VCM-DAS-3 Reference Manual
17
Registers
I/O Port Mapping
In enhanced mode, the VCM-DAS-3 operates occupies 16 ports in the I/O map. Eleven ports are
mapped to functional registers, and the remaining five ports are decoded by the board and cannot
be used by other PC/104 modules.
Table 6: Enhanced Mode I/O Port Addresses
Write Register
Read Register
I/O Port Address
As Shipped
Address
–
PLDVER
Base A F
0x30F
–
–
Base A E
0x30E
–
–
Base A D
0x30D
–
–
Base A C
0x30C
–
–
Base A B
0x30B
ENCTRL
ENCTRL
Base A A
0x30A
ENDATHI
ENDATHI
Base A 9
0x309
ENDATLO
ENDATLO
Base A 8
0x308
DIOCTRL
DIOCTRL
Base A 7
0x307
DIOC
DIOC
Base A 6
0x306
DIOB
DIOB
Base A 5
0x305
DIOA
DIOA
Base A 4
0x304
EXTRIG
EXTRIG
Base A 3
0x303
DACSEL
–
Base A 2
0x302
DACHI
DACALL1
Base A 1
0x301
DACLO
DACALL0
Base A 0
0x300
In compatible mode, the VCM-DAS-3 operates occupies eight ports in the I/O map, all of which
are functional.
4
4