns the result of the Current Offset detection test on the DB0 register in the
FDA903D_Errors structure

returns the result of the Input Offset Detection test on the DB0 register in the
FDA903D_Errors structure

returns the result of the Output Voltage Offset Detection test on the DB0 register in the
FDA903D_Errors structure

returns the result of the DC Diagnostic on the DB1 register in the FDA903D_Errors structure

ostic:

AEK_903D_Diagnostic: reads the DB register and signals whether a certain failure condition has occurred

(SHOR

T2VCC, SHORT2GND, OVERCURRENT, UNDERVOLTAGE, OVERTEMPERATURE

OVERVOLTAGE) in the FDA903D_Errors structure

5.3.2 sound.c description

This library contains APIs for the generation, reproduction and simulation of audio wave signals.

initWaveFile: This function takes as input the start address of the first WAV file and the number of files

that you intend to load into memory (maximum number dim=10) and initializes the sound_db
structure with all the necessary addresses to identify the beginning and end of each W

getStartWavFile: This function computes the address that points to the first audio sample of a given WAV file.

Y

ou must provide the function with an integer that identifies the location of the WAV file within

the sound_db structure previously initialized by the initWaveFile function.

getHalfWavFile: This function computes the address that points to the middle audio sample of a given WAV file.

ou must provide this function with an integer that identifies the location of the WAV file within

Y
the sound_db structure previously initialized by the initWaveFile function.

AV file.

GetEndWavFile: This function computes the address that points to the last audio sample of a given WAV file.

ou must provide this function with an integer that identifies the location of the WAV file within

Y
the sound_db structure previously initialized by the initWaveFile function.

swapEndian32: This function swaps the order of the bits: from little (big) endian to big (little) endian.

validate_wav_file: This function validates the WAV file by checking the WAV file descriptor parameters.

checkWavFile: This function checks the WAV file and identifies the start, middle and end of each WAV file,

removing the W

AV file header.

load_channel_data: This function loads new data to the transmission buffer.

playSound: This function plays the sample provided in MONO mode by taking as input a pointer to function

that generates the audio samples and an integer indicating the volume.

playSoundStereo: This function plays the sample provided in STEREO mode by taking as input a pointer to

function that generates the audio samples and an integer indicating the volume.

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AEK-AUD-D903V1.c and sound.c drivers

The last two functions deal with actual sound reproduction. Since these two functions work in the same way, with
the only difference being that one plays mono WAV files and the other stereo files, we will describe how the first
one works.

Figure 23. playSound API

1. This input is a function pointer to the sample that playSound will run. The pointer must refer to the user function, which must

return a

2. In this MONO mode example, the same sample is transmitted to both channels. In STEREO mode, the samples for the left

and right channels may differ.

uint32_t data type that is assigned to the variable to be transmitted.

1

2

The sound.c library allows storing samples generated by mathematical functions or writing a function able to
take audio samples from any file WAV loaded in memory.

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6 How to play an audio WAV file

6.1 SPC582B60E1 memory map

Excluding the 64 KB data flash, the remaining 1024 KB MCU memory is divided into the following blocks:

•

4 blocks of 16 KB (Low Flash Blocks)

• 2 blocks of 32 KB (Low Flash Blocks)

• 2 blocks of 64 KB (Mid Flash Blocks)

• 6 blocks of 128 KB (Large Flash Blocks)

We allocate the Low and Mid Flash Blocks to load and execute the source code of our application, and the
remaining 6 Large Flash Blocks for the WAV audio files. This of course means that the WAV files cannot exceed
768 KB.

The following microcontroller Flash memory map shows the physical addresses used to identify and divide the
different memory portions.

Table 10. Flash memory map of SPC582B

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How to play an audio WAV file

Start address End address Description

Data Flash: 64 KB

0x00804000 0x00807FFF 16 KB EEPR0M block1 1

0x00808000 0x0080BFFF 16 KB EEPR0M block2 1

0x0080C000 0x0080FFFF 16 KB EEPR0M block3 1

0x00810000 0x00FBFFFF Reserved

Low & Mid Flash blocks: 256 KB for application code

0x00FC0000 0x00FC3FFF 16 KB Code Flash block1 0

0x00FC4000 0x00FC7FFF 16 KB Code Flash block2 0

0x00FC8000 0x00FCBFFF 16 KB Code Flash block3 0

0x00FCC000 0x00FCFFFF 16 KB Code Flash block4 0

0x00FD0000 0x00FD7FFF 32 KB Code Flash block0 0

0x00FD8000 0x00FDFFFF 32 KB Code Flash block1 0

0x00F E0000 0x00FEFFFF 64 KB Code Flash block0 0

0x00FF0000 0x00FFFFFF 64 KB Code Flash block1 0

Large Flash Blocks: 768 KB for audio WAV files

0x01000000 0x101FFFF 128 KB Code Flash block0 0

0x01020000 0x103FFFF 128 KB Code Flash block1 0

0x01040000 0x0105FFFF 128 KB Code Flash block2 0

0x01060000 0x0107FFFF 128 KB Code Flash block3 0

0x01080000 0x0109FFFF 128 KB Code Flash block4 0

0x010A0000 0x010BFFFF 128 KB Code Flash block5 0

0x010C0000 0x0FFFFFFF Reserved

1 RWR partition

RWW Partition ID

6.2 Uploading audio WAV file

Use the procedure below to upload audio WAV files.

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Uploading audio WAV file

Step 1. Launch SPC5-STUDIO and Create a new SPC5-STUDIO application for Chorus 1M (SPC582B).

Step 2. Right-click the [source] folder to create another folder inside it.

ou can name the folder “audio files”.

Y

Step 3. Copy the desired WAV files and paste them inside the newly created folder.

Verify that all files have been inserted.

Figure 24. Project folder for audio files

Step 4. Compile your application.

This creates a file named application.ld in your project folder

.

Step 5. In the same folder, make a copy of the application.ld file and rename the file according to the

compiler you are using.

– Free GCC → user_freegcc.ld.

– Green Hills → user_ghs.ld.

– Hitech → user_hightec.ld.

Step 6. Double click on the user_freegcc.ld file to open it.

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Uploading audio WAV file

Step 7. Inside the file, modify the memory partition by splitting the flash block into flash and sound blocks.

– The new flash block is 256 KB where application source code is loaded and executed

– The new sound block is 768 KB where audio WAV files are saved

Figure 25. Old flash block memory allocation

1. Old 1 MB flash block

1

1. New 256 KB flash block

2. New 768 KB sound block

Figure 26. New flash block memory allocation

1

2

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Step 8. Define a section called sounddb as indicated below.

Figure 27. sounddb definition

1. Location of new sounddb definition

2. sounddb definition code

1

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Uploading audio WAV file

2

Step 9. Right-click the [source] folder to create a new file called sounddb.s.

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Uploading audio WAV file

Step 10. In the file, indicate the path of the WAV files to be loaded and declare the variables that identify the

physical start and end addresses of the various WAV files.

Below is an example with paths and address variables for six WAV files.

Figure 28. sounddb.s audio file declarations

1. first line of code

2. start address variable for first audio file

3. end address variable for first audio file

4. path to first audio file

1

2

3

4

UM2719 - Rev 3

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Step 11. Recompile the project.

The size of the build output should now include the audio files added in the sounddb.s file.

After compiling, the [build] folder will contain the output file of the application in BIN, DMP, ELF, HEX,
MAP and MOT formats.

Figure 29. Build output before adding sounddb.s component

1. size of build output before adding sounddb.s component

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Uploading audio WAV file

1

Figure 30. Build output after adding sounddb.s component

1. added sounddb.s component

2. size of build output after adding sounddb.s component

1

2

UM2719 - Rev 3

Step 12. Expand the [build] folder, select the out.hex file and move or copy it to the same folder where the

audio files were saved.

The .hex file can actually be saved to any external folder.

page 35/60

Step 13. Rename the .hex file as you prefer.

This file contains all the application files.

Step 14. Open your .hex file using a text editor.

You can use the SPC5-STUDIO editor or an external one.

Figure 31. Open hex file with editor

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Step 15. Examine the file and verify that the address is 0200000400FCFE.

00FC is the base address (the first 16 bits) of the physical address of the data contained in each
record.

Figure 32. hex file data

Legend:

: start code,

end of file, 04 Extended linear address for 32-bit addressing, etc.),

number of bytes in data field , address of data added to base address, record type (00 data, 01

data 32 hex digits, checksum

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Step 16. In the text editor, search for the string following: 020000040100.

This string contains the base address of the sound partition in the memory where the audio WAV
samples specified in sounddb.s are loaded. The sound partition was defined previously in the
user_freegcc.ld file.

Figure 33. Starting point of audio content in hex file

1. search string to find

2. string found in hex file

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Uploading audio WAV file

1

2

Step 17. Delete all the lines in the hex file before the starting line of the audio content.

The hex file now only contains the sample audio data to be played by the AVAS system.

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Uploading audio WAV file

Step 18. Open the soundb.s file and remove or comment out all paths to the audio sample files.

This ensures that the application does not include the audio content the next time you compile, leaving
only the information regarding the source code.

Figure 34. sounddb.s file with audio sample file paths removed

1. path statements to be commented or deleted

2. build file returns to its original size when the audio content is removed

1

1

1

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1

1

1

2

Step 19. Recompile the project.

Step 20. Connect the mini-B USB port on the Discovery AEK-MCU-C1MLIT1 control board to a USB port on

your PC with an appropriate mini USB to USB cable.

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Step 21. Launch SPC5-UDESTK-SW on your PC and run the debug.wsx file.

This opens a [Multicore / multi program loader] window.

Figure 35. SPC5-UDESTK-SW software with loader window

1. loader window

2. browse file icon

3. remove file icon

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Uploading audio WAV file

213

Step 22. Click on the [delete] icon in the menu bar to remove the current file from the [Load File To].

Step 23. Click on the [browse] icon to add a new file.

Step 24. Browse to you hex file and select [open].

The [Multicore / multi program loader] window reopens with the hex file in the [Load File To] list.

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Step 25. Click [OK] to open the [FLASH/OTP Memory Programming Tool] window.

Note: The free UDE license allows you to upload a maximum file size of up to 256 KB.

Figure 36. FLASH/OTP Memory Programming Tool

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Uploading audio WAV file

Step 26. Select the [Erase] button.

A Flash selection window appears.

Step 27. Select from memory block 8 (0x01000000) to block13 and click [Start].

Figure 37. UDE Flash erase tool

1. blocks to be erased

2. start erase procedure

3. exit when erase has completed

2

1

Step 28. Click [Exit] when the process has finished.

3

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Step 29. In the FLASH/OTP Memory Programming Tool, click on [Program All].

This process loads the audio samples.

Step 30. Wait until the operation has completed and select [Exit].

Step 31. Close UDE-STK.

You have loaded your audio samples into the designated memory portion.

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Uploading audio WAV file

Step 32. Save your SPC5-STUDIO application and keep the user.ld and sounddb.s files in a folder

These two files are important because they are the starting point for the creation of the AEK-AUD­D903V1 application.

.

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7 AEK-AUD-D903V1 sample applications

7.1 How to create a simple AEK-AUD-D903V1 application

Before you start, ensure that the audio samples have been correctly loaded in the microcontroller memory.

This procedure shows you how to play an audio WAV file loaded in memory and perform some diagnostics.

Step 1. Create a new SPC5-STUDIO application for the SPC582B series microcontroller and add the following

components:

– SPC582Bxx Init Package Component RLA

– SPC582Bxx Low Level Drivers Component RLA

These components must be added immediately, or the remaining will not be visible.

Step 2. Add the following further components:

– AutoDevKit Init Package Component

– SPC582Bxx Platform Component RLA

– AEK-AUD-D903V1 Component RLA

Figure 38. SPC5-STUDIO adding audio project components

1. SPC582Bxx Platform Component RLA

2. Open available components

3. AEK-AUD-D903V1 Component RLA

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AEK-AUD-D903V1 sample applications

2

1

3

Step 3. Select [AEK-AUD-D903V1 Component RLA] to open the [Application Configuration] window.

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How to create a simple AEK-AUD-D903V1 application

Step 4. Select the I2S (DSPI) port and the I2S WS. Then, click on [+] to add a new element to the AEK AUD

D903V1 list.

If you want to create a STEREO version, you will need to insert a second element in the list.

Figure 39. AEK-AUD-D903V1 component configuration

1. AEK-AUD-D903V1 component

2. Pin association

3. add new element icon

4. new entry

1

2

4

Step 5. Double click on the newly added element to configure the I²C interface.

The I²C configuration window opens.

3

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How to create a simple AEK-AUD-D903V1 application

Step 6. Select the I²C HW and the address for the power amplifier derived from a combination of enable pins.

To create a STEREO version, you need to assign two different addresses for the two elements so that
you can communicate with each power amplifier independently.

Figure 40. AEK-AUD-D903V1 I²C configuration

1. I2C HW selection

2. Enable pin configuration

3. Confirm configuration

3

1

2

Step 7. Click the [Allocation] button below the AEK-AUD-D903V1 list and click [OK] in the confirmation

window.

This operation delegates automatic pin allocation to STSW-AUTODEVKIT. If the system warns you that
the selected I²S (DSPI) port is not available, restart from step 3 and select another I²S port or another
I²S WS.

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How to create a simple AEK-AUD-D903V1 application

Step 8. Click on the PinMap editor icon to check that the twelve required pins have been allocated

appropriately.

– I2S SCL (pin 24 → PG11)

– I2S SDA1 (pin 48 → PD5)

– I2S WS (pin 29 → PB11)

– I2S CR (pin 26 → PD11), not used in this application

– I²C SCL (pin 32 → PB8)

– I²C SDA (pin 31 → PB9)

– 4 GPIO pins for Enable

– 1 GPIO pin for Hardware Mute

– 1 GPIO pin for CDDIAG, not used in this application

Figure 41. PinMap editor

1. PinMap editor icon

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Step 9. Close the PinMap Editor and save the application.

Step 10. Generate and build the application using the appropriate icons in SPC5-STUDIO.

The project folder will be populated with new files, including main.c and the components folder with
AEK-AUD-D903V1 and sound drivers.

Step 11. Before starting coding, insert the user_freegcc.ld and sounddb.s files prepared previously.

1

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How to create a simple AEK-AUD-D903V1 application

Step 12. Open the main.c file and include AEK-AUD-D903V1 and sound files, and define the required

constants and variables.

#include "components.h"
#include "sound.h"
#include "AEK-AUD-D903V1.h"

/*************** variables section ***************/

extern uint32_t* engine_start1;

/* These variables are defined in the file sounddb.s,
thus it is necessary to declare them as extern */

int16_t* wavfileBeginPtr; //pointer to wave file initial point
int16_t* wavfileEndPtr; //pointer to wave file final point
int16_t* wavfilePtr; //pointer to wave file current position
uint32_t volume = 1;

/* This variable is defined for the Playsound function.
There is a volume threshold under which the Open Load in Play Detection Test is not
valid.
Thus, if you perform this Test, make sure to increase the volume until you overcome
this threshold */
/************* end variables section *************/

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Step 13. Place the following functions inside main():

int main(void)

{
componentsInit();

/* This function initializes all the imported components. It is present in the
generated file. */

irqIsrEnable(); /* This function deals with interrupt management */
initWaveFile(&engine_start1, 6);

/*This function takes in input the starting address of the first WAVE file and the
number of files yow want to upload */

AEK_903D_Init(AEK_AUD_D903V1_DEV0);

/* This function initializes the I²C and I2S peripherals and sets the enable pins
chosen during the configuration.
In the STEREO case, you would need to duplicate this function for the second device
called AEK_AUD_D903V1_DEV1. */

AEK_903D_SetDefaultRegisters(AEK_AUD_D903V1_DEV0);

/* This function sets the register to the default state. In the STEREO case,
you would need to duplicate this function for the second device called
AEK_AUD_D903V1_DEV1.

AEK_903D_SelectOverCurrentProtectionLevel(AEK_AUD_D903V1_DEV0,
IB11_OVER_CURRENT_PROTECTION_4A);

/* This function selects the current protection level from four possible values:
4A, 6A, 8A, and 11A.
The protection circuit will trigger as soon as the chosen threshold is exceeded.
Increasing the volume, you could end up triggering the current protection circuit.
Clearly, lower the threshold (4A), higher the protection triggering probability.
In the STEREO case, you would need to duplicate this function for the second device
called AEK-AUD-D903V1_DEV1. */

AEK_903D_Play(AEK_AUD_D903V1_DEV0);

/*This function turns on the PWM and puts in PLAY state the amplifier.
In the STEREO case, you would need to duplicate this function for the second device
called AEK_AUD_D903V1_DEV1. */

wavfilePtr = wavfileBeginPtr = getStartWavFile(0); // set the start address of the

first wave file

wavfileEndPtr = getEndWavFile(0); // set the end address of the first wave file/*

Application main infinite loop. */for ( ; ; )

{
playSound(volume, userFunction);

/* This function allows to play the samples generated with the function pointed by
‘userFunction’.
In the STEREO case, you would need to use the playSoundStereo().*/

AEK_903D_Diagnostic(AEK_AUD_D903V1_DEV0);

/* This function updates the FDA903_Errors structure with the information contained
in the DB registers.
In the STEREO case, you would need to duplicate this function for the second device
called AEK_AUD_D903V1_DEV1. */

AEK_903D_TriggerOpenLoadInPlayDetection(AEK_AUD_D903V1_DEV0);

/* This function triggers the Open Load in Play Detection.
In the STEREO case, you would need to duplicate this function for the second device
called AEK_AUD_D903V1_DEV1. */

AEK_903D_CheckOpenLoadInPlayDetection(AEK_AUD_D903V1_DEV0);

/* This function updates the FDA903_Errors structure with the information inside
the DB1 register.
In the STEREO case, you would need to duplicate this function for the second device
called AEK_AUD_D903V1_DEV1. */

}
}

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How to create a simple AEK-AUD-D903V1 application

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Available demos for AEK-AUD-D903V1

Step 14. Declare the function uint32_t userFunction(void); in the header file.

ou can now write the following code between the variables section and the main() function.

Y

/* In case of multiple wave files, these variables will be re-assigned with new
addresses using the same above functions with different parameters, e.g.
getStartWavFile(1); */

uint32_t userFunction()
{
uint16_t sampleWav; // sample from wave file to be processed
int32_t sampleToPlay = 0;
if(wavfilePtr > wavfileEndPtr)

// if we reach the end of the file we restart from the initial address

{
wavfilePtr = wavfileBeginPtr;
}
sampleWav = ( *wavfilePtr << 8) | ((*wavfilePtr >> 8) & 0xFF);

// swap endianness

sampleToPlay = (int32_t)sampleWav;

// place the sample in a 32-bit format

wavfilePtr++;

//pointer to the next wave file sample

return sampleToPlay;

}

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Step 15. Save, generate and compile the application.

Step 16. Open the BoardV

iew Editor provided by STSW-AUTODEVKIT.

Step 17. This provides a graphical point-to-point guide on how to wire the boards.

Step 18. Connect the AEK-MCU-C1MLIT1 to a USB port on your PC using a mini-USB to USB cable.

Step 19. Launch SPC5-UDESTK-SW and open the debug.wsx file in the AEK_AUD_D903V1 – Application /

UDE folder.

Step 20. Run and debug your code.

7.2 Available demos for AEK-AUD-D903V1

There are eight different demos with specific features provided with the audio component:

SPC582Bxx_RLA AEK-AUD-D903V1 - Test Application

1.

2. SPC582Bxx_RLA AEK-AUD-D903V1 - Mono audio and Diagnostic - Test Application

3. SPC582Bxx_RLA AEK-AUD-D903V1 - Stereo audio and Diagnostic - Test Application

4. SPC582Bxx_RLA AEK-AUD-D903V1 - I²C Software Mono audio - Test Application

5. SPC582Bxx_RLA AEK-AUD-D903V1 - Engine Sound Simulator Test Application

6. SPC58ECxx_RLA AEK-AUD-D903V1 - I²C Software Mono audio - Test Application for SPC58EC-DISP

7. SPC58ECxx_RLA AEK-AUD-D903V1 - Mono audio - Test Application for SPC58EC-DISP

8. SPC584Bxx_RLA AEK-AUD-D903V1 - Mono audio - Test Application for SPC584B-DIS

Note: More demos may become available with new AutoDevKit releases.

7.2.1 How to upload the demos for AEK-AUD-D903V1

Follow the procedure below to import the demos into SPC5-STUDIO.

Step 1. Select [Import samples from application library] from the Common tasks pane.

An Import application Wizard appears.

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Available demos for AEK-AUD-D903V1

Step 2. In the Import application Wizard, insert the appropriate product family details.

Figure 42. SPC5-STUDIO Import application Wizard

1. Import samples task button

2. Product family selection panel

2

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Step 3. Select the desired application from the library.

1

2

Figure 43. SPC5-STUDIO application library

1. application selector

2. confirmation buttons

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Available demos for AEK-AUD-D903V1

7.2.2 Mono audio – Test Application (SPC584Bxx and SPC58ECxx)

This demo plays an audio wave file stored in memory.

The main APIs in this demo are:

• AEK_903D_Init: initializes the I²C and I2S interface

• initWaveFile: initializes the structure that contains the addresses used to identify the beginning and end
of each wave file

• getStartWavFile: computes the address pointing to the first audio sample of a given wave file

• GetEndWavFile: computes the address pointing to the last audio sample of a given WAV file

• playSound: plays the samples provided through a pointer to function able to generate audio samples

7.2.3 I²C Software Mono audio – Test Application (SPC582Bxx and SPC58ECxx)

This demo is like the Mono audio – Test Application, but the I²C protocol is implemented via software thanks to
the allocation of two GPIO pins suitably configured by AutoDevKit itself.

7.2.4 Mono audio and Diagnostic - Test Application (SPC582Bxx)

This demo shows how to reproduce an audio wave file and how to perform system diagnostics during the PLAY
and MUTE states, using the button on the microcontroller board to switch between the two states. The audio
reproduction functions are the same as those in the Mono audio - Test Application, so the functions described
below relate to diagnostics only.

• AEK_903D_TriggerOpenLoadInPlayDetection: triggers the Open Load in Play Detection test

• AEK_903D_CheckOpenLoadInPlayDetection: verifies the result of the Open Load in Play Detection test

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• AEK_903D_CheckOffsetCurrent: verifies the result of the Output Current Offset Detection test

• AEK_903D_CheckOutputVoltageOffsetDetector: verifies the result of the Output Voltage Offset
Detection test

• AEK_903D_CheckInputOffsetDetector: verifies the result of the Input Offset Detection test

• AEK_903D_Diagnostic: reads the DB register and reports if a failure condition has
occurred (SHORT2VCC, SHORT2GND, OVERCURRENT, UNDERVOLTAGE, OVERTEMPERATURE
OVERVOLTAGE)

• AEK_903D_Mute: changes from PLAY to MUTE state

• AEK_903D_StartDCDiag: changes from MUTE to DC Diag state and to perform the DC diagnostic

• AEK_903D_CheckDCDiagnostic: verifies the result of the DC diagnostic.

The red LED on the Discovery control board provides load (speaker) connection status resulting from the Open
Load in Play Detection test during PLAY state operation and the DC diagnostic in MUTE:

• The red LED goes on when an open load fault is detected, and the tests performed are self-validated.

• The red LED stays off when the load is correctly connected, or the tests cannot be self-validated.

7.2.5 Stereo audio and Diagnostic - Test Application (SPC582Bxx)

This demo is the stereo version of the Mono audio and Diagnostic application, in which the functions used are
duplicated to perform the same diagnostics on both boards (i.e., audio channels).

• The red LED communicate the load status of the first board

• The yellow LED communicates the load status of the second board.

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Available demos for AEK-AUD-D903V1

7.2.6 Engine Sound Simulator - Test Application for AVAS purpose (SPC582Bxx)

The demo offers an entry-level AVAS implementation using the AEK-AUD-D903V1 AutoDevKit component. The
application uses an algorithm to simulate the sound of an internal combustion engine during acceleration and
deceleration.

The application allows you to:

1. reproduce a WAV file for a car engine sound recorded in Neutral

2. simulate engine ignition and shutdown sounds through a user button on the control board

3. simulate engine noise during acceleration and deceleration

4. change the volume and rpm values through two potentiometers

The acceleration and deceleration phases are simulated by increasing and decreasing the number of samples
reproduced. For example, consider that for an engine idling in Neutral at 800rpm, its sound may be represented
by a sinusoidal wave with period T. We simulate the acceleration phase by decreasing the period (increasing
signal frequency), as shown in the following figure.

Figure 44. Audio sample frequency modulation

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Available demos for AEK-AUD-D903V1

The samples in the MCU memory are sampled at 44,100 Hz frequency, and frequency modulation is simulated by
varying the number of samples to be played. The following image shows the algorithm operating principle.

Figure 45. Varying sample numbers to simulate frequency modulation

The userFunction() used in this application has the following characteristics:

1. As soon as the application is started and the ignition command is given, the initial pointer is assigned to the
first sample to be played, while the final address is assigned to the last sample.

2. At the end of the first cycle (i.e., when the pointer to the current sample is the same as the pointer of the last
sample in the audio file for the first time), the algorithm no longer restarts from the first sample, but 90,000
samples after the first. This effectively simulates the effect of engine start and engine idle with a few seconds
of recording.

uint32_t userFunction()
{
if(acc_first_time)
{
wavfilePtr = wavfileBeginPtr = getStartWavFile(0);
wavfileEndPtr = getEndWavFile(0);
acc_first_time = false;
}
if(wavfilePtr > wavfileEndPtr)
wavfilePtr = wavfileBeginPtr + 90000;
int32_t amplitude = 0;
uint16_t sampleWav;
sampleWav = ( *wavfilePtr << 8) | ((*wavfilePtr >> 8) & 0xFF);
//raw sample, change endianness
amplitude = (int32_t)sampleWav;

The acceleration and deceleration is obtained through voltage variation from a potentiometer. This external input
is converted by the microcontroller SARADC, and its value is stored in an rpm variable. The higher the value of
rpm, the greater the number of samples to be skipped.

This method, shown in the code snippet below, can therefore simulate variations in engine rpm sounds in
acceleration and deceleration.

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if (rpm1 <= 2200)

{
if (rpm1 == 900)
{
if (j < 23)
wavfilePtr++;
else
{
wavfilePtr+ = 2;
j = 0;
}
}
else if (rpm1 == 1000)
{
if (j < 20)
wavfilePtr++
else
{
wavfilePtr+ = 2;
j = 0;
}
}
etc...
…
…
…

else if (rpm1 == 2200)

{
if (j < 12)
{
wavfilePtr++;
}
else
{
wavfilePtr =+ 4;
j = 0;
}
}
else//800 rpm
wavfilePtr++;

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Available demos for AEK-AUD-D903V1

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Revision history

Date Version Changes

19-May-2020 1 Initial release.

17-Feb-2021 2

15-Apr-2021 3

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T

able 11. Document revision history

Added Section 4 AEK-AUD-C1D9031 - single board AVAS solution, Section 4.1 Hardware overview,
Section 4.2 Software overview and Section 4.3 FCC and IC disclaimer

Updated Section 1 A

automotive power amplifier, Section 3.2 FDA903D I²S protocol Section 3.3 FDA903D I²C protocol,
Section 3.3.1 I²C protocol writing procedure and Section 3.6 Stereo mode.

VAS system hardware, Section 3 AEK-AUD-D903V1 evaluation board for

.

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Contents

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Contents

1 A

VAS system hardware ............................................................2

2 AEK-MCU-C1MLIT1 Discovery board audio support ................................3

2.1 I²S bus interface on the SPC582B60E1 microcontroller...............................4

2.1.1 I²S protocol details .......................................................4

2.1.2 I²S emulation on DSPI for SPC5 MCU control of FDA903D amplifier .................4

2.2 I²C bus interface on the SPC582B60E1 microcontroller ..............................6

3 AEK-AUD-D903V1 evaluation board for automotive power amplifier ................8

3.1 FDA903D finite state machine ....................................................8

3.1.1 FDA903D FSM state descriptions ...........................................10

3.2 FDA903D I²S protocol..........................................................10

3.3 FDA903D I²C protocol .........................................................11

3.3.1 I²C protocol writing procedure ..............................................12

3.3.2 I²C protocol: reading procedure.............................................14

3.3.3 IB registers in I²C .......................................................15

3.3.4 DB registers in I²C.......................................................16

3.3.5 Driver ................................................................17

3.4 Potentiometers ...............................................................17

3.5 Successive approximation analog-to-digital converter (SARADC) .....................18

3.6 Stereo mode .................................................................18

4 AEK-AUD-C1D9031 - single board AVAS solution..................................21

4.1 Hardware overview ............................................................21

4.2 Software overview.............................................................22

4.3 FCC and IC disclaimer .........................................................22

5 AVAS system software............................................................23

5.1 SPC5-STUDIO ...............................................................23

5.2 STSW-AUTODEVKIT ..........................................................23

5.3 AEK-AUD-D903V1.c and sound.c drivers .........................................23

5.3.1 AEK-AUD-D903V1.c driver ................................................23

5.3.2 sound.c description ......................................................28

6 How to play an audio WAV file ....................................................30

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Contents

6.1 SPC582B60E1 memory map....................................................30

6.2 Uploading audio W

AV file ......................................................30

7 AEK-AUD-D903V1 sample applications............................................43

7.1 How to create a simple AEK-AUD-D903V1 application ..............................43

7.2 Available demos for AEK-AUD-D903V1...........................................49

7.2.1 How to upload the demos for AEK-AUD-D903V1 ...............................49

7.2.2 Mono audio – Test Application (SPC584Bxx and SPC58ECxx).....................51

7.2.3 I²C Software Mono audio – Test Application (SPC582Bxx and SPC58ECxx) ..........51

7.2.4 Mono audio and Diagnostic - Test Application (SPC582Bxx).......................51

7.2.5 Stereo audio and Diagnostic - Test Application (SPC582Bxx) ......................52

7.2.6 Engine Sound Simulator - Test Application for AVAS purpose (SPC582Bxx)...........52

Revision history .......................................................................55

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List of figures

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List of figures

Figure 1. A

Figure 2. AVAS demo hardware and connections ...................................................2

Figure 3. AEK-MCU-C1MLIT1 Discovery board components ...........................................3

Figure 4. Standard I²S data format .............................................................5

Figure 5. Connector CN10 pins for DSPI0 ........................................................5

Figure 6. I²C typical data format ............................................................... 6

Figure 7. Connector CN10 pins dedicated to I²C .................................................... 7

Figure 8. AEK-AUD-D903V1 main components and interfaces ..........................................8

Figure 9. FDA903D state machine ............................................................. 9

Figure 10. I²S (DSPI) connection in AEK-AUD-D903V1 ............................................... 11

Figure 11. I²C connection in AEK-AUD-D903V1 ....................................................12

Figure 12. ENABLE pin locations on the connector .................................................. 13

Figure 13. Read operation packet.............................................................. 14

Figure 14. Read operation required data .........................................................14

Figure 15. Read operation with repeated start condition .............................................. 14

Figure 16. Linear potentiometer circuit .......................................................... 17

Figure 17. Potentiometer connections ........................................................... 18

Figure 18. AVAS system for two stereo sound ..................................................... 19

Figure 19. AEK-MCU-C1MLIT1 seen on both sides ................................................. 20

Figure 20. AEK-AUD-C1D9031 components ......................................................21

Figure 21. API AEK_903D_Play(AEK_AUD_D903V0)................................................ 25

Figure 22. I2S Test Pin configuration API ........................................................ 25

Figure 23. playSound API ................................................................... 29

Figure 24. Project folder for audio files .......................................................... 31

Figure 25. Old flash block memory allocation ...................................................... 32

Figure 26. New flash block memory allocation .....................................................32

Figure 27. sounddb definition................................................................. 33

Figure 28. sounddb.s audio file declarations ...................................................... 34

Figure 29. Build output before adding sounddb.s component ........................................... 35

Figure 30. Build output after adding sounddb.s component ............................................ 35

Figure 31. Open hex file with editor ............................................................ 36

Figure 32. hex file data ..................................................................... 37

Figure 33. Starting point of audio content in hex file ................................................. 38

Figure 34. sounddb.s file with audio sample file paths removed ......................................... 39

Figure 35. SPC5-UDESTK-SW software with loader window ........................................... 40

Figure 36. FLASH/OTP Memory Programming Tool ................................................. 41

Figure 37. UDE Flash erase tool .............................................................. 41

Figure 38. SPC5-STUDIO adding audio project components ........................................... 43

Figure 39. AEK-AUD-D903V1 component configuration .............................................. 44

Figure 40. AEK-AUD-D903V1 I²C configuration ....................................................45

Figure 41. PinMap editor .................................................................... 46

Figure 42. SPC5-STUDIO Import application Wizard ................................................ 50

Figure 43. SPC5-STUDIO application library ...................................................... 51

Figure 44. Audio sample frequency modulation .................................................... 52

Figure 45. Varying sample numbers to simulate frequency modulation .................................... 53

VAS system AutoDevKit control board and audio board .......................................1

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List of tables

List of tables

T

able 1. I²C device address combinations .........................................................9

Table 2. Legacy mode Enable configurations ......................................................10

Table 3. I²C address 1 selection ...............................................................12

Table 4. Subaddress association .............................................................. 13

Table 5. IB register map .................................................................... 15

Table 6. DB register map.................................................................... 16

Table 7. Comparison of pin settings for addresses 1 and 3 ............................................ 20

Table 8. FDA903D IB8 register description ....................................................... 24

Table 9. list of API functions in AEK-AUD-D903V1.c ................................................. 26

Table 10. Flash memory map of SPC582B ........................................................ 30

Table 11. Document revision history ............................................................. 55

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