topic Re: Issues with Timer Module, Pulse Accumulator B set to Event Counter Mode - MC9S12DP256B in S12 / MagniV Microcontrollers

Issues with Timer Module, Pulse Accumulator B set to Event Counter Mode - MC9S12DP256B

admin — Tue, 30 Dec 2008 10:23:26 GMT

Hello,

I am using MC9S12DP256B. I am trying to get Pulse Accumulator A and Pulse Accumulator B working in Event Counter Mode for both A and B. I have function Generator connected to ICO0 and ICO7. Timer Registers are all default except: PACTL = 40h and PBCTL = 40h. Pulse Accumulator A works fine with this setup but Pulse Accumulator B is not counting pulses. I am not sure what I am doing wrong.

Also I am using Code Warrior, with what command would I be able to read PACN3 and PACN2 in one clock cycle.

Thanks for all the help and Happy New Year everybody.

Ulan

Re: Issues with Timer Module, Pulse Accumulator B set to Event Counter Mode - MC9S12DP256B

kef — Tue, 30 Dec 2008 16:40:31 GMT

Pulse accumulators A and B are not the same. PACTL register has edge and mode select bits, while PBCTL doesn't have edge select bits. Active edge for accumulator B is selected the same as input capture edge for channel 0. So you should also set up TCTL4 register. According to ECT_16B8C Block User Guide V01.06, pulse accumulator B (like pulse accumulator A) is also independent from timer enable bit (TEN).

I don't know why do you want to access PACN3 and PACN2 in the same cycle. Pulse accumulator B uses concatenated 16bits register PACN1ACN0.

Try writing help and hit enter in CW command window. DW command seems to be what you need.