
Physical Layer Interface Controller (PLIC)
MCF5272 ColdFire Integrated Microprocessor User’s Manual, Rev. 3
Freescale Semiconductor
13-25
13.5.13 GCI Monitor Channel Transmit Registers (P0GMT–P3GMT)
All bits in these registers are read/write and are cleared on hardware or software reset.
for each of the four ports on the MCF5272.
A byte of monitor channel data to be transmitted on a certain port is put into an associated register using
the format shown in
Figure 13-25. A maskable interrupt is generated when this byte of data has been
successfully transmitted.
15
10
9
8
7
0
Field
—
L
R
M
Reset
0000_0000_0000_0000
R/W
Read/Write
Addr
MBAR + 0x368 (P0GMT); 0x36A (P1GMT); 0x36C (P2GMT); 0x36E (P3GMT)
Figure 13-25. GCI Monitor Channel Transmit Registers (P0GMT–P3GMT)
Table 13-8. P0GMT–P3GMT Field Descriptions
Bits
Name
Description
15–10
—
Reserved, should be cleared.
9L
Last.
0 Default reset value
1 Set by the CPU. Indicates to the monitor channel controller to transmit the end of message signal on the
E bit. Both PnGMT[L] and PnGMT[R] must be set for the monitor channel controller to send the end of
message signal. PnGMT[M7:0] are ignored and 0xFF is sent with the end of message condition
necessitating sending the monitor channel information using PnGMT[R] to control the monitor channel
transmitter, followed at the end of the frame by setting PnGMT[L] and PnGMT[R]. The L bit is automatically
cleared by the GCI controller.
8
R
Ready.
0 Default reset value.
1 Set by the CPU. Indicate to the monitor channel controller that a byte of data is ready for transmission.
Automatically cleared by the GCI controller when it generates a transmit acknowledge (ACK bit in PGMTS
register) or when the L bit is reset.
7–0
M
Monitor channel data byte. Written by the CPU when a byte is ready for transmission.