MC68HC908MR8 Datasheet, PDF (167/372 Pages) Motorola, Inc – Microcontrollers

Pulse-Width Modulator for Motor Control (PWMMC)
Fault Protection
9.7.1.3 Manual Mode
In manual mode, the PWM(s) are disabled immediately once a filtered
fault condition is detected (logic high). The PWM(s) remain disabled until
software clears the corresponding FFLAGx event bit and a new PWM
cycle begins. In manual mode, the fault pins are grouped in pairs, each
pair sharing common functionality. A fault condition on fault 1 may be
cleared, allowing the PWM(s) to enable at the start of a PWM cycle
regardless of the logic level at the fault pin. See Figure 9-25. A fault
condition on fault 4 can be cleared, allowing the PWM(s) to enable, only
if a logic low level at the fault pin is present at the start of a PWM cycle.
See Figure 9-26.
FILTERED FAULT PIN 1
PWM(S) ENABLED
PWM(S) DISABLED
PWM(S) ENABLED
FFLAGx CLEARED
Figure 9-25. PWM Disabling in Manual Mode (Example 1)
FILTERED FAULT PIN 4
PWM(S) ENABLED
PWM(S) DISABLED
PWM(S) ENABLED
FFLAGx CLEARED
Figure 9-26. PWM Disabling in Manual Mode (Example 2)
MC68HC908MR8 — Rev 4.1
Freescale Semiconductor Pulse-Width Modulator for Motor Control (PWMMC)
Technical Data
167