Processor Users Manual

29-90 MPC8260 PowerQUICC II UserÕs Manual MOTOROLA
Part IV. Communications Processor Module
See also Section 29.16.1, ÒUsing Transmit Internal Rate Mode.Ó
29.14 ATM Transmit Command
The CPM command set includes an ATM TRANSMIT that can be sent to the CP command
register (CPCR), described in Section 13.4.1.
The
ATM TRANSMIT command (CPCR[opcode] = 0b1010, CPCR[SBC[code]] = 0b01110,
CPCR[SBC[page]] = 0b00100 or 0b00101 (FCC1 or FCC2), CPCR[MCN] =
0b0000_1010) turns a passive channel into an active channel by inserting it into the APC
scheduling table. Note that an
ATM TRANSMIT command should be issued only after the
channelÕs TCT is completely initialized and the channel has BDs ready to transmit. Note
also that CPCR[SBC[code]] = 0b01110 and not FCC1 or FCC2 code.
Before issuing the command, the user should initialize COMM_INFO Þelds in the
parameter RAM as described in Figure 29-63.
Table 29-50 describes COMM_INFO Þelds
Offset 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
0x86 Ñ CTB PHY# ACT PRI
0x88 Channel Code (CC)
0x8A BT
Figure 29-63. COMM_INFO Field
Table 29-50. COMM_INFO Field Descriptions
Offset Bits Name Description
0x86 0Ð4 Ñ Reserved, should be cleared.
5 CTB Connection tables bus. Used for external channels only
0 External connection tables reside on the 60x bus.
1 External connection tables reside on the local bus.
6Ð10 PHY# PHY number. In single PHY mode this Þeld should be cleared In multiple PHY mode this
Þeld is an index to the APC parameter table associated with this channel.
11Ð12 ACT ATM channel type
00 Other channel
01 VBR channel
1x Reserved
13-15 PRI APC priority level.
000Ñhighest priority (APC_LEVEL1), 111Ñlowest priority (APC_LEVEL8).
0x88 0-15 CC Channel code. The channel code associated with the current channel.
0x8A 0-15 BT Burst tolerance. For use by VBR channels only (ACT Þeld is 0b01). SpeciÞes the initial burst
tolerance (GCRA burst credit) of the current VC.