Motorola MPC8260 - Manual (Page 864)

29-84 MPC8260 PowerQUICC II UserÕs Manual MOTOROLA
Part IV. Communications Processor Module
Table 29-45 describes UTOPIA slave mode signals.
29.12.2.1 UTOPIA Slave Multiple PHY Operation
In multiple PHY UTOPIA slave mode, cells are transferred using cell-level handshake as
deÞned by the UTOPIA level-2 standard. The user should write the ATM controller PHY
address in FPSMR[PHY ID].
29.12.2.2 UTOPIA Clocking Modes
The UTOPIA clock is generated by one of the MPC8260Õs baud-rate generators. The user
should assign one of the baud rate generators to supply the UTOPIA clock. See Chapter 15,
ÒCPM Multiplexing.Ó
Table 29-45. UTOPIA Slave Mode Signals
Signal Description
TxDATA[0Р15]
/[0Р7] Transmit data bus. Carries transmit data from the ATM controller to the master device. TxDATA[15]/
[7] is the msb, TxDATA[0] is the lsb.
TxSOC Transmit start of cell. Asserted by an ATM controller as the Þrst byte of a cell is sent on the TxDATA
lines.
TxENB Transmit enable. An input to the ATM controller. It is asserted by the UTOPIA master to signal the
slave to send data in the next TxCLK cycle.
TxCLAV Transmit cell available. Asserted by the ATM controller to indicate it has a complete cell to transmit.
TxPRTY Transmit parity. Asserted by the ATM controller. It is an odd parity bit over the TxDATA.
TxCLK Transmit clock. Provides the synchronization reference for the TxDATA, TxSOC, TxENB, TxCLAV,
and TxPRTY signals. All of the above signals are sampled at low-to-high transitions of TxCLK.
TxADD[0Ð4] Transmit address. Address bus from the master to the ATM controller used to select the appropriate
M-PHY device.
RxDATA[0Р
15]/[0Р7] Receive data bus. Carries receive data from the master to the ATM controller. RxDATA[15]/[7] is the
msb, RxDATA[0] is the lsb.
RxSOC Receive start of cell. Asserted by the master device whenever the Þrst byte of a cell is being received
on the RxDATA lines.
RxENB Receive enable. Asserted by the master device to signal the slave to sample the RxDATA and
RxSOC signals.
RxCLAV Receive cell available. Asserted by the ATM controller to indicate it can receive a complete cell.
RxPRTY Receive parity. Asserted by the PHY device. It is an odd parity bit over the RxDATA[0Ð15]. If there is
a RxPRTY error and the receive parity check FPSMR[RxP] is enabled, the cell is discarded. See see
Section 29.13.2, ÒFCC Protocol-SpeciÞc Mode Register (FPSMR).Ó
RxCLK Receive clock. Provides the synchronization reference for the RxDATA, RxSOC, RxENB, RxCLAV,
and RxPRTY signals. All the above signals are sampled at low-to-high transitions of RxCLK.
RxADD[0Ð4] Receive address. Address bus from master to the ATM controller device used to select the
appropriate M-PHY device.