2 command register example, 3 command execution latency, 5 dual-port ram – Freescale Semiconductor MPC8260 User Manual

Page 565: Command register example -17, Command execution latency -17, Dual-port ram -17

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Communications Processor Module Overview

MPC8260 PowerQUICC II Family Reference Manual, Rev. 2

Freescale Semiconductor

14-17

14.4.2

Command Register Example

To perform a complete reset of the CP, the value 0x8001_0000 should be written to the CPCR. Following
this command, the CPCR returns the value 0x0000_0000 after two clocks.

14.4.3

Command Execution Latency

The worst-case command execution latency is 200 clocks and the typical command execution latency is
about 40 clocks.

14.5

Dual-Port RAM

The CPM static RAM (24 Kbyte on 0.29µm (HiP3) devices and 32 Kbyte on 0.25µm (HiP4) devices) is
shown in

Figure 14-7

.

SET

GROUP

ADDRESS

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

GCI

ABORT

REQUEST

GCI abort request. The GCI receiver sends an abort request on the E-bit.

GCI

TIMEOUT

GCI time-out. The GCI performs the timeout function.

RESET

BCS

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

MCC

STOP

TRANSMIT

See

Section 28.7, “MCC Commands

.”

MCC

STOP

RECEIVE

See

Section 28.7, “MCC Commands

.”

MCC

RESET

1

MCC reset. Provides a hard reset to the MCC FIFOs. See

Section 28.7, “MCC Commands

.” To use

this command, software should execute the following sequence:
1 Disable the TDM by clearing the appropriate enable bit in SIxGMR[4-7] (See Table 14-4,

“SIxGMR Field Descriptions.”).

2 Issue the MCC RSET command.
3 Issue the INIT RX AND TX command.
4 Reprogram the specific MCC channel, global parameters, and any BDs that need to be updated.
5 Set the appropriate enable bit in SIxGMR[4-7]. (See Table 14-4, “SIxGMR Field Descriptions.”).

ATM

TRANSMIT

2

See

Section 30.14, “ATM Transmit Command

.”

RANDOM

NUMBER

Generate a random number and put it in dual-port RAM; see RAND in Table 14-10.

1

Not available on .29

µm (HiP3) Rev A.1 devices.

2

Not available on the MPC8250.

Table 14-8. Command Descriptions (continued)

Command

Description

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