Compaq EN Series Technical Reference Manual page 91

Chapter 4 System Support
Configuration Byte 90h, 91h, Total Super Extended Memory Configured
This byte holds the value of the amount of extended system memory that is configured.
The amount is given in 64-KB increments.
Configuration Byte 92h, Miscellaneous Configuration Byte
Default Value = 18h
Bit Function
7..5 Reserved
4 Diskette Write Control:
0 = Disable
1 = Enable
3..1 Reserved
0 Diskette Drive Swap Control:
0 = Don't swap
1 = Swap drive A: and B:
Configuration Byte 93h, PCI Configuration Byte
Default Value = 00h
Bit Function
7 Onboard SCSI Status:
0 = Hidden
1 = Active
6 Onboard NIC Status:
0 = Hidden
1 = Active
5 Onboard USB Status:
0 = Hidden
1 = Active
3 Reserved
2 ISA Passive Release:
0 = Enabled
1 = Disabled
1 PCI Bus Master Enable
0 = Enabled
1 = Disabled
0 PCI VGA Palette Snoop
0 = Disable
1 = Enable
If palette snooping is enabled, then a primary PCI graphics card may share a common palette
with the ISA graphics card. Palette snooping should only be enabled if all of the following
conditions are met:
An ISA card connects to a PCI graphics card through the VESA connector.
The ISA card is connected to a color monitor.
The ISA card uses the RAMDAC on the PCI card
The palette snooping feature (sometimes called "RAMDAC shadowing") on the PCI card is
enabled and functioning properly.
4-42 Compaq Deskpro EN Series of Personal Computers
Desktop and Minitower Form Factors
Third Edition - September 1998