FXTH87xx11 and FXTH87xx12 Embedded Firmware User Guide, Rev. 2.1
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Freescale Semiconductor, Inc.
Firmware Functions
•
Returns
:
— UINT8 u8Status: Valid error flags/outputs are described in
3.2.15
UINT8 TPMS_READ_DYNAMIC_ACCEL_XZ(UINT8 u8Filter, UINT8*
u8OffsetX, UINT8* u8OffsetZ, UINT16* u16UUMA)
•
Description:
This function automatically executes a TPMS_READ_DYNAMIC_ACCEL_X
measurement, followed by a TPMS_READ_DYNAMIC_ACCEL_Z measurement with given
initial dynamic offsets. Refer to the description of these functions for more information.
•
Stack size:
60 bytes
•
Approx. Duration:
50240 usec from one extreme to the center; 8200 usec best case.
•
Power Management:
This function requires the core to be configured for STOP4 mode and
running at full bus speed.
•
Interrupt Management:
This function utilizes the ADC interrupt to wake-up from STOP mode.
•
Resources:
SMI, ADC, internal bond wires.
•
Input Parameters:
— UINT8 u8FiltSelect: If non-zero, 250-Hz filter enabled. Otherwise, 500-Hz filter selected.
Table 19. Valid output conditions for TPMS_READ_ACCELERATION_XZ
u8Status Value
Measurement Value
Condition
$08
$03FF
Uncompensated X acceleration reading outside of valid range (high).
$08
$0000
Uncompensated X acceleration reading outside of valid range (low).
$28
$03FF
Uncompensated X acceleration reading outside of valid range (high), and LVWF
set.
$28
$0000
Uncompensated X acceleration reading outside of valid range (low,) and LVWF
set.
$10
$03FF
Uncompensated Z acceleration reading outside of valid range (high).
$10
$0000
Uncompensated Z acceleration reading outside of valid range (low).
$30
$03FF
Uncompensated Z acceleration reading outside of valid range (high), and LVWF
set.
$30
$0000
Uncompensated Z acceleration reading outside of valid range (low), and LVWF
set.
$18
$03FF
Uncompensated X and Z acceleration readings outside of valid range (high).
$18
$0000
Uncompensated X and Z acceleration readings outside of valid range (low).
$38
$03FF
Uncompensated X and Z acceleration readings outside of valid range (high), and
LVWF set.
$38
$0000
Uncompensated X and Z acceleration readings outside of valid range (low), and
LVWF set.
$80
Undefined
Uncompensated acceleration reading not acquired.
$A0
Undefined
Uncompensated acceleration reading not acquired, and LVWF set.
$00
Between $0001 - $03FE
Valid uncompensated acceleration reading.
$20
Between $0001 - $03FE
Valid uncompensated acceleration reading, but LVWF set.
