Freescale Semiconductor MPC8260 - Manual (Page 812)

SCC AppleTalk Mode
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
26-4 Freescale Semiconductor
8. Clear TINV and RINV so data will not be inverted.
9. Set TSNC to 1.5 bit times (0b10).
10. Clear EDGE. Both the positive and negative edges are used to change the sample point (default).
11. Clear RTSM (default).
12. Set all other bits to zero or default.
13. Set ENT and ENR as the last step to begin operation.
26.4.2 Programming the PSMR
Follow these steps to program the protocol-specific mode register:
1. Set NOF to 0b0001 giving two flags before frames (one opening flag, plus one additional flag).
2. Set CRC 16-bit CRC-CCITT.
3. Set DRT.
4. Set all other bits to zero or default.
For the PSMR definition, see Section 22.8, “HDLC Mode Register (PSMR).”
26.4.3 Programming the TODR
Use the transmit-on-demand (TODR) register to expedite a transmit frame. See Section 20.1.4,
“Transmit-on-Demand Register (TODR).”
26.4.4 SCC AppleTalk Programming Example
Except for the previously discussed register programming, use the example in Section 22.15.6, “HDLC
Bus Protocol Programming.”