TIMER A
7.6 Pulse width modulation (PWM) mode
7.6.2 Trigger
When a trigger is generated, the TAiOUT pin starts to output PWM pulses. An internal or an external trigger
can be selected as that trigger.
An internal trigger is selected when the trigger select bits (bits 4 and 3 at addresses 5616 to 5A16, D616 to
DA16) are “00
2
” or “01
2
”; an external trigger is selected when these bits are “10
2
” or “11 .”
2
A trigger generated during PWM pulse output is invalid, and it does not affect the pulse output operation.
(1) When selecting internal trigger
A trigger is generated when “1” is written to the count start bit (addresses 4016, 4116).
(2) When selecting external trigger
A trigger is generated at the falling edge of the TAiIN pin’s input signal when bit 3 at addresses
5616 to 5A16, D616 to DA16 is “0,” or at its rising edge when bit 3 is “1.” However, the trigger input is
acceptableonly when the count start bit is “1.”
When using an external trigger, set the port P6, port P2, and port P4 direction registers’ bits which
correspond to the TAiIN pins for the input mode.
7905 Group User’s Manual Rev.1.0
7-43
RENESAS [ RENESAS TECHNOLOGY CORP ]
