The tire pressure monitoring system (referred as TG for Tire Guard) consists of the following
u
nits:
- Tire guard wheel unit type TIS-03 which includes an integrated pressure, temperature and
acceleration sensor and a RF transmitter.
- LF receiver unit which includes a LF receiver (not described in this document)
The TG monitors a vehicle's tire pressure while driving or stationary. An electronic unit (wheel
unit) inside each tire, mounted to the valve stem, periodically measures the actual tire pressure.
By means of RF communication, this pressure information is transmitted to the RF transmitter.
. TECHNICAL DESCRIPTION
2
Carrier frequency: 433.92 MHz
Number of channels: 1
Type of modulation: Frequency Shift Keying (FSK)
Baud rate: 9600bps
Rated Output Power: < 10mW
Antenna: Internal
Voltage supply range : 2.1 up to 3.2V
3. TYPICAL USAGE PATTERN
3.1 AVERAGE FACTOR CALCULATION (Standard 47 CFR Part 15C (periodic
intentional transmitter))
Maximum transmitting duration in whatever 100ms windows: 10.31ms
Averaging factor = 20xlog(10.31/100)=-19.73dB
Note : The time between inter frames is always higher than the 100ms FCC window.
BLOCK DIAGRAM
4.
The block diagram below shows the main electronic units of the wheel unit:
Sensor Block Diagram
FXTH870x5
(P ress ure ,
te m per a tur e,
a cce le rat io n se ns o r,
µ co nt roll er & R F
T ran s m i tte r)
C rys tal :2 6M Hz
4 3 3. 92M H z o r 3 1 5M H z
R F C IRC UI T
(T un n in g
C om pon en ts)
A NT E NN A
Le ar nin g LF co il
(1 a xe C oil @
1 25 KH z)
L I TH I UM
B A TT E RY
3 V
C R 20 5 0H R
2
of 4
IC Block Diagram: FXTH870x5
he FXTH870x5 contains:
T
• Microcontroller with accelerometer and pressure sensor interfaces,
and RF transmitter (MCU)
• Optional ranges on pressure transducers
• Z-axis acceleration transducer
The MCU interfaces to the RF transmitter using a standard memory mapped registers. The
transducers connect to the MCU using custom analog interfaces and inter-chip bonding wires.
5. PICTURE
3
of 4
6. LABEL
1.1. U
SA
Continental
TIS-03
FCC ID: KR5TIS-03
his device complies with Part 15 of the FCC Rules. Operation is subject to the following
T
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.
1.2. CANADA
Continental
TIS-03
IC: 7812D-TIS03
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.
4
of 4
FXTH870x6
Top and bottom view
Top view
Pin connections
24-Pin, 1-hole lid
7 x 7 QFN
20
21
22
23
24
18
PTA3
LFA
LFB
BKGD/PTA4
X0
X1
17
19
2
3
4
5
6
7
PTB1
PTA2
PTA1
8
1
RESET
10
11
12
13
14
15
V
DD
V
DDA
V
SSA
V
REG
RF
16
9
PTB0
N/C
N/C
N/C
N/C
N/C
ID Feature
on top lid
PTA0
V
SS
RFV
SS
Freescale SemiconductorDocument Number: FXTH870x6
Data Sheet: Advance InformationRev. 1.5, 02/2015
An Energy-Efficient Solution by Freescale
FXTH870x6 Tire Pressure Monitor
Sensor
The FXTH870x6 family is comprised of the following functions all within the
same package.
Features
•Pressure sensor with one of two calibrated pressure ranges
— 100 - 450 kPa
— 100 - 900 kPa
•Temperature sensor
•Optional XZ- or Z-axis accelerometer with adjustable offset option
•Voltage reference measured by ADC10
•Six-channel, 10-bit analog-to-digital converter (ADC10) with two external
I/O inputs
•8-bit MCU
— S08 Core with SIM and interrupt
— 512 RAM
— 8K FLASH (in addition to 8K providing factory firmware and trim
•Dedicated state machines to sequence routine measurement and
transmission processes for reduced power consumption
•Internal 315-/434-MHz RF transmitter
•Differential input LF detector/decoder on independent signal pins
•Seven multipurpose GPIO pins
•Real-Time Interrupt driven by LFO with interrupt intervals of
8, 16, 32, 64, 128, 256, 512 or 1024 ms
•Low-power, wakeup timer and periodic reset driven by LFO
•Watchdog timeout with selectable times and clock sources
•Two-channel general purpose timer/PWM module (TPM1)
This document contains information on a new product. Specifications and information herein
are subject to change without notice.
— External crystal oscillator
— PLL-based output with fractional-n divider
— OOK and FSK modulation capability
— Programmable data rate generator
— Manchester, Bi-Phase or NRZ data encoding
— 256-bit RF data buffer variable length interrupt
— Direct access to RF transmitter from MCU for unique formats
— Low power consumption (less than 8 mA at 434 MHz, 5 dBM at
3.0 V, 25 °C)
— Four pins can be connected to optional internal pullups/pulldowns and STOP4 wakeup interrupt
— Two of seven pins can be connected to a channel on the ADC10
— Two of seven pins can be connected to a channel on the TPM1
•Internal oscillators
Related Documentation
The FXTH870x6 device features and operations are described in a variety of reference manuals, user guides, and application
notes. To find the most-current versions of these documents:
1.Go to the Freescale homepage at:
http://www.freescale.com/
2.In the Keyword search box at the top of the page, enter the device number FXTH870x6.
— MCU bus clock of 0.5, 1, 2 and 4 MHz (1, 2, 4 and 8 MHz HFO)
— Low frequency, low power time clock (LFO) with 1 ms period
— Medium frequency, controller clock (MFO) of 8 sec period
•Low-voltage detection
•Normal temperature restart in hardware (over- or under-temperature detected by software)
ORDERING INFORMATION
Part numberAccelerometer axisPackageRangeCode1
FXTH8705026T1Z2264 (7 x 7, 1-hole lid)100-450 kPa$08
FXTH8705116T1XZ2264 (7 x 7, 1-hole lid)100-450 kPa$0C
FXTH8709026T1Z2264 (7 x 7, 1-hole lid)100-900 kPa$18
FXTH8709116T1XZ2264 (7 x 7, 1-hole lid)100-900 kPa$1C
FXTH8709126T1XZ Ext. Range2264 (7 x 7, 1-hole lid)100-900 kPa$1E
Code1Code0
FXTH8709226T1XZ2264 (7 x 7, 1-hole lid)100-900 kPa$1CRel11
The block diagram of the FXTH870x6 is shown in Figure 1. This diagram covers all the main blocks mentioned above and their
main signal interactions. Power management controls and bus control signals are not shown in this block diagram for clarity.
1.2Multi-Chip Interface
The FXTH870x6 contains two to three devices using the best process technology for each.
•Microcontroller with accelerometer and pressure sensor interfaces, and RF transmitter (MCU)
•Optional ranges on pressure transducers
•Optional XZ- or Z-axis acceleration transducer
As shown in Figure 1 the MCU interfaces to the RF transmitter using a standard memory mapped registers. The transducers
connect to the MCU using custom analog interfaces and inter-chip bonding wires.
1.3System Clock Distribution
The various clock sources and their distribution are shown in Figure 2. All clock sources except the low frequency oscillator, LFO,
can be turned off by software control in order to conserve power.
FXTH870x6
Sensors
6Freescale Semiconductor, Inc.
8K USER
FLASH
MEMORY
RAM
MEMORY
512
TPM1
TIMER/PWM
2-CHAN
LVD
RTI
TIMER
MCU CORE
S08
AV
DD
TEMP
AV
DD
AV
SS
TEMP
SENSOR
PRESS
SENSOR
BANDGAP
REF
LFA
PTA1
ADC10
10-BIT
6-CHAN
TEMP
BKGD
/
LFB
64 Byte
PARAMETER
REGISTER
DATA
ENCODE
BIT
RATE
256-BIT
DATA
BUFFER
RF
AMP
VCO/PLL
FRACTL
DIVIDER
XTAL
OSC
XI
XO
RF
MCU
TRANSDUCERS
VOLT
REG
RESTART
OSC
GEN
PWU
TIMER
MFO
8 Sec
RESET
LF
RECVR
D
X
V
SENS
V
TP
V
0
LFO
1 ms
LFI
SMI
Z
HFO
1, 2, 4 or 8
MHz
GP
I/O
KEY
KBI
BOARD
WAKEUP
MFO
8K
FIRMWARE
MEMORY
PTA0
P
SENSOR MEASUREMENT
(SMI)
RF CONTROLLER
INTERF A CE
LFO
(LFR)
RFM
V
REG
PTA2
V
DD
V
DD
V
SS
RV
SS
PTA3
V
1
V
2
RF LVD
AV
DD
RFV
DD
V
REG
PTB0
PTB1
PTA4
XZ
XZ
ACCEL
(OPTION)
Z
ACCEL
(OPTION)
Figure 1. FXTH870x6 Overall Block Diagram
FXTH870x6
Sensors
Freescale Semiconductor, Inc.7
RTI
SYSTEM
CONTROL
LOGIC
2
HFO OSC
1, 2, 4,
f
OSC
f
BUS
CPU
BDC
TPM1
RAMFLASH
LFR
ADC10
MFO
OSC
8 Sec
PWU
CLSA, CLKSB
f
LFO
(1 kHz)
XTL
OSC
26 MHz
XIXO
PLLVCO
BIT
RATE
DATA
BUFFER
PRESSURE
SENSOR
TRANSDUCERS
MCU
RTICLKS
PAR
REG
f
MFO
f
XCO
GEN
D
X
(500 kHz)
LFO
OSC
1 mS
PERIOD
SENSOR MEASUREMENT
INTERFACE
ADC10
CLOCK
ADCCLKADC10
BUSCLKS[1:0]
WATCH
DOG
COPCLKS
Z-AXIS
SENSOR
LF
4 kbps
(125 kHz)
RF STATE
MACHINE
LFRO
OSCILL
8
TCLKDIV
LFOSEL
f
MFO
PTA3
PTA2
f
LFO
(1 kHz)
CH0CH1
RANDOM
(0 - 1 MHz)
RANDOM
(0 - 1 MHz)
RF
OUT
41.67 kHz
Sampling
41.67 kHz
Sampling
and 8 MHz
X-AXIS
SENSOR
41.67 kHz
Sampling
Figure 2. Clock Distribution
1.4Reference Documents
The FXTH870x6 utilizes the standard product MC9S08 CPU core. The user can obtain further detail on the full capabilities of this
core by referring to the HCS08 Family Reference Manual (HCS08RMV1).
FXTH870x6
8Freescale Semiconductor, Inc.
Sensors
2Pins and Connections
20
21
22
23
24
18
PTA3
LFA
LFB
BKGD/PTA4
X0
X1
17
19
2
3
4
5
6
7
PTB1
PTA2
PTA1
8
1
RESET
10
11
12
13
14
15
V
DD
V
DDA
V
SSA
V
REG
RF
16
9
PTB0
N/C
N/C
N/C
N/C
N/C
ID Feature
on top lid
PTA0
V
SS
RFV
SS
N/C = No Connect: Do not connect PCB pads to signal traces, power/ground or multi-layer via.
Top View
BKGD/PTA4
X-AXIS
ORIENTATION
+X
-X
Y-AXIS
ORIENTATION
+Y
-Y
Side View
Pressure
Port
POSITIVE ACCELERATION MOVES MASS
IN +Z DIRECTION (VALUE INCREASES)
Z-AXIS
ORIENTATION
+Z
-Z
This section describes the pin layout and general function of each pin.
2.1Package Pinout
The pinout for the FXTH870x6 device QFN package is shown in Figure 3 for the orientation of the pressure port up. The
orientation of the internal Z-axis accelerometer is shown in Figure 4.
Figure 3. FXTH870x6 QFN Package Pinout
2.2Recommended Application
Example of a simple OOK/FSK tire pressure monitors using the internal PLL-based RF output stage is shown in Figure 5. Any of
the PTA[3:0] pins can also be used as general purpose I/O pins. Any of the PTA[3:0] pins that are not used in the application
should be handled as described in Section 6.1.
L1 and matching network
optimized for specific PWB and
antenna layout. Recommend
0603 minimum size for L1 and
other matching network inductors
for maximum efficiency.
C1 and R1 optimized
for coil used, but
recommended
RC < 15.3 sec.
The device C
4
, although drawn here as a capacitor, may be any type of passive component(s) sufficient to block
or reduce unwanted external radiated signals from corrupting the crystal oscillator circuit: PCB traces for the LFA
/ LFB, A V
DD
/ VDD, and VSS / A VSS pins and bypass capacitors should be minimized to reduce unw anted external
radiated signals from corrupting the power input circuits.
The following sections describe the general function of each pin.
2.3.1VDD and VSS Pins
The digital circuits operate from a single power supply connected to the FXTH870x6 through the VDD and VSS pins. VDD is the
positive supply and V
locally decoupled as shown in Figure 6.
Care should be taken to reduce measurement signal noise by separating the V
connection such that each metal trace does not share any load currents with other external devices as shown in Figure 6.
2.3.2AVDD and AVSS Pins
is the ground. The conductors to the power supply should be connected to the VDD and VSS pins and
SS
Figure 5. FXTH870x6 Example Application
The analog circuits operate from a single power supply connected to the FXTH870x6 through the AVDD and AVSS pins. AVDD is
the positive supply and AVSS is the ground. The conductors to the power supply should be connected to the AVDD and AVSS pins
and locally decoupled as shown in Figure 6.
, VSS, A VDD, A VSS and RVSS pins using a “star”
DD
FXTH870x6
10Freescale Semiconductor, Inc.
Sensors
Care should be taken to reduce measurement signal noise by separating the V
0.1 µF
FXTH870xxx
V
DD
V
SS
to other
Battery
I
DD
I
LOAD
Bypass capacitors
closely coupled to
the package pins
FXTH870xxx and Other Load Currents
star connected to battery terminals
loads
0.1 µF
AV
DD
AV
SS
RV
SS
The decoupling devices, although
drawn here as 0.1 F capacitors,
may be any type of passive component(s)
sufficient to block or reduce unwanted
external radiated signals from corrupting
the power input protection circuits;
application tuning may be required.
connection such that each metal trace does not share any load currents with other external devices as shown in Figure 6.
Figure 6. Recommended Power Supply Connections
, VSS, A VDD, A VSS and RVSS pins using a “star”
DD
2.3.3V
The internal regulator for the analog circuits requires an external stabilization capacitor to AVSS.
REG
Pin
2.3.4RVSS Pin
Power in the RF output amplifier is returned to the supply through the RVSS pin. This conductor should be connected to the power
supply as shown in Figure 6 using a “star” connection such that each metal trace does not share any load currents with other
supply pins.
2.3.5RF Pin
The RF pin is the RF energy data supplied by the FXTH870x6 to an external antenna.
2.3.6XO, XI Pins
The XO and XI pins are for an external crystal to be used by the internal PLL for creating the carrier frequencies and data rates
for the RF pin.
2.3.7LF[A:B] Pins
The LF[A:B] pins can be used by the LF receiver (LFR) as one differential input channel for sensing low level signals from an
external low frequency (LF) coil. The external LF coil should be connected between the LFA and the LFB pins.
Signaling into the LFR pins can place the FXTH870x6 into various diagnostic or operational modes. The LFR is comprised of the
detector and the decoder.
Each LF[A:B] pin will always have an impedance of approximately 500 k to V
pins are used by the LFR when the LFEN con tro l b it is set and are not functional when the LFEN control bit is clear.
2.3.8PTA[1:0] Pins
The PTA[1:0] pins are general purpose I/O pins. These two pins can be configured as normal bidirectional I/O pins with
programmable pullup or pulldown devices and/or wakeup interrupt capability; or one or both can be connected to the two input
channels of the A/D converter module. The pulldown devices can only be activated if the wakeup interrupt capability is enabled.
User software must configure the general purpose I/O pins so that they do not result in “floating” inputs as described in
Section 6.1. PTA[1:02] map to keyboard Interrupt function bits [1:0].
Sensors
Freescale Semiconductor, Inc.11
due to the LFR input circuitry. The LFA/LFB
SS
FXTH870x6
2.3.9PTA[3:2] Pins
RESET
0.7 V
DD
0.3 V
DD
> 100 nsec
Reset
Initiated
The PTA[3:2] pins are general purpose I/O pin. These two pins can be configured as normal bidirectional I/O pin with
programmable pullup or pulldown devices and/or wakeup interrupt capability; or one or both can be connected to the two input
channels of the Timer Pulse Width (TPM1) module. The pulldown devices can only be activated if the wakeup interrupt capability
is enabled. User software must configure the general purpose I/O pins so that they do not result in “floating” inputs as described
in Section 6.1. PTA[3:2] map to keyboard Interrupt function bits [3:2].
2.3.10BKGD/PTA4 Pin
The BKGD/PTA4 pin is used to place the FXTH870x6 in the BACKGROUND DEBUG mode (BDM) to evaluate MCU code and
to also transfer data to/from the internal memories. If the BKGD/PT A4 pin is held low when the FXTH870x6 comes out of a poweron reset the device will go into the ACTIVE BACKGROUND DEBUG mode (BDM).
The BKGD/PTA4 pin has an internal pullup device and can connected to V
BDM operation after the device as been soldered into the PWB. If in-circuit BDM is desired the BKGD/PTA4 pin can be left
unconnected, but should be connected to VDD through a low impedance resistor (< 10 k) which can be over-driven by an
external signal. This low impedance resistor reduces the possibility of getting into the debug mode in the application due to an
EMC event.
in the application unless there is a need to enter
DD
2.3.11RESET Pin
The RESET pin is used for test and establishing the BDM condition and providing the programming voltage source to the internal
FLASH memory. This pin can also be used to direct to the MCU to the reset vector as described in Section 5.2.
The RESET
operation after the device as been soldered to the PWB. If in-circuit BDM is desired the RESET
should be connected to VDD through a low impedance resistor (< 10 k) which can be over-driven by an external signal. This
low impedance resistor reduces the possibility of getting into the debug mode in the application due to an EMC event.
Activation of the external reset function occurs when the voltage on the RESET pin goes below 0.3 x V
before rising above 0.7 x VDD as shown in Figure 7.
pin has an internal pullup device and can connected to VDD in the application unless there is a need to enter BDM
pin can be left unconnected; but
for at least 100 nsec
DD
Figure 7. RESET Pin Timing
2.3.12PTB[1:0] Pins
The PTB[1:0] pins are general purpose I/O pins. These two pins can be configured as nominal bidirectional I/O pins with
programmable pullup. User software must configure the general purpose I/O pins so that they do not result in “floating” inputs as
described in Section 6.1
FXTH870x6
12Freescale Semiconductor, Inc.
Sensors
3Modes of Operation
The operating modes of the FXTH870x6 are described in this section. Entry into each mode, exit from each mode, and
functionality while in each of the modes are described.
3.1Features
•ACTIVE BACKGROUND DEBUG mode for code development
•STOP modes:
— System clocks stopped
— STOP1: Power down of most internal circuits, including RAM, for maximum power savings; voltage regulator in
standby
— STOP4: All internal circuits powered and full voltage regulation maintained for fastest recovery
3.2RUN Mode
This is the normal operating mode for the FXTH870x6. This mode is selected when the BKGD/PTA4 pin is high at the rising edge
of reset. In this mode, the CPU executes code from internal memory following a reset with execution beginning at address
specified by the reset pseudo-vector ($DFFE and $DFFF).
3.3WAIT Mode
The WAIT mode is also present like other members of the Freescale S08 family members; but is not normally used by the
FXTH870x6 firmware or typical TPMS applications.
3.4ACTIVE BACKGROUND Mode
The ACTIVE BACKGROUND mode functions are managed through the BACKGROUND DEBUG controller (BDC) in the HCS08
core. The BDC provides the means for analyzing MCU operation during software development.
ACTIVE BACKGROUND mode is entered in any of four ways:
•When the BKGD/PTA4 pin is low at the rising edge of a power up reset
•When a BACKGROUND command is received through the BKGD/PTA4 pin
•When a BGND instruction is executed by the CPU
•When encountering a BDC breakpoint
Once in ACTIVE BACKGROUND mode, the CPU is held in a suspended state waiting for serial BACKGROUND commands
rather than executing instructions from the user’s application program. Background commands are of two types:
•Non-intrusive commands, defined as commands that can be issued while the user program is running. Non-intrusive
commands can be issued through the BKGD/PTA4 pin while the MCU is in RUN mode; non-intrusive commands can also
be executed when the MCU is in the ACTIVE BACKGROUND mode. Non-intrusive commands include:
•ACTIVE BACKGROUND commands, which can only be executed while the MCU is in ACTIVE BACKGROUND mode.
ACTIVE BACKGROUND commands include commands to:
— Read or write CPU registers
— Trace one user progra m in stru ct io n at a time
— Leave ACTIVE BACKGROUND mode to return to the user’s application program (GO)
The ACTIVE BACKGROUND mode is used to program a bootloader or user application program into the FLASH program
memory before the MCU is operated in RUN mode for the first time. When the FXTH870x6 is shipped from the Freescale factory,
the FLASH program memory is erased by default (unless specifically requested otherwise) so there is no program that could be
executed in RUN mode until the FLASH memory is initially programmed.
The ACTIVE BACKGROUND mode can also be used to erase and reprogram the FLASH memory after it has been previously
programmed.
FXTH870x6
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Freescale Semiconductor, Inc.13
3.5STOP Modes
One of two stop modes are entered upon execution of a STOP instruction when the STOPE bit in the system option register is
set. In all STOP modes, all internal clocks are halted except for the low frequency 1 kHz oscillator (LFO) which runs continuously
whenever power is applied to the VDD and VSS pins. If the STOPE bit is not set when the CPU executes a STOP instruction, the
MCU will not enter any of the STOP modes and an illegal opcode reset is forced. The STOP modes are selected by setting the
appropriate bits in SPMSC2. Table 1 summarizes the behavior of the MCU in each of the STOP1 and STOP4 modes. The STOP2
mode found in other Freescale S08 family members is not available; but the STOP3 mode is present like other members of the
Freescale S08 family members.
3.5.1STOP1 Mode
The STOP1 mode provides the lowest possible standby power consumption by causing the internal circuitry of the MCU to be
powered down.
When the MCU is in STOP1 mode, all internal circuits that are powered from the voltage regulator are turned off. The voltage
regulator is in a low-power standby state. STOP1 is exited by asserting either a reset or an interrupt function to the MCU.
Entering STOP1 mode automatically asserts LVD. STOP1 cannot be exited until the V
is greater than V
DD
LVDH
or V
LV/DL
rising
(VDD must rise above the LVI re-arm voltage).
Upon wakeup from STOP1 mode, the MCU will start up as from a power-on reset (POR) by taking the reset vector.
NOTE
If there are any pending interrupts that have yet to be serviced then the device will not go
into the STOP1 mode. Be certain that all interrupt flags have been cleared before entry to
STOP1 mode.
3.5.2STOP4 LVD Enabled in STOP Mode
The L VD system is cap able of generating either an interrupt or a reset when the supply voltage drops below the LVD voltage. If
the LVD is enabled by setting the LVDE and the LVDSE bits in SPMSC1 when the CPU executes a STOP instruction, then the
voltage regulator remains active during STOP mode. If the user attempts to enter the STOP1 with the LVD enabled in STOP
(LVDSE = 1), the MCU will enter STOP4 instead.
Table 1. STOP Mode Behavior
ModeSTOP1STOP4
LFO Oscillator, PWUAlways On & Clocking
Real-Time Interrupt (RTI)
MFO Oscillator
HFO OscillatorOffOff
CPUOffStandby
RAMOffStandby
Parameter RegistersOnOn
FLASHOffStandby
TPM1 2-Chan Timer/PWMOffOff
Digital I/ODisabledStandby
Sensor Measurement Interface (SMI)OffOptionally On
Pressure P-cellOffOptionally On
Optional Acceleration g-cellOffOptionally On
Temperature Sensor (in ADC10)OffOptionally On
Normal Temperature RestartOptionally OnOptionally On
Voltage Reference (in ADC10)OffOptionally On
LFR Detector
LFR DecoderOptionally OnOptionally On
RF Controller, Data Buffer, EncoderOptionally OnOptionally On
RF Transmitter
ADC10OffOptionally On
(2)
(4)
(5)
(1)
Optionally OnOptionally On
Periodically OnPeriodically On
Optionally OnOptionally On
Always On if using LFO as Clock
(3)
(3)
(3)
FXTH870x6
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14Freescale Semiconductor, Inc.
Table 1. STOP Mode Behavior (continued)
ModeSTOP1STOP4
RegulatorOffOn
I/O PinsHi-ZStates Held
Wakeup MethodsInterrupts, resetsInterrupts, resets
1. RTI can be used in STOP1 or STOP4 if the clock selected is the LFO. To use the HFO as the clock the MCU must be in the RUN mode.
2. MFO oscillator started if the LFR detectors are periodically sampled, the LFR detectors detect an input signal; a pressure or acceleration
reading is in progress or the RF state machine is sending data.
3. Requires internal ADC10 clock to be enabled.
4. Period of sampling set by MCU.
5. RF data buffer may be set up to run while the CPU is in the STOP modes.
Specific to the tire pressure monitoring application the parameter registers and the LFO with wakeup timer are powered up at all
times whenever voltage is applied to the supply pins. The LFR detector and MFO may be periodically powered up by the LFR
decoder.
3.5.3Active BDM Enabled in STOP Mode
Entry into the ACTIVE BACKGROUND DEBUG mode from RUN mode is enabled if the ENBDM bit in BDCSCR is set. The
BDCSCR register is not memory mapped so it can only be accessed through the BDM interface by use of the BDM commands
READ_STATUS and WRITE_CONTROL. If ENBDM is set when the CPU executes a STOP instruction, the s ystem clocks to the
BACKGROUND DEBUG logic remain active when the MCU enters STOP mode so BACKGROUND DEBUG communication is
still possible. In addition, the voltage regulator does not enter its low-power standby state but maintains full internal regulation. If
the user attempts to enter the STOP1 with ENDBM set, the MCU will instead enter this mode which is STOP4 with system clocks
running.
Most BACKGROUND commands are not available in STOP mode. The memory-access-with-status commands do not allow
memory access, but they report an error indicating that the MCU is in STOP mode. The BACKGROUND command can be used
to wake the MCU from stop and enter ACTIVE BACKGROUND mode if the ENDBM bit is set. Once in BACKGROUND DEBUG
mode, all BACKGROUND commands are available.
3.5.4MCU On-Chip Peripheral Modules in STOP Modes
When the MCU enters any STOP mode, system clocks to the internal peripheral modules except the wakeup timer and LFR
detectors/decoder are stopped. Even in the exception case (ENDBM = 1), where clocks are kept alive to the BACKGROUND
debug logic, clocks to the peripheral systems are halted to reduce power consumption.
I/O Pins
If the MCU is configured to go into STOP1 mode, the I/O pins are forced to their default reset state (Hi-Z) upon entry into stop.
This means that the I/O input and output buffers are turned off and the pullup is disconnected.
Memory
All module interface registers will be reset upon wakeup from STOP1 and the contents of RAM are not preserved. The MCU must
be initialized as upon reset. The contents of the FLASH memory are non-volatile and are preserved in any of the STOP modes.
Parameter Registers
The 64 bytes of parameter registers are kept active in all modes of operation as long as power is applied to the supply pins. The
contents of the parameter registers behave like RAM and are unaffected by any reset.
LFO
The LFO remains active regardless of any mode of operation.
MFO
The medium frequency oscillator (MFO) will remain powered up when the MCU enters the STOP mode only when the SMI has
been initiated to make a pressure or acceleration measurement; or when the RF transmitter’s state machine is processing data.
HFO
The HFO is halted in all STOP modes.
PWU
The PWU remains active regardless of any mode of operation.
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ADC10
The internal asynchronous ADC10 clock is always used as the conversion clock. The ADC10 can continue operation during
STOP4 mode. Conversions can be initiated while the MCU is the STOP4 mode. All ADC10 module registers contain their reset
values following exit from STOP1 mode.
LFR
When the MCU enters STOP mode the detectors in the LFR will remain powered up depending on the states of the bits selecting
the periodic sampling. Refer to Section 12 for more details.
Bandgap Reference
The bandgap reference is enabled whenever the sensor measurement interface requires sensor or voltage measurements.
TPM1
When the MCU enters STOP mode, the clock to the TPM1 module stops and the module halts operation. If the MCU is configured
to go into STOP1 mode, the TPM1 module will be reset upon wakeup from STOP and must be re-initialized.
Voltage Regulator
The voltage regulator enters a low-power standby state when the MCU enters any of the STOP modes except STOP4 (LVDSE
= 1 or ENBDM = 1).
Temperature Sensor
The temperature sensor is powered up on command from the MCU.
Temperature Restart
When the MCU enters a STOP mode the temperature restart will remain powered up if the TRE bit is set. If the temperature restart
level is reached the MCU will restart from the reset vector.
3.5.5RFM Module in STOP Modes
The RFM’s external crystal oscillator (XCO), bit rate generator, PLL, VCO, RF data buffer , data encoder , and RF output stage will
remain powered up in STOP modes during a transmission, or if the SEND bit has been set and DIRECT mode has been enabled.
RF Output
When the RFM finishes a transmission sequence the external crystal oscillator (XCO), bit rate generator, PLL, VCO, RF data
buffer, data encoder, and RF output stage will remain powered up if the SEND bit is set.
3.5.6P-cell in STOP Modes
The P-cell is powered up only during a measurement if scheduled by the sensor measurement interface. Otherwise it is powered
down.
3.5.7Optional g-Cell in STOP Modes
The g-cell is powered up only during a measurement if scheduled by the sensor measurement interface. Otherwise it is powered
down.
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4Memory
$0000
$004F
$0050
$008F
$1800
$17FF
$182B
$182C
$FFFF
$0090
$C000
$BFFF
DIRECT PAGE REGISTERS
RAM 512 BYTES
UNIMPLEMENTED
HIGH PAGE REGISTERS
5488 BYTES
41964 BYTES
$028F
$0290
PARAMETER REGISTERS
$DFC0
$DFBF
USER FLASH
8128 BYTES
USER VECTORS
FIRMWARE FLASH
8128 BYTES
$E000
$DFFF
$E040
$E03F
FIRMWARE JUMP TABLE
The overall memory map of the FXTH870x6 resides on the MCU.
4.1MCU Memory Map
As shown in Figure 8, MCU on-chip memory in the FXTH870x6 consists of parameter registers, RAM, FLASH program memory
for nonvolatile data storage, and I/O and control/status registers. The registers are divided into four groups:
•Direct-page registers ($0000 through $004F)
•Parameter registers ($0050 through $008F)
•RAM ($0090 through $028F)
•High-page registers ($1800 through $182B)
Figure 8. FXTH870x6 MCU Memory Map
The total programmable FLASH memory map is 16K, but the upper 8K is used for firmware and test software. Upon power up
the firmware will initialize the device and redirect all vectors to the user area from $DFC0 through $DFFF . Any calls to the firmware
subroutines are accessed through a jump table starting at location $E000 (see Section 14).
4.2Reset and Interrupt Vectors
Table 2 shows address assignments for jump table to the reset and interrupt vectors. The vector names shown in this table are
the labels used in the equate file provided by Freescale in the CodeWarrior project file.
The registers in the FXTH870x6 are divided into these four groups:
•Direct-page registers are located in the first 80 locations in the memory map; these are accessible with efficient direct
addressing mode instructions.
•The parameter registers begin at address $0050; these are also accessible with efficient direct addressing mode
instructions.
•High-page registers are used less often, so they are located above $1800 in the memory map. This leaves more room in the
direct page for more frequently used registers and variables.
•The nonvolatile register area consists of a block of 16 locations in FLASH memory at $FFB0:FFBF. Nonvolatile register
locations include:
— Three values that are loaded into working registers at reset
— An 8-byte back door comparison key that optionally allows the user to gain controlled access to secure memory.
Because the nonvolatile register locations are FLASH memory, they must be erased and programmed like other FLASH memory
locations.
Direct page registers are located within the first 256 locations in the memory map, so they are accessible with efficient direct
addressing mode instructions, which requires only the lower byte of the address. Bit manipulation instructions can be used to
access any bit in any direct-page register. Table 3 is a summary of all user-accessible direct-page registers and control bits.
Those related to the TPMS application and modules are described in detail in this specification.
The register names in column two of the following tables are shown in bold to set them apart from the bit names to the right. Cells
that are not associated with named bits are shaded. A shaded cell with a 0 indicates this unused bit always reads as a 0. Shaded
cells with dashes indicate unused or reserved bit locations that could read as 1s or 0s.
$0020LFCTL1LFENSRESCARMODLPAGEIDSEL[1:0]SENS[1:0]
$0021LFCTRLE
$0022LFCTRLDAVFOF[1:0}DEQSAZDC[1:0]ONMODECHK125[1:0]
$0023LFCTRLCAMPGAIN[1:0]FINSEL[1:0]AZENLOWQ[1:0]DEQEN
$0024LFCTRLBHYST[1:0]LFFAFLFCAFLFPOLLFCPTAZ[2:0]
$0025LFCTRLATESTSEL[3:0]LFCC[3:0]
$0026Reserved
$0027Reserved
Note: Shaded bits are recommended to only be controlled by firmware or factory test.
Note: Shaded bits are recommended to only be controlled by firmware or factory test.
IFPDISPCIFIDFNUM[3:0]
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Table 7. RFM Register Summary - RPAGE = 1
AddressRegister NameBit 7654321Bit 0
$0030RFCR0BPS[7:0]
$0031RFCR1FRM[7:0]
$0032RFCR2SENDRPAGEEOMPWR[4:0]
$0033RFCR3DATA
$0034RFCR4RFBT[7:0]
$0035RFCR5BOOSTLFSR[6:0]
$0036RFCR6VCO_GAIN[1:0]RFFT[5:0]
$0037RFCR7RFIFRFEFRFVFRFIAKRFIENRFLVDENRCTSRFMRST
$0038EPR—/VCD3PLL_LPF_[2:0]/VCD[2:0]
$0039Reserved
$003AReserved
$003BReserved
$003CRFD0RFD[135:128]
$003DRFD1RFD[143:136]
$003ERFD2RFD[151:144]
$003FRFD3RFD[159:152]
$0040RFD4RFD[167:160]
$0041RFD5RFD[175:168]
$0042RFD6RFD[183:176]
$0043RFD7RFD[191:184]
$0044RFD8RFD[199:192]
$0045RFD9RFD[207:200]
$0046RFD10RFD[215:208]
$0047RFD11RFD[223:216]
$0048RFD12RFD[231:224]
$0049RFD13RFD[239:232]
$004ARFD14RFD[247:240]
$004BRFD15RFD[255:248]
$004CReserved
$004DReserved
$004EReserved
$004FReserved
Note: Shaded bits are recommended to only be controlled by firmware or factory test.
IFPDISPCIFIDFNUM[3:0]
PA_SLOPEVCD_EN
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4.4High Address Registers
High-page registers are used much less often, so they are located above $1800 in the memory map. This leaves more room in
the direct page for more frequently used registers and variables. The registers control system level features as given in Table 8.
Note: Reserved bits shown as 0 must always be written to 0.
Reserved bits shown as 1 must always be written to 1.
Shaded bits are recommended to only be controlled by firmware or factory test.
0000000BDFR
0COPT[2:0]LFOSELTCLKDIVBUSCLKS[1:0]
0RTIS{2:0]
0BGBE
000PDF0PPDACKPDC0
KBFIRQFTRFPWUFLFFRFF
TRH[2:0]TRO
0000SEC0[1:0}
0FBLANK00
0
1
4.5MCU Parameter Registers
The 64 bytes of parameter registers are located at addresses $0050 through $008F. These registers are powered up at all times
and may be used to store temporary or history data during the times that the MCU is in any of the STOP modes. The parameter
register at $008F is used by the firmware for interrupt flags.
4.6MCU RAM
The FXTH870x6 includes static RAM. The locations in RAM below $0100 can be accessed using the more efficient direct
addressing mode, and any single bit in this area can be accessed with the bit-manipulation instructions (BCLR, BSET, BRCLR,
and BRSET). Locating the most frequently accessed program variables in this area of RAM is preferred.
The RAM retains data when the MCU is in low-power WAIT, STOP3 or ST OP4 modes. At power-on or after wakeup from STOP1,
the contents of RAM are not initialized. RAM data is unaffected by any reset provided that the supply voltage does not drop below
the minimum value for RAM retention (V
When security is enabled, the RAM is considered a secure memory resource and is not accessible through BDM or through code
executing from non-secure memory. See Section 4.8 for a detailed description of the security feature.
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22Freescale Semiconductor, Inc.
RAM).
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None of the RAM locations are used directly by the firmware provided by Freescale. The firmware routines utilize RAM only
through stack operations; and the user needs to be aware of stack depth required by each routine as described in the
CodeWarrior project files supplied by Freescale.
4.7FLASH
The FLASH memory is intended primarily for program storage. The operating program can be loaded into the FLASH memory
after final assembly of the application product using the single-wire BACKGROUND DEBUG interface. Because no speci al
voltages are needed for FLASH erase and programming operations, in-application programming is also possible through other
software-controlled communication paths. For a more detailed discussion of in-circuit and in-application programming, refer to
the HCS08 Family Reference Manual, Volume I, Freescale document order number HCS08RMV1/D.
4.7.1Features
Features of the FLASH memory include:
•User Program FLASH Size — 8192 bytes (16 pages of 512 bytes each)
•Single power supply program and erase
•Command interface for fast program and erase operation
•Up to 100,000 program/erase cycles at typical voltage and temperature
•Flexible block protection
•Security feature for FLASH and RAM
•Auto power-down for low-frequency read accesses
4.7.2Program and Erase Times
Before any program or erase command can be accepted, the FLASH clock divider register (FCDIV) must be written to set the
internal clock for the FLASH module to a frequency (f
so normally this write is performed during reset initialization. FCDIV cannot be written if the access error flag, FACCERR in
FSTAT, is set. The user must ensure that FACCERR is not set before writing to the FCDIV register. One period of the resulting
clock (1/f
) is used by the command processor to time program and erase pulses. An integer number of these timing pulses
FCLK
are used by the command processor to complete a program or erase command.
) between 150 kHz and 200 kHz. This register can be written only once,
FCLK
Table 9 shows program and erase times. The bus clock frequency and FCDIV determine the frequency of FCLK (f
for one cycle of FCLK is t
case where t
=5s. Program and erase times shown include overhead for the command state machine and enabling and
FCLK
FCLK
=1/f
. The times are shown as a number of cycles of FCLK and as an absolute time for the
FCLK
FCLK
). The time
disabling of program and erase voltages.
Table 9. Program and Erase Times
ParameterCycles of FCLKTime if FCLK = 200 kHz
Byte program 945 s
Byte program (burst) 420 s
Page erase 400020 ms
Mass erase 20,000100 ms
1. Excluding start/end overhead
(1)
4.7.3Program and Erase Command Execution
The steps for executing any of the commands are listed below. The FCDIV register must be initialized and any error flags cleared
before beginning command execution. The command execution steps are:
1.Write a data value to an address in the FLASH array. The address and data information from this write is latched into
the FLASH interface. This write is a required first step in any command sequence. For erase and blank check
commands, the value of the data is not important. For page erase commands, the address may be any address in the
512-byte page of FLASH to be erased. For mass erase and blank check commands, the address can be any address
in the FLASH memory. Whole pages of 512 bytes are the smallest block of FLASH that may be erased.
Do not program any byte in the FLASH more than once after a successful erase operation. Reprogramming bits to a
byte which is already programmed is not allowed without first erasing the page in which the byte resides or mass
erasing the entire FLASH memory. Programming without first erasing may disturb data stored in the FLASH.
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2.Write the command code for the desired command to FCMD. The five valid commands are blank check (0x05), byte
program (0x20), burst program (0x25), page erase (0x40), and mass erase (0x41). The command code is latched into
the command buffer.
3.Write a 1 to the FCBEF bit in FSTAT to clear FCBEF and launch the command (including its address and data
information).
A partial command sequence can be aborted manually by writing a 0 to FCBEF any time after the write to the memory array and
before writing the 1 that clears FCBEF and launches the complete command. Aborting a command in this way sets the FACCERR
access error flag which must be cleared before starting a new command.
A strictly monitored procedure must be obeyed or the command will not be accepted. This minimizes the possibility of any
unintended changes to the FLASH memory contents. The command complete flag (FCCF) indicates when a command is
complete. The command sequence must be completed by clearing FCBEF to launch the command. Figure 9 is a flowchart for
executing all of the commands except for burst programming. The FCDIV register must be initialized before using any FLASH
commands. This must be done only once following a reset.
4.7.4Burst Program Execution
The burst program command is used to program sequential bytes of data in less time than would be required using the standard
program command. This is possible because the high voltage to the FLASH array does not need to be disabled between program
operations. Ordinarily, when a program or erase command is issued, an internal charge pump associated with the FLASH
memory must be enabled to supply high voltage to the array. Upon completion of the command, the charge pump is turned off.
When a burst program command is issued, the charge pump is enabled and then remains enabled after completion of the burst
program operation if these two conditions are met:
•The next burst program command has been queued before the current program operation has completed.
•The next sequential address selects a byte on the same physical row as the current byte being programmed. A row of FLASH
memory consists of 64 bytes. A byte within a row is selected by addresses A5 through A0. A new row begins when addresses
A5 through A0 are all zero.
The first byte of a series of sequential bytes being programmed in burst mode will take the same amount of time to program as
a byte programmed in standard mode. Subsequent bytes will program in the burst program time provided that the conditions
above are met. In the case the next sequential address is the beginning of a new row, the program time for that byte will be the
standard time instead of the burst time. This is because the high voltage to the array must be disabled and then enabled again.
If a new burst command has not been queued before the current command completes, then the charge pump will be disabled
and high voltage removed from the array.
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START
WRITE TO FLASH
TO BUFFER ADDRESS AND DATA
WRITE COMMAND TO FCMD
NO
YES
FPVIOL OR
WRITE 1 TO FCBEF
TO LAUNCH COMMAND
AND CLEAR FCBEF
(2)
1
0
FCCF?
ERROR EXIT
DONE
Note 2: Wait at least four bus cycles
0
FACCERR?
CLEAR ERROR
FACCERR?
WRITE TO FCDIV
(1)
Note 1: Required only once after reset.
1
before checking FCBEF or FCCF.
FLASH PROGRAM AND
ERASE FLOW
Figure 9. FLASH Program and Erase Flowchart
Programming time for the FLASH through the BDM function is dependent on the specific external BDM interface tool and
software being used. Consult tool vendor for programming times.
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FXTH870x6
1
0
FCBEF?
START
WRITE TO FLASH
TO BUFFER ADDRESS AND DATA
WRITE COMMAND ($25) TO FCMD
NO
YES
FPVIO OR
WRITE 1 TO FCBEF
TO LAUNCH COMMAND
AND CLEAR FCBEF
(2)
NO
YES
NEW BURST COMMAND?
1
0
FCCF?
ERROR EXIT
DONE
Note 2: Wait at least four bus cycles before
1
0
FACCERR?
CLEAR ERROR
FACCERR?
Note 1: Required only once after reset.
WRITE TO FCDIV
(1)
checking FCBEF or FCCF.
FLASH BURST
PROGRAM FLOW
4.7.5Access Errors
An access error occurs whenever the command execution protocol is violated.
Any of the following specific actions will cause the access error flag (FACCERR) in FSTAT to be set. FACCERR must be cleared
Figure 10. FLASH Burst Program Flowchart
by writing a 1 to FACCERR in FSTAT before any command can be processed.
•Writing to a FLASH address before the internal FLASH clock frequency has been set by writing to the FCDIV register
• Writing to a FLASH address while FCBEF is not set (A new command cannot be started until the command buffer is empty.)
•Writing a second time to a FLASH address before launching the previous command (There is only one write to FLASH for
every command.)
•Writing a second time to FCMD before launching the previous command (There is only one write to FCMD for every
command.)
•Writing to any FLASH control register other than FCMD after writing to a FLASH address
•Writing any command code other than the five allowed codes (0x05, 0x20, 0x25, 0x40, or 0x41) to FCMD
•Accessing (read or write) any FLASH control register other than the write to FSTAT (to clear FCBEF and launch the
command) after writing the command to FCMD.
•The MCU enters STOP mode while a program or erase command is in progress (The command is aborted.)
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