Freescale Semiconductor PowerQUICC MPC885 Reference Manual page 576

Powerquicc family

Table of Contents

Communications Processor

Restart transmission. After

begins polling the R bit of the current BD.

Closes the current RxBD in mid-reception; reception continues using the next available BD. Use

Initialize IDMA transfers. Initializes the IDMA internal CP state to the user-defined reset value.

Stop IDMA transfers. The CP terminates current IDMA transfers.

Used to activate, deactivate, or reconfigure the 16 timers of the RISC timer table.

Sets a hash table bit for the Ethernet logical group address recognition function.

GCI receiver sends an abort request.

Performs the GCI timeout function.

Used in BISYNC mode to reset the block check sequence calculation.

Section 39.4, "Port-to-Port (PTP) Switching."

USB command code. The specific USB commands are described in

Undefined. Reserved for use by Freescale-supplied RAM microcode packages.

CP Command Examples

To completely reset the CPM, write 0x8001 to the CPCR. After the FLG bit has cleared, setup of the CPM

can continue. To execute

command is executing, the CPCR returns a 0x0341 value; after executing, it returns 0x0340.

CP Command Execution Latency

The worst-case command execution latency for the CP is 500 clocks, while the typical command execution

latency is about 40 clocks.

Dual-Port RAM

The CPM has 8 Kbytes of static RAM configured as dual-port memory, shown in

The entire dual-port RAM should be cleared as the first step in system

initialization. This step should be followed by issuing a CPM reset using the

CPCR. Only after these two steps should the dual-port RAM be

programmed for specific CPM functions.

Table 18-8. CP Commands (continued)

to access the data buffer without waiting for the SCC to finish filling it.

on SCC2, for example, write 0x0341 to the CPCR. While the

ENTER HUNT MODE

MPC885 PowerQUICC Family Reference Manual, Rev. 2

GRACEFUL STOP TX

starts the transmitter, which

Section 31.13, "USB CP

Freescale Semiconductor