QT2022/32 - Data Sheet: DS3051
A AMCC-specific DOM write command has been added. The write control is via MDIO vendor specific register
1.C004h. The write can be a full 256 byte write or a single byte write to the address specified in MDIO register bits
1.C002h.7:0. The write command status registers have been added to the unused/undefined upper bits of the
DOM read command register. This allows for clearing of either read or write command failures with a single MDIO
register read. The QT2022/32 EEPROM_PROT pin must be pulled low to enable writing to the DOM MDIO regis-
ters and to the DOM device registers.
Table 36: DOM Control Registers
PMA/PMD Vendor Specific
PMA/PMD Vendor Specific
DOM Control/Status Register
1.A100h
EEPROM Checksum/
DOM Write Control Register
1.C004h
Bit
0
1
DOM Read Commands / Update Rate (R/W)
bit1 bit0 Command
DOM Write Command (R/W)
bit 11 bit10 Command
0
0
1
0
1
write of 00 initiates a single update of MDIO DOM registers
0
0
1
1
0
1
0
1
idle, default
reserved
write 1 byte
write 256 bytes
0
1
1
periodic update of MDIO DOM registers every 60 seconds
periodic update of MDIO DOM registers every 10 seconds
periodic update of MDIO DOM registers every 1 second
2
3
DOM Read Command Status (RO, LH)
bit3 bit2 Command Status
DOM 256 byte write cycle burst size (R/W)
size bit 15 bit14
0
0
1
1
0
1
0
1
no command
1
8
0
0
1
1
0
1
command completed
command in progress
previous command failed
default
16
1
0
1
4
5
6
7
8
9
reserved (RO)
reserved (RO)
reserved (RO)
reserved (RO)
reserved (RO)
reserved (RO)
reserved (RO)
reserved (RO)
reserved (RO)
reserved (RO)
reserved (RO)
reserved (RO)
reserved (RO)
EEPROM calculated checksum
(RO)
10
11
12
13
DOM Write Command Status (RO, LH)
bit 13 bit12 Command status
0
0
1
1
0
1
0
1
no command
command completed
command in progress
previous command failed
14
15
reserved (RO)
reserved (RO)
Before doing a DOM MDIO register write and subsequent DOM device write, the DOM must be idle and not be in
periodic update mode. This is to ensure that a DOM read does not overwrite the DOM MDIO registers before data
has been transferred to the DOM device.
If a DOM (NVR) device access is queued and an NVR (DOM) device access which is in progress fails, then the
NVR (DOM) command failure flag is set and the DOM (NVR) device access is allowed to proceed. No NVR (DOM)
commands are accepted while the NVR (DOM) command failure state is set. this state must be cleared before
another NVR (DOM) command can take place.
88
AppliedMicro - Confidential & Proprietary
Revision 5.11
AMCC [ APPLIED MICRO CIRCUITS CORPORATION ]
