Nokia PermiCell18i System Module 04

PAMS Technical Documentation
TFK–2 Series Transceiver
Chapter 4

SYSTEM MODULE

Original, 05/98
PAMS
System Module
CHAPTER 4 – SYSTEM MODULE Contents
Introduction Page 4–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Technical Section Page 4–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
External Connections Page 4–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
System Connector X120 Page 4–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SIM Connector X300 Page 4–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Baseband Block Page 4–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction Page 4–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Modes of Operation Page 4–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Description Page 4–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Supply Page 4–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MCU Page 4–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MCU Flash Loading Page 4–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Flash, D430 Page 4–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SRAM D440 Page 4–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
EEPROM D445 Page 4–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MCU and Peripherals Page 4–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Baseband A/D Converter Channels usage in N450 and D420 Page 4–16
Audio Control Page 4–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DSP Page 4–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
RFI2 N450 Operation Page 4–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Receiver Timing and AGC Page 4–22. . . . . . . . . . . . . . . . . . . . . . . .
RF Transmitter Timing and Power Control Page 4–22. . . . . . . . . . .
SIM Interface Page 4–22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Line Adapter Page 4–24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Line Adapter Power Supply Page 4–25. . . . . . . . . . . . . . . . . . . . . . . . . .
Technical Documentation
RF Block Page 4–27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction Page 4–26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Receiver Page 4–26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pre–Filters Page 4–27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pre–Amplifier Page 4–27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
RX Interstage Filter Page 4–27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
First Mixer Page 4–28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
First IF Amplifier Page 4–28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
First IF Filter Page 4–28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2nd Mixer Page 4–28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2nd IF Amplifier Page 4–28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2nd IF Filter Page 4–29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Receiver IF Circuit, RX part of CRFRT Page 4–29. . . . . . . . . . . . . . . .
Last IF Filter Page 4–29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Transmitter Page 4–29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Modulator Circuit TX, part of CRFRT Page 4–30. . . . . . . . . . . . . . . . . .
Up–conversion Mixer Page 4–31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TX Interstage Filters Page 4–32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1st TX Buffer Page 4–32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2nd TX Buffer Page 4–32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Amplifier Page 4–32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Control Circuits Page 4–33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Frequency Synthesizers Page 4–34. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Reference Oscillator Page 4–34. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VHF PLL Page 4–35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VHF VCO + Buffer Page 4–35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UHF PLL Page 4–36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UHF VCO + Buffer Page 4–36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UHF VCO Buffers Page 4–36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PLL Circuit Page 4–37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interconnection Diagram of Baseband Page 4–38. . . . . . . . . . . . . . . . . . . . .
System Module
Block Diagram of RF Page 4–39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
RF Frequency Plan Page 4–40. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Distribution Diagram of RF Page 4–41. . . . . . . . . . . . . . . . . . . . . . . . .
Parts list of WT7 (EDMS Issue 2.6) Page 4–42. . . . . . . . . . . . . . . . . . . . . . . .
Parts list of WT7 (EDMS Issue 2.6) Page 4–43 Schematic Diagrams:
Block Diagram of Baseband (Version 2.2 Edit 144) 4/A3–1. . . . . . . . .
Circuit Diagram of Power Supply (Version 2.2 ; Edit 45) 4/A3–2. . . . .
Circuit Diagram of Line Adapter Power Supply Unit (Ver 2.2 ; Edit 104) 4/A3–3 Circuit Diagram of 2 to 4 Wire Interface (Version 2.2 ; Edit 127) 4/A3–4
Circuit Diagram of Connectors (Version 2.2 ; Edit 65) 4/A3–5. . . . . . .
Circuit Diagram of MCU Memory Block (Version: 2.2 ; Edit 47) 4/A3–6
Circuit Diagram of Audio (Version: 2.2 ; Edit 90) 4/A3–7. . . . . . . . . . .
Circuit Diagram of ASIC (Version: 2.2 ; Edit 39) 4/A3–8. . . . . . . . . . . .
Circuit Diagram of DSP Memory Block (Version: 2.2 ; Edit 31) f 4/A3–9
Circuit Diagram of RFI (Version: 2.2 ; Edit 71) 4/A3–10. . . . . . . . . . . . . .
Circuit Diagram of Receiver (Version: 2.2 ; Edit 224) 4/A3–11. . . . . . . .
Circuit Diagram of Transceiver (Version: 2.2 ; Edit 264) 4/A3–12. . . . . .
Layout Diagram of WT7 (Version: 03) 4/A3–13. . . . . . . . . . . . . . . . . . . . .
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System Module

Introduction

WT7 is the baseband/RF module of the TFK–2 transceiver. The WT7 module
comprises all the system and RF functions of the transceiver. The system
module WT7 is designed for a Fixed Wireless terminal operating in the GSM
1800 system.
Technical Section
All functional blocks of the system module are mounted on a single multi layer
printed circuit board. The chassis of the radio unit has separating walls for
baseband and RF. The connections to accessories are taken through the sys-
tem connector of the radio unit. There is no physical connector between the
RF and baseband sections.

External Connections

The system module has two connectors, an external system connector, and
SIM connector.
Technical Documentation

System Connector X120

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Technical Documentation
System Module
System Connector X120 Connector
Pin Name Parameter Min Typ Max Unit Remark
1 MBUSRX Serial
RX
2 MBUSTX Serial
TX
3 MBUSSCK Serial
Clock
4 BOOT-
MODE
5 PCMDCLK Audio
Clock
6 MBUS Serial
Control
Bus
7 VPP Pro-
gram-
ming
voltage
”0” ”1”
”0” ”1”
”0” ”1”
”0” ”1”
”0” ”1”
”0” ”1”
Active
Inactive
0
2.4 0
2.4 0
2.4 0
2.4 0
2.4 0
2.4
11.6 0
0.6
3.2
0.6
3.2
0.6
3.2
0.6
7.15
0.6
3.2
0.5
3.2
12 12.6
3.2
V
Receive data for serial com-
V V
V V
V V
V V
V V
V V
V
Serial Clock for synchro-
munication
Transmit data for serial
communication
nous communication /
RS_RTS
Normal mode
Flash mode
512 kHz clock for audio
data
Serial bidirectional
control bus.
Baud rate 9600 bit/s.
Programming voltage is
applied before entering
the programming state
8 DBUS_RXD DBUS
Inter-
face
9 DBUS_TXD DBUS
Inter-
face
10 PCMSCLK Audio
Clock
11 VL Logic Supply
Voltage
12 TX FBUS
TX
13 RX FBUS
RX
14 VBA TT Battery Supply
Voltage 15 DGND 0 V Digital GND 16 RS_CTS RS232 ”0”
17 PWRONX Service
Hand-
set
”0” ”1”
”0” ”1”
”0” ”1”
”0” ”1”
”0” ”1”
”1”
Active
Inactive02.4
0
2.4 0
2.4 0
2.4
0
2.4 0
2.4
6.6 6.75 6.9 V Battery voltage
0
2.4
0.6
3.2
0.6
3.2
0.6
3.2
3.2 V 3 V Logic voltage
0.5
3.2
0.6
3.2
0.5
3.2
0.5
3.2
V V
V V
V V
V V
V V
V V
V V
Receive data for DAI
Transmit data for DAI
8 kHz slot clock for audio
data
FBUS Transmit
FBUS Receive
Pull–up on Base Band
Handshake signal for
RS–232 serial interface
Power ON key from service
handset
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18 AGND Signal ground 0 V Analog GND
19 XMIC External Micro-
phone Input
20 XEAR External Speaker 0 32 500 mV Audio out
8 50 mV Audio in
Technical Documentation
RemarkUnitMaxTypMinParameterNamePin
Measuring Reference for
Audio signals.
47 ohm to Audio ground
Connected to Audio Codec
Inverted Output.
Typical level corresponds to
–16 dBm0 network level
with volume control in
nominal position 8dB below
maximum.
Maximum 0 dBm0 max.
Volume codec gain –6 dB

SIM Connector X300

Pin: Name: Description: 1 GND Ground for SIM
2 VSIM SIM voltage supply
3.16 / 4.8 V 3 SDATA Serial data for SIM 4 SRES Reset for SIM 5 CLK Clock for SIM data (clock frequency minimum
1 MHz if clock stopping not allowed)
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Technical Documentation

Baseband Block

Introduction

The WT7 module is used in TFK–2 product. The baseband is built around one DSP, System ASIC and the MCU. The DSP performs all speech and GSM re­lated signal processing tasks. The baseband power supply is 3V, except for the A/D and D/A converters that are the interface to the RF section, and to the comparators in the LAPWRU.
The audio codec is a separate device which is connected to both the DSP and the MCU. The audio codec supports the internal audio from line adapter and external audio from the service handset.
The baseband clock reference is derived from the RF section, and the refer­ence frequency is 13 MHz. A low level sinusoidal wave form is fed to the ASIC which acts as the clock distribution circuit. The DSP is running at 39 MHz using an internal PLL. The clock frequency supplied to the DSP is 13 MHz. The MCU bus frequency is the same as the input frequency. The system ASIC provides both 13 MHz and 6.5 MHz as alternative frequencies. The MCU clock frequen­cy is programmable by the MCU. The baseband uses 13 MHz as the MCU op­erating frequency. The RF A/D, D/A converters are operated using the 13 MHz clock supplied from the system ASIC
System Module
The power supply IC contains three different regulators. The output voltage from each regulator is 3.15V nominal. One of the regulators uses an external transistor as the boost transistor.
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Modes of Operation

The baseband can operate only in the active mode in WLL terminal.

Circuit Description

Power Supply
+6.6 V
5,21,44,39,37
VBAT
N300
43
35
40
V300
Technical Documentation
VBATT
+6.6 V
VL +3.2V VA +3.2 V
VSL +3.2 V
DGND
4,20,38
6,32
AGND
The baseband has one power supply circuit N300 delivering power to the differ­ent parts in the baseband. There are two logic power supplies and one analog power supply. The analog power supply VA is used for analog circuits such as audio codec. Due to the current consumption and the baseband architecture the digital supply is divided into to parts.
Both digital power supply VSL and VL from the N300 PSCLD are used to dis­tribute the power dissipation inside N300 PSCLD. The main logic power supply VL has an external power transistor, V300 to handle the power dissipation.
D400, ASIC, and the MCU SRAM D440 are connected to the same logic supply voltage. All other digital circuits are connected to the main digital supply. The analog voltage supply is connected to the audio codec.
N350
VCC
+5.0 V
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Technical Documentation
Power Supply Regulator PSCLD, N300
The power supply regulators are integrated into the same circuit N300. The power supply IC contains three different regulators. The main digital power sup­ply regulator is implemented using an external power transistor V300. The oth­er two regulators are completely integrated into N300.
PSCLD, N300 External Components
N300 performs the required power–on timing. The PSCLD N300 internal pow­er on and reset timing is defined by the external capacitor C318. This capacitor determines the internal reset delay, which is applied when the PSCLD N300 is initially powered by applying the power supply. The baseband power–on delay is determined by C315. With a value of 10 nF, the power–on delay after a pow­er–on request has been active is in the range of 50–150 ms. C311 determines the PSCLD N300 internal oscillator frequency, and the minimum power–off time when power is switched off.
The sleep control signal from the ASIC D400 is connected via PSCLD N300. During normal operation, the baseband sleep function is controlled by the ASIC D400, but since the ASIC is not powered up during the startup phase, the sleep signal is controlled by PSCLD N300 as long as the PURX signal is active. This arrangement ensures that the 13 MHz clock provided from RF to the ASIC D400 is started and stable before the PURX signal is released, and the base­band exits reset. When PURX is inactive high, the sleep control signal is con­trolled by the ASIC D400.
System Module
N300 requires capacitors on the input power supply as well as on the output from each regulator to keep each regulator stable during different load and tem­perature conditions. Due to EMC precautions, a filter using C301, L302 and L303 has been inserted into the supply rail. This filter reduces the high frequen­cy components present at the VBAT from exiting the baseband into the power supply. The regulator outputs also have filter capacitors for power supply filter­ing and regulator stability. A set of different capacitors are used to achieve a high bandwidth in the suppression filter.
PSCLD, N300 Control Bus
The PSCLD, N300 is connected to the baseband common serial control bus. This bus is a serial control bus from the ASIC D400 to several devices on the baseband. This bus is used by the MCU to control the operation of N300 and other devices connected to the bus. N300 has two internal 8 bit registers and the PWM register used for charging control. The registers contain information for controlling reset levels, charging HW limits, watchdog timer length, and watchdog acknowledgement.
The control bus includes three wires: clock, serial data, and chip select for each device on the bus. From the PSCLD N300 point of view, the bus can be used for writing only. It is not possible to read data from PSCLD N300 by using this bus.
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The MCU can program the HW reset levels when the baseband exits/enters re­set. The programmed values are retained until PSCLD N300 is powered off, i.e. the power supply is cut off. At initial power–on, when PSCLD is powered– on, the default reset level is used. The default value is 5.1 V, with the default hysteresis of 400 mV. This means that reset is exit at 5.5 V when the PSCLD N300 is powered for the first time.
The watchdog timer length can be programmed by the MCU using the serial control bus. The default watchdog time is 32 s with a 50 % tolerance. The com­plete baseband is reset if the watchdog is not acknowledged within the speci­fied time. The watchdog is running while PSCLD N300 is powering–up the sys­tem but PURX is active. This arrangement ensures that if for any reason the supply voltage doesn’t increase above the reset level within the watchdog time the system is reset by the watchdog. As the time PURX is active is not exactly known, and depends upon startup conditions, the watchdog is internally ac­knowledged in PSCLD when PURX is released. This gives the MCU always the same time to respond to the first watchdog acknowledge.
The PSCLD N300 also contains a switch for connecting and the supply voltage to the baseband A/D converters. The switch state can be changed by the MCU via the serial control bus. When PURX is active, the switch is open to prevent the supply voltage from being applied to the baseband measurement circuitry, which is powered off. Before any measurement can be performed, the switch must be closed by MCU.
Technical Documentation
SIM Interface and Regulator in N300
The SIM card regulator and interface circuit is integrated into PSCLD N300. The benefit from this is that the interface circuits are operating from the same supply voltage as the card, avoiding the voltage drop caused by the external switch used in previous designs. The PSCLD N300 SIM interface also acts as voltage level shifting between the SIM interface in the ASIC D400 operating at 3V and the card operating at 3V or 5V. Interface control in PSCLD is direct from ASIC, D400 SIM interface. The MCU can select the power supply voltage for the SIM using the serial control bus. The value can be either 3V or 5V de­pending on the SIM card. The defaiult value is 3V. The regulator enable and disable is controlled by the ASIC via SIMI(2).
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Power–Up Sequence
PSCLD N300
VBAT
Watchdog disable
R346
C351
5,21,37 39,44
25
22 28
30
16,18,19
C310
VL VSL VA
40 35
26 120
17 130 14
13
CRFCONT
N601
Purx
Serial Bus VCXO Enable
CHARGAlarm
1415
129
VCXO
SRAM, FLASH D440 D430
22
13 MHz
Address Bus
ASIC D400
Watchdog Register
32 kHz
125 126
Data Bus
System Module
83 84
MCU Clock
82
MCU Reset
81
48 51
DSP Reset
DSP Clock
MCU D420
Power–On Reset Operation
The system power–up reset is generated by the regulator IC N300. The reset is connected to the ASIC D400 that is reset whenever the reset signal PURX is low. The ASIC D400 then resets the DSP D360, the MCU D420, and the digi­tal parts in N450. When reset is removed, the clock supplied to the ASIC D400 is enabled inside the ASIC. At this point the 32 kHz oscillator signal is not en­abled inside the ASIC, since the oscillator is still in the startup phase. To start up the block requiring 32 kHz clock, the MCU must enable the 32 kHz clock. The MCU reset counter is now started and the MCU reset is still kept active low. A 6.5 MHz clock is started to MCU in order to put the MCU D420 into re­set. The MCU is a synchronous reset device and needs a clock to reset. The reset to MCU is set inactive after 128 MCU clock cycles, and MCU is started.
DSP D360 and N450 reset is kept active when the clock inside the ASIC D400 is started. A13 MHz clock is started to DSP D360 and puts it into reset. D360 is a synchronous reset device, and requires a clock to enter reset. The N450 digital parts are reset asynchronously and do not need a clock to be supported to enter reset.
As both the MCU D420 and DSP D360 are synchronous reset devices, all inter­face signals connected between these devices and ASIC D400 which are used as I/O are set into input mode on the ASIC D400 side during reset. This avoids bus conflicts occurring before the MCU D420 and the DSP D360 are actually reset.
The DSP D360 and N450 reset signal remains active after that the MCU has exited reset. The MCU writes to the ASIC register to disable the DSP reset. This arrangement allows the MCU to reset the DSP D360 and N450 whenever
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needed. The MCU can put DSP into reset by writing the reset active in the ASIC D400 register
MCU
The baseband uses a Hitachi H3001 type of MCU. This is a 16–bit internal MCU with 8–bit external data bus. The MCU is capable of addressing up to 16 MByte of memory space linearly, depending upon the mode of operation. The MCU has a non multiplexed address/data bus which means that memory ac­cess can be done using less clock cycles thus improving the performance but also tightening up memory access requirements. The MCU is used in mode 3 which means 8–bit external data bus and 16 Mbyte of address space. The MCU operating frequency is equal to the supplied clock frequency. The MCU has 512 bytes of internal SRAM. The MCU has one serial channel, USART that can operate in synchronous and asynchronous mode. The USART is used in the MBUS implementation. The clock required for the USART is generated by the internal baud rate generator. The MCU has 5 internal timers that can be used for timing generation. Timer TIOCA0 input pin 71 is used for generation of netfree signal from the MBUS receive signal which is connected to the MCU USART receiver input on pin 2.
Technical Documentation
The MCU contains 4 10–bit A/D converters channels that are used for base­band monitoring.
The MCU, D420 has several programmable I/O ports which can be configured by SW. In this case, the data bus lines D0–D7 are used for baseband control functions. It is not used as part of the data bus.
MCU Access and Wait State Generation
The MCU can access external devices in 2 state access or 3 state access. In two state access the MCU uses two clock cycles to access data from the exter­nal device In 3 state access the MCU uses 3 clock cycles to access the exter­nal device or more if wait states are enabled. The wait state controller can op­erate in different modes. In this case, the programmable wait mode is used. This means that the programmed amount of wait states in the wait control reg­ister are inserted when an access is performed to a device located in that area. The complete address space is divided into 8 areas each area covering 2 MByte of address space. The access type for each area can be set by bits in the access state control register. Furthermore, the wait state function can be enabled separately for each area by the wait state controller enable register.
This means that in 3 state access, two types of access can be performed with a fixed setting:
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– 3 state access without wait states – 3 state access with the amount of wait states inserted determined by the
wait control register
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Technical Documentation
If the wait state controller is not enabled for a 3 state access area, no wait states are inserted when accessing that area even if the wait control register contains a value that differs from 0 states.
MCU Flash Loading
The flash loading equipment is connected to the baseband by means of the service adapter. The power supply for the baseband is supplied via the adapter and controlled by the flash programming equipment. The baseband module is powered up when the power is connected to the power supply connector.
Five signals are required for the flash programming, with the addition of the power supply. The baseband MCU will automatically wait for flash down–load­ing to be performed if one of the two following criteria are met.
– The flash is found to be empty when tested by the MCU – The serial clock line at the baseband MCU is forced low when the MCU is
exiting reset
The second alternative is used for reprogramming as the flash is not empty in this case. To allow the serial clock line to be forced low during MCU initial boot there is a requirement that the flash prommer can control the power on of the baseband module. This is done by controlling the switching of the power sup­ply. This arrangement allows the baseband module to operate in normal mode even if the flash prommer is connected but not active. The flash prommer also disables the power supply watchdog during flash programming to prevent un­wanted reset of the baseband. The programming voltage to the flash is applied when the flash prommer has detected that the baseband module is powered. This detection is performed by monitoring the serial interface RS_RX line from the baseband. The RS_RX line is pulled high by a pull–up resistor in idle. The VPP voltage is set to 5V as it is not known at this point what type of device is used.
System Module
The following diagram shows the block diagram for the baseband flash pro­gramming circuitry.
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PAMS
System Module
X120
7
VPP
1
RS_RX
2
RS_TX
3
SCK_RTS
4
WDDis
15
GND
VBAT
Flash Prommer
5... 22
PSCLD N301
26
VL,VSL
40
FLASH pin11 Vpp
PSCLD pin 22 WDDis
GND Programming Voltage Vpp
ASIC pin 120
PurX
ASIC pin 130 PwrDown
VLC
R436
11
FLASH D430
ASIC pin 51 CSelX
2,71 1
3
MCU pin 55 RdX
MCU D420
Internal RAM
38(9)37(24)9(24)12(10)
MCU pin 56 WrX
Technical Documentation
PSCLD pin 26 PurX
Master Reset 56 55
MCUResX
51 82
MCUClk
MCUAdrress
MCUData
WrX RdX
SRAM D440
55 56 8148
49
RAMCSelX
30
5
32
120
ASIC D400
BOOT ROM
MCU pin 56 WrX
MCU pin 55 RdX
The interface lines between the flash prommer and the baseband are in low state when power is not connected by the flash prommer. The data transfer be­tween the flash programming equipment and the base band is synchronous, and the clock is generated by the flash prommer. The same MCU USART that is used for MBUS communication is used for the serial synchronous commu­nication. The PSCLD watchdog is disabled when the service adapter and flash prommer are connected.
After the service adapter has been connected to the board the power to the baseband module can be connected by the flash prommer or the test equip­ment. All interface lines are kept low, except for the data transmit from the baseband that is in reception mode on the flash prommer side, this signal is called RS_TX. The MCU boots from ASIC and investigates the status of the synchronous clock line. If the clock input line from the flash prommer is low or no valid SW is located in the flash, MCU forces the initially high RS_TX line low acknowledging to the flash prommer that it is ready to accept data.
The flash prommer sends data length, 2 bytes, on the RS_RX data line to the baseband. The MCU acknowledges the 2 data byte reception by pulling the RS_TX line high. The flash prommer now transmits the data on the RS_RX line to the MCU. The MCU loads the data into the internal SRAM. After having re­ceived the transferred data correctly MCU puts the RS_TX line low and jumps into internal SRAM and starts to execute the code. After a guard time of 1 ms the RS_TX line is put high by the MCU. After 1 ms the RS_TX is put low indi­cating that the external SRAM test is going on. After a further 1 ms, the RS_TX is put high indicating that external SRAM test has passed. The MCU performs
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PAMS
Technical Documentation
the flash memory identification based upon the identifiers specified in the Flash Programming Specifications. In case of an empty device, identifier locations shows FFH, the flash device code is read and transmitted to the Flash Prom­mer.
Internal SRAM
Reset
RS_TX
Boot OK
Length OK
execution begin External SRAM
External SRAM test going on
1 ms
System Module
Ready to send
Flash ID
test passed
After that, the device mounted on baseband has been identified, and the Flash Prommer down–loads the appropriate algorithm to the baseband. The pro­gramming algorithm is stored in the external SRAM on the baseband module, and after having down–loaded the algorithm and data transfer SW, the MCU jumps to the external SRAM and starts to execute the code.
The MCU now asks the prommer to connect the flash programming power sup­ply. This SW loads the data to be programmed into the flash, and implements the programming algorithm that has been down loaded.
Flash, D430
A 8 MBit Boot Block flash is used as the main program memory D430. The de­vice is 3 V read/program with external 12V VPP for programming. The device has a lockable boot sector. This function is not used since the complete code is reprogrammed. The Boot sector is located at the ”bottom”, definition by Intel, address 00000H–03FFFH. The block is unlocked by a logic high state on pin
12. This logic high level is generated from VPP. The device can be pro­grammed by a VPP of 5V but the programming procedure takes longer. To im­prove programming, the programming voltage used is 12V. The speed of the device is 150 ns.
SRAM D440
The baseband is designed to take a 128k x 8 SRAM. The SRAM has no bat­tery backup which means that the content is lost even during short power sup­ply disconnections. As shown in the memory map, the SRAM is not accessible after boot until the MCU has enabled the SRAM access by writing to the ASIC register.
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PAMS
System Module
EEPROM D445
The baseband is designed to take an 8kx8 serial EEPROM. TFK–2 will use the 8kx8 serial device over the I2C bus. The I2C bus protocol is implemented in SW and the physical implementation is performed on MCU Port 4.
MCU and Peripherals
MCU Port P4 Usage
MCU, D420 port 4 is used for baseband control. Port Pin MCU pin Control Function Remark
P40 5 SLIC–CTRL 0 P41 6 SLIC–CTRL 1 P42 7 SLIC–CTRL 2 P43 8 RS_DSR P44 9 EEPROM SCK
Technical Documentation
P45 10 EEPROM SDA P46 11 EEPROM write enable Active low P47 12 RS_CTS
Baseband A/D Converter Channels usage in N450 and D420
The auxiliary A/D converter channels inside RFI2 N450 are used only for mea­suring of the system board temperature by the MCU.
The MCU has 4 10 bit A/D channels which are used for baseband voltage mon­itoring. The MCU can measure supply voltage, accessory detection (ID), loop current (IBBDET) and SMPS output voltage (VBBDET) by using it‘s own con­verters.
Baseband N450 A/D Converter Channel Usage
Name: Usage: Input volt. range Chan 0 System board temperature 0...3.2 V
Chan 1–7 not used
MCU Baseband A/D Converter Channel Usage
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Name: Usage: Input volt. range Chan 0 Supply voltage 0...3.2 V
Chan 1 Accessory detection 0...3.2 V Chan 2 IBBDET 0...3.2 V Chan 3 VBBDET 0...3.2 V
Original 05/98
PAMS
Technical Documentation
Supply Voltage Measurement
The supply voltage is measured using MCU N420 A/D converter channel 0. The supply voltage supplied to the A/D converter input is switched off when the baseband is powered off. The supply voltage measurement voltage is supplied by PSCLD N300, which performs switch–off, and scaling with a scaling factor of R1(R1+R2). The measurement voltage is filtered by a capacitor to achieve an average value that is not depending upon the current consumption behavior of the baseband. To be able to measure the supply voltage during transmission pulse, the time constant must be short. The value for the filtering capacitor is set to 1 nF C319. The scaling factor used to scale the supply voltage must be 1:3, which means that a 9V supply voltage will give 3V A/D converter input voltage. The A/D converter value in decimal can be calculated using the follow­ing formula:
A/D = 1023xR1xU
BAT
where K is the scaling factor. K = R1/((R1+R2)xU
Audio Control
/((R1+R2)xU
) = 1023xU
ref
BAT
ref).
System Module
xK
LATX
XEAR
LARX
The audio codec N130 is controlled by the MCU D420. The ASIC generates a 512 kHz data clock, and a 8 kHz synchronization signal for the PCM data bus. Data is put out on the bus at the rising edge of the clock and read in at the fal­ling edge. Data from the DSP D360 to the audio codec N130 is transmitted as a separate signal from data transmitted from the audio codec, N130 to the DSP D360. The communication is full duplex synchronous. The transmission is started at the falling edge of the synchronization pulse. 16 bits of data is trans­mitted after each synchronization pulse.
R132
C129
31
R113
EXT EQUIPM. INDICATION
R131
MCU D420
293727
DSP D360
XMIC
!D
MCU pin 64
A/D Converters
Data, Addr Bus
IRQ1X 68
78
42,44,46
40 41
ASIC
D400
3341
122
Data, Addr Bus
R115
C134
C132
R133 C133
C135
14
8
6
25
24
CODEC
N130
CLK CSX DATA
11 12
13,16
23
22
20 19
10 17
C140
Serial Bus
AUDIO DATA IN AUDIO DATA OUT
X120
SYSTEM CONNECTOR
17
C137
CLK 512 kHz SYNC 8 kHz
VLC
Original 05/98
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PAMS
System Module
The 512 kHz clock is generated from 13 MHz using a PLL type of approach, which means that the output frequency varies as the PLL adjusts the frequency. The average frequency is 512 kHz. The clock is not supplied to the codec when it is not needed. The clock is controlled by both MCU and DSP. DTMF tones are generated by the audio codec and for that purpose, the 512 kHz clock is needed. The MCU must switch on the clock before the DTMF generation con­trol data is transmitted on the serial control bus.
The serial control bus uses clock, data, and chip select to address the device on the bus. This interface is built into the ASIC, and the MCU writes the des­tination and data to the ASIC registers. The serial communication is then initi­ated by the ASIC. Data can be read form the audio codec N130 via this bus.
DSP
The DSP used in TFK–2 is the TI 320LC546. This is a 16 bit DSP that can use external and/or internal memory access. The DSP can operate in two modes microprocessor mode or micro–controller mode. The difference between the two modes is that in microprocessor mode the DSP boots from external memory, while in the micro–controller mode the DSP boots from internal ROM. The DSP external memory access is divided into data, program, and I/O ac­cess. The type of access is indicated on three control pins that can be used for memory control.
Technical Documentation
The DSP D360 executes code from the internal ROM. The baseband also pro­vides external memories for the DSP, D371, D372, D381, and D382 (Note: These memories are not fitted in all transceivers). The DSP is capable of ad­dressing 64 kword of memory. The memory area is divided into a code execu­tion area and a data storage area. The code execution area is located at ad­dress 4000H–FFFFH in the internal ROM. The external memories are arranged in such a way that the DSP can access the external memories both as data storage and code execution. The memory chip select is taken from the memory access strobe signal from the DSP. This means that the memory is active dur­ing any memory access. The SRAMs are configured in chip select controlled write mode. This means that both the write signal and the output enable signal are active at the same time, and the actual write occurs at the rising edge of the chip select signal. This implementation is required since the DSP supports only one signal for write/read control.
The DSP is operating from the 13 MHz clock. In order to get the required per­formance, the frequency is internally increased by a PLL by a factor of 3. The PLL requires a settling time of 50 us after that the clock has been supplied be­fore proper operation is established. This settling counter is inside the DSP al­though the ASIC D400 contains a counter that will delay the interrupt with a programmable amount of clock cycles before the interrupt causing the clock to be switched on is presented to the DSP. The DSP has full control over the clock supplied to it. When the DSP is to enter the sleep mode the clock is switched off by setting a bit in the ASIC register. The clock is automatically switched on when an interrupt is generated.
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