Firmware Functions
FXTH87xx11 and FXTH87xx12 Embedded Firmware User Guide, Rev. 2.1
Freescale Semiconductor, Inc.
39
3.2.40
UINT8 TPMS_WIRE_AND_ADC_CHECK(UINT8 u8TestMask)
•
Description:
This function will check if there is any bonding wire failure between the embedded
core and the P-cell; or between the core and the g-cell. It will also perform an optional a g-cell
self-test, and/or an ADC test. The latter will consist on taking two reference measurements (ground
and Vdd) using internal channels and comparing them with the expected results. The optional
g-cell self-test sends a self-test signal and verifies that the g-cell deflects as expected. It can only
be called when the device is in
parking
or
static
mode. When configuring for a P-cell or g-cell wire
check, Interrupts must be enabled before calling this routine. In case of no issues found, “0” will
be returned, else it will set status flags as follows:
— On P-cell wire-bond error, sets “pressure error” flag.
— On g-cell wire-bond or Self-Test error, sets “acceleration error” flag.
— On ADC error, sets the “ADCERR” flag.
•
Stack size:
36 bytes
•
Approx. Duration:
14,926 usec (all checks), 106 usec (ADC only), 3,089 usec (P-cell only),
3,087 usec (X-Axis l wire-bond only), 3,089 usec (Z-Axis 1 wire-bond only), 5622 usec (g-cell
Self-Test only).
•
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:
ADC, SMI, internal bond wires.
•
Input Parameters:
— UINT8 u8TestMask: This variable determines what checks are performed as described by
.
•
Returns
:
— UINT8 u8Status: Status flags as described in
.
Table 27. u8TestMask format
u8TestMask Bit
Description
BIT0
Reserved.
BIT1
If set, g-cell Self-test performed. Refer to warning below.
BIT2
If set, P-cell bond-wire check performed.
BIT3
If set, X-axis bond-wire check performed.
BIT4
If set, Z-axis bond-wire check performed.
BIT5:6
Reserved.
BIT7
If set, ADC check performed.
