Freescale Semiconductor MPC8260 - Manual (Page 849)

MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor 28-1
Chapter 28
Multi-Channel Controllers (MCCs)
NOTE
The MPC8250 and the MPC8255 have only one MCC.
The signalling system #7 (SS7) functionality described in this chapter is not
available on rev A.1 .29
µm (HiP3) silicon.
Refer to www.freescale.com for the latest RAM microcode packages that
support enhancements.
A multi-channel controller (MCC) allows the PowerQUICC II to support up to 128 separate time-division
serial channels on one peripheral. The PowerQUICC II has two MCCs. Each MCC is paired with a serial
interface (SI), allowing the MCC to communicate over any of that SI’s 4 time-division multiplexed streams
(TDM).
An MCC’s channels are assigned to a particular TDM in subgroups of 32 channels. MCC1’s channels
(0-127) may not be programmed to work with SI2, nor MCC2’s channels (128-255) to work with SI1. Each
channel of an MCC can be programmed to perform in a mode separate from the other channels of that
MCC.
Proper programming of the SI and SIRAM is responsible for the routing of timeslots within a TDM stream
to the appropriate MCC channel at the desired time. Programming the SI is covered in
Chapter 15, “Serial
Interface with Time-Slot Assigner.” Users should be familiar with the information there before
proceeding.
Each MCC has the following features:
• Up to 128 independent HDLC or transparent communication channels or up to 64 SS7 channels
• Independent mapping for receive/transmit
• Supports HDLC, transparent, or SS7 protocols on a per-channel basis
• Supports additional circuit emulation service functionality when used in conjunction with ATM
AAL1
• Supports interworking with AAL0
• Up to 256 DMA channels with independent buffer descriptor (BD) tables
• Five interrupt circular tables with programmable size and overflow identification. One for transmit
and four for receive.
• Global loop mode
• Individual channel loop mode
• Efficient bus usage (no bus usage for inactive channel or for active channels with nothing to
transmit)