beautypg.com

D.22 dmasts – Intel 386 User Manual

Page 592

background image

D-27

SYSTEM REGISTER QUICK REFERENCE

D.22 DMASTS

DMA Status
DMASTS
(read only)

Expanded Addr:
ISA Addr:
Reset State:

F008H
0008H
00H

7

0

R1

R0

TC1

TC0

Bit Number

Bit Mnemonic

Function

7–6

Reserved. These bits are undefined.

5

R1

Request 1:

When set, this bit indicates that channel 1 has a hardware request
pending. When the request is removed, this bit is cleared.

4

R0

Request 0:

When set, this bit indicates that channel 0 has a hardware request
pending. When the request is removed, this bit is cleared.

3–2

Reserved. These bits are undefined.

1

TC1

Transfer Complete 1:

When set, this bit indicates that channel 1 has completed a buffer
transfer (either its byte count expired or it received an EOP# input).
Reading this register clears this bit and clears TC1 in DMAIS.

0

TC0

Transfer Complete 0:

When set, this bit indicates that channel 0 has completed a buffer
transfer (either its byte count expired or it received an EOP# input).
Reading this register clears this bit and clears TC0 in DMAIS.