I see also no reason, why the 8051 should not can do the job.

If I understand it right, there is no protocoll overhead on DMX512. Any received byte was stored as reload value of the selected channel.

And also a 12 channel PWM consume only 12 * 3 + 6 = 42 cycle of the timer interrupt.
E.g. on the T89C51RD2 at 20MHz the timer interrupt was called every 20Mhz / 6 / 256 / 100Hz = 130 cycle. So still many time left to handle the DMX512 receive.

Additional the first 5 channels can be realized with the PCA and then no CPU time was needed for these, only for the remaining 7 channels: 7 * 3 + 6 = 27 cycle.



Peter