D.15 dmais – Intel 386 User Manual

Page 585

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Intel386™ EX EMBEDDED MICROPROCESSOR USER’S MANUAL

D-20

D.15 DMAIS

DMA Interrupt Status
DMAIS
(read only)

Expanded Addr:
ISA Addr:
Reset State:

F019H

00H

7

0

TC1

TC0

CI1

CI0

Bit

Number

Bit

Mnemonic

Function

7–6

Reserved. These bits are undefined.

5

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). This
bit is set only if bit 1 of the interrupt enable register is set. Reading the
DMA status register (DMASTS) clears this bit.

Note: In chaining mode, this bit becomes a don’t care.

4

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). This
bit is set only if bit 0 of the interrupt enable register is set. Reading the
DMA status register (DMASTS) clears this bit.

Note: In chaining mode, this bit becomes a don’t care.

3–2

Reserved. These bits are undefined.

1

CI1

Chaining Interrupt 1:

When set, this bit indicates that new requester and target addresses and
a new byte count should be written to channel 1. This bit is cleared when
new transfer information is written to the channel. (Writing to the most-
significant byte of the target address clears this bit.)

Note: Outside chaining mode, this bit becomes a don’t care.

0

CI0

Chaining Interrupt 0:

When set, this bit indicates that new requester and target addresses and
a new byte count should be written to channel 0. This bit is cleared when
new transfer information is written to the channel. (Writing to the most-
significant byte of the target address clears this bit.)

Note: Outside chaining mode, this bit becomes a don’t care.

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