161 System Registers; System Control Register 1 - Performance Computer PT-VME161 User Manual

161 System Registers

There are six registers on the PT-VME161 that are not defined in the referenced data sheets. These regis-
ters are unique to the PT-VME161, providing control of major functional blocks and status.

System Control Register 1

Bit
0
1
2
3
4
5
6
Address 0D000000h
Byte Read/Write Only
All bits cleared to zero by reset
7 6 5 4 3
Name Function
VPG VMEbus Page bit
1 VME address bit 31=1
0 VME address bit 31=0
LED0 User Programmable LED D0
1 LED on
0 LED off
LED1 User Programmable LED D1
1 LED on
0 LED off
LED2 User Programmable LED D2
1 LED on
0 LED off
LED3 User Programmable LED D3
1 LED on
0 LED off
SDIR SCSI DMA Direction
1 SCSI DMA Write (read from memory)
0 SCSI DMA Read (write to memory)
ECE Enable MC68060 caching of EPAK accesses. See "PT-VME151A Control
Register Differences" on page 96 for in-depth discussion.
Not Used.
Extensible Single Board Computer/Controller User's Manual 61
2 1 0
VPG
LED0
LED1
LED2
LED3
SDIR
ECE
VCE
Performance Computer