Freescale Semiconductor MPC8260 - Manual (Page 837)

Serial Management Controllers (SMCs)
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor 27-25
describes how to safely disable and reenable the SMC. Simply clearing and setting TEN may not be
enough.
27.4.6 SMC Transparent Commands
Table 27-10 describes transmit commands issued to the CPCR.
Table 27-11 describes receive commands issued to the CPCR.
27.4.7 Handling Errors in the SMC Transparent Controller
The SMC uses BDs and the SMCE to report message send and receive errors.
Table 27-10. SMC Transparent Transmit Commands
Command Description
STOP
TRANSMIT
After hardware or software is reset and the channel is enabled in the SMCM, the channel is in transmit
enable mode and polls the first BD. This command disables transmission of frames on the transmit
channel. If the transparent controller receives this command while sending a frame, it stops after the
contents of the FIFO are sent (up to 2 characters). The TBPTR is not advanced to the next BD, no new
BD is accessed, and no new buffers are sent for this channel. The transmitter sends idles until a
RESTART TRANSMIT command is issued.
RESTART
TRANSMIT
Starts or resumes transmission from the current TBPTR in the channel TxBD table. When the channel
receives this command, it polls the R bit in this BD. The SMC expects this command after a
STOP
TRANSMIT is issued. The channel in its mode register is disabled or after a transmitter error occurs.
INIT TX
PARAMETERS
Initializes transmit parameters in this serial channel to reset state. Use only if the transmitter is disabled.
The
INIT TX AND RX PARAMETERS command resets transmit and receive parameters.
Table 27-11. SMC Transparent Receive Commands
Command Description
ENTER HUNT
MODE
Forces the SMC to close the current receive BD if it is in use and to use the next BD for subsequent
data. If the SMC is not receiving data, the buffer is not closed. Additionally, this command causes the
receiver to wait for a resynchronization before reception resumes.
CLOSE RXBD Forces the SMC to close the current receive BD if it in use and to use the next BD in the list for
subsequent received data. If the SMC is not in the process of receiving data, no action is taken.
i NIT RX
PARAMETERS
Initializes receive parameters in this serial channel to reset state. Use only if the receiver is disabled.
The
INIT TX AND RX PARAMETERS command resets receive and transmit parameters.