IBM PowerPC 405GP

12:13
TFS Transmit (TX) FIFO Size
00
Reserved
01 1 KB
102 KB
11 Reserved
14
Reserved
Always zero
15:16
TRO
Transmit Request 0 Defines the different modes for using
00 Single packet
transmit
channel 0 of EMAC.
01 Multiple packets
10 Dependent mode (bits 17: 18 must also
be programmed to 10)
11 Reserved
17:18
TR1
Transmit Request 1
Defines the different modes for using
00 Single packet
transmit
channel 1 of EMAC.
01 Multiple packets
10 Dependent mode (bits 15:16 must also
be programmed to 10)
11 Reserved
19:31
Reserved
19.7.3 Transmit Mode Register 0 (EMACO_TMRO)
EMACO_ TMRO defines EMAC operating modes during transmit operations (see "EMAC Transmit
Operation" on page 19-5).
EMACO_
TMRO[GNPO, GNP1 , GNPD] are self-clearing. Writing 0 to these fields has no effect.
GNPOGNFD
+ +
t t
311
GNP1 FC
Figure 19·17. Transmit Mode Register 0 (EMACO_TMRO)
0 GNPO
Get New Packet 0 EMACO_TMRO[GNPO] = 0 if.EMAC is
o Writing 0 has no effect.
programmed in dependent mode.
1 Packet ready for transmission on TX
Channel 0
1
GNP1 Get New Packet 1
EMACO_TMRO[GNP1] = 0 if EMAC is
o Writing 0 has no effect.
programmed in dependent mode.
1 Packet ready for transmission on TX
Channel 1
2
GNPD
Get New Packet for Dependent Mode
EMACO_TMRO[GNPD] = 0 if EMAC is not
o Writing 0 to this bit has no effect
programmed in dependent mode.
1 Packet ready for transmission in
EMACO_ TMRO[GNPD] = 1 activates the
dependent mode
EMAC transmit path in dependent mode.
Preliminary
Ethernet Media Access Controller
19-27