Laptop User Manual
Set Environment to Bug/Operating System
MVME166IG/D2 A-11
A
VMEC2 GCSR Group Base Address CC Specifies the group address 
($FFFFXX00) in Short I/O for 
this board. Default = $CC. 
VMEC2 GCSR Board Base Address 00 Specifies the base address 
($FFFFCCXX) in Short I/O for 
this board. Default = $00. 
VMEbus Global Time Out Code 01 This controls the VMEbus 
timeout when systems 
controller. Default $01 = 64 µs. 
Local Bus Time Out Code 00 This controls the local bus 
timeout. Default $00 = 8 µs. 
VMEbus Access Time Out Code 02 This controls the local bus to 
VMEbus access timeout. Default 
$02 = 32 ms. 
The special 166Bug parameters that can be configured using ENV are as follows.
VSBC2 Installed [Y/N] Y This is set depending on the 
existence of a VSBchip2 on the 
board. It can be overridden with 
this ENV option. 
VSBC2 Interrupt Vector Base 0E Vector passed back to the VSB 
master during the Status/ID 
transfer phase of an interrupt-
acknowledge cycle, if the 
VSBchip2 wins interrupt 
arbitration.  Default = 0E. 
VSBC2 Local Interrupt Vector Base 00 The value here is part of the 
interrupt vector supplied on the 
local bus during an interrupt 
acknowledge cycle. The lower 4 
bits are reserved (and are read-
only, as zeroes). Bits 4 through 7 
are programmable.  Default = 00. 
VSBC2 Slave Starting Address #1 00000000 Beginning address of an address 
range for the first VSB to local 
bus map decoder. Only the 
upper 16 bits of this field are 
significant (or used). Default = 
00000000. 
VSBC2 Slave Ending Address #1 00000000 Ending address of an address 
range for the first VSB to local 
bus map decoder. Only the 
upper 16 bits of this field are 
significant (or used). Default = 
00000000. 
Table A-1. ENV Command Parameters (Continued)
ENV Parameter and Options Default Meaning of Default










