I dig deep into the board of 98 pcm and found it has 243 ohm resistor, vs 909 ohm on the 94 board. They are of similar size and likely 0.75w. Everthing else is aranged identical with 10k isolation.
The 98 pcm uses the newer style sender with 50-250 ohm sender, and with that resistor it goes upto to 2.5v. I will have to live up with 0-90 ohm, the low resolution and do some interpolation.
Also test the pwm channel at pin b5 with mode 4 command. It will work perfect for my application.
The output register of pin b5 is located at word_106c on eside. I wonder about the first byte of the pwm register, the second is the duty cycle, so I guess the first will be frequency. Any ideas how to manipulate it and what are the limits.
When I am done with this will test some 64kb chips. Pin a15 on the t flash chips is grounded. Is the corresponding pin on the processor connected to something or is left open? First I will test with pin left open. Than if it doesn`t work I will try to destroy the board with some solder work.
Xnke, You have great fabriaction skills. That headers look so sweet. How much is the estimate for the power output?