Publication No. IMP2B-0HH/5
Functional Description 31
3.15.7
Configuration Register 2 – Offset 0x0000000A
Table
3-15 Configuration Register 2
Bits
Mode
Description
Notes
0
Read only
PMC fitted
0 = PMC not fitted
1 = PMC fitted
1
Read/Write Ethernet channel 0 configuration
0 = ETH1 10/100/1000BaseT [Gigabit]
1 = ETH1 10/100BaseT (default)
[Can only be modified when both PHYs are in Reset]
2
Read only
Ethernet channel 1 configuration 0 = ETH2 10/100BaseT (default)
1 = ETH2 unavailable
3
Read only
COM1 configuration
0 = RS422 Termination fitted
1 = RS422 Termination not fitted
4
Read only
COM2 configuration
5
Read only
PMC I/O configuration
a
0 = PMC User I/O 1 to 49 configured
1 = PMC User I/O 1 to 64 configured
15 to 6
Reserved
a.
Software can use bit 5 to detect whether the IMP2B is built for System Controller or ‘Peripheral only’/‘Limited Host, Full
PMC User I/O’ mode.
3.15.8
Control Register 1 – Offset 0x0000000C
Table
3-16 Control Register 1
Bits
Mode
Description
Notes
0
Read/Write I
2
C EEPROM write protection
0 = I
2
C EEPROM writable
1 = I
2
C EEPROM write protected (default)
NVRAM Write Enable Link (P5 3-4)
to write a ‘0’].
1
Read/Write COM1 Transceiver Driver Skew Control A
0 = COM1_SPA low (default)
1 = COM1_SPA high
2
Read/Write COM1 Transceiver Driver Skew Control B
0 = COM1_SPB low (default)
1 = COM1_SPB high
3
Reserved
4
Read/Write cPCI Arbiter Mode
0 = Fixed Priority
1 = ‘Round Robin’ (default)
5
Read/Write Ethernet PHY0 COMA Mode
0 = PHY in normal mode (default)
1 = PHY in COMA mode
A 10ms reset is required once COMA mode is exited
6
Read/Write Ethernet PHY2 COMA Mode
7
Read/Write Ethernet PHY0 Reset
0 = PHY in reset (default)
1 = PHY out of reset
8
Read/Write Ethernet PHY2 Reset
9
Read/Write USB 2.0 Port 0 Power enable (drives PWREN_AA)
0 = USB Power Off (default)
1 = USB Power On
10
Read/Write USB 2.0 Port 1 Power enable (drives PWREN_AB)
12 & 11
Reserved
13
Read/Write GPIO External Buffer Enable
0 = Buffer enabled
1 = Buffer disabled (default)
14
Read/Write Disco5, Timer/Counter 2 to Timer/Counter 3 cascade 0 = MPP(22) tri-state (default)
1 = MPP(17) drives MPP(22)
15
Read/Write cPCI Interrupt Monitoring
0 = Interrupt monitoring enabled (default if host)
1 = Interrupt monitoring disabled