
78Q8430 Data Sheet
DS_8430_001
64
Rev. 1.2
7.6.17 PROM Control Register
Name: PRCR
Reset Val: 0x0000_0000
Block: CTL
Address: 0x14C
Bits
Type
Default
Description
31:9
X
0000
Reserved
8
RW
0
Busy
Writing a 1 initiates the EEPROM data transfer. The hardware will clear
the bit when the operation completes.
7:6
RW
0x0
Operation
1 1 = Erase.
1 0 = Read.
0 1 = Write.
0 0 = Enable or Disable Writing, as specified in PROM Addr:
[5:4] = 11, Enable
[5:4] = 00, Disable
5:0
RW
0x00
PROM Addr
Address of the EEPROM to access.
7.6.18 MAC Control Register
Name: MCR
Reset Val: 0x0080_0050
Block: CTL
Address: 0x154
Bits
Type
Default
Description
31:28
X
0000
Reserved
27
RW
0
Tx Enable
When this bit is clear transmitting stops immediately.
26
RW
0
Tx Halt
When this bit is set transmitting stops at the end of the current frame.
25
RW
0
Rx Enable
When this bit is clear receiving stops immediately.
24
RW
0
Rx Halt
When this bit is set receiving stops at the end of the current frame.
23
RW
1
Rx Drop Error
When this bit is set then an error in the first 256 bytes will cause a
packet to be dropped. If clear, error packets are forwarded to the host.
22
RW
0
Keep Dropped Status
Normally, the status for a dropped frame is not added to the receive
status FIFO. When this bit is set then a status for all frames, including
dropped frames, is added to the receive status FIFO. The status for a
dropped frame will have a size of zero in the
RPSR.21
RW
0
Jumbo OK
Normally frames in excess of the maximum allowed by 802.3 are
flagged as bad. If this bit is set then larger frame sizes are allowed.
20:18
0000
Reserved
17
RW
0
MACRST
Software re-initialization. Setting this bit will also automatically set both
Rx and Tx Halt bits and clear both Rx and Tx Enable bits. This bit is
only cleared by writing a zero.
16
RW
0
MACLOOP
Loopback mode for the MAC.
15:8
X
0x000
Reserved
7
RW
0
No Rx PAD
Strip the padding bytes from the end of received frames that are 64
bytes in length. When the padding is stripped from a frame the CRC is
stripped as well.