I don't know linux very well how do I setup SCC3 and SCC4 to give out a baud rate of 128000 and 256000 bits per second respectively. I'm using a MPC860, the function i'm using is:
int __init rs_8xx_init(void)
How do I program values into BRG, and connect to the channels. Then set up the I/O(program the ports as outputs, initialize values). Change SCC RS232-->RS485 mode. ASYNC-->SYNC

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