Intel NETWORK PROCESSOR IXP2800 - Manual (Page 315)

Hardware Reference Manual 315
Intel
®
IXP2800 Network Processor
Media and Switch Fabric Interface
8.9.6.2 Training Transmitter State Machine
The Training State Machine makes state transitions on each bus transfer of 16 bits, as described in
Table 115 .
8.9.6.3 CSIX-L1 Transmitter State Machine
The CSIX-L1 Transmit State Machine makes state transitions on CWord boundaries. CWords can
be configured to consist of 32, 64, 96, or 128 bits, corresponding to 2, 4, 6, or 8 bus transfers, as
described in
Table 116 .
Table 115. Training Transmitter State Machine Transitions on 16-Bit Bus Transfers
Current State Next State Conditions
Training Control Training Control Until 10 control cycles.
Training Data After 10 control cycles.
Training Data Training Data Until 10 data cycles.
Training Control
After 10 data cycles and repetitions of training
sequence or new training sequence pending.
CSIX
After 10 data cycles and no training sequence pending
and CSIX-L1 mode enabled.
SPI
After 10 data cycles and No training sequence pending
and CSIX-L1 mode disabled.
Tracking Other State Machine States
CSIX CSIX CSIX-L1 SM not entering SPI or Training state.
SPI CSIX-L1 SM entering SPI state.
Training Control CSIX-L1 SM entering Training state.
SPI SPI SPI SM not entering CSIX-L1 or Training state.
CSIX SPI SM entering CSIX-L1 state.
Training Control SPI SM entering Training state.
Table 116. CSIX-L1 Transmitter State Machine Transitions on CWord Boundaries (Sheet 1 of 2)
Current State Next State Conditions
SoF CWord CFrame CWord CFrame longer than a CWord.
Dead Cycle CFrame fits in a CWord.
CFrame CWord CFrame CWord CFrame remainder pending.
SoF CWord
Un-flow-controlled CFrame pending, no training
sequence pending, and SPI mode not enabled.
Dead Cycle
No un-flow-controlled CFrame pending or training
sequence pending or requesting training sequence or
SPI mode enabled and data pending.
Dead Cycle SoF CWord
Un-flow-controlled CFrame pending and no training
sequence pending and no SPI data pending and not
requesting training sequence.
Idle CFrame
No un-flow-controlled CFrame pending and no training
sequence pending and no SPI data pending and not
requesting training sequence.