Core Logic Module - ISA Legacy Register Space

32579B

 

 

Table 6-46. Programmable Interrupt Controller Registers (Continued)

Bit

Description

 

 

 

 

 

 

1

IRQ1 / IRQ9 Mask.

 

 

 

0: Not Masked.

 

 

 

1: Mask.

 

 

 

 

 

 

0

IRQ0 / IRQ8 Mask.

 

 

 

0: Not Masked.

 

 

 

1: Mask.

 

 

 

 

 

 

 

I/O Port 020h / 0A0h

Master / Slave PIC OCW2 (WO)

 

 

 

 

7:5

Rotate/EOI Codes.

 

 

 

000: Clear rotate in Auto EOI mode

100: Set rotate in Auto EOI mode

 

001: Non-specific EOI

101: Rotate on non-specific EOI command

 

010: No operation

 

110: Set priority command (bits [2:0] must be valid)

 

011: Specific EOI (bits [2:0] must be valid)

111: Rotate on specific EOI command

 

 

 

4:3

Reserved. Must be set to 0.

 

 

 

 

2:0

IRQ Number (000-111).

 

 

 

 

 

 

I/O Port 020h / 0A0h

Master / Slave PIC OCW3 (WO)

 

 

 

7

Reserved. Must be set to 0.

 

 

 

 

 

6:5

Special Mask Mode.

 

 

 

00: No operation.

 

 

 

01: No operation.

 

 

 

10: Reset Special Mask Mode.

 

 

11: Set Special Mask Mode.

 

 

 

 

4

Reserved. Must be set to 0.

 

 

 

 

3

Reserved. Must be set to 1.

 

 

 

 

 

2

Poll Command.

 

 

 

0:

Disable.

 

 

 

1:

Enable.

 

 

 

 

 

1:0

Register Read Mode.

 

 

00: No operation.

 

 

 

01: No operation.

 

 

 

10: Read interrupt request register on next read of Port 20h.

 

 

11: Read interrupt service register on next read of Port 20h.

 

 

 

 

 

 

I/O Port 020h / 0A0h

Master / Slave PIC Interrupt Request and Service Registers

 

 

 

for OCW3 Commands (RO)

The function of this register is set with bits [1:0] in a write to 020h.

 

 

 

 

Interrupt Request Register

 

 

 

 

 

7

IRQ7 / IRQ15 Pending.

 

 

0:

Yes.

 

 

 

1:

No.

 

 

 

 

 

6

IRQ6 / IRQ14 Pending.

 

 

0:

Yes.

 

 

 

1:

No.

 

 

 

 

 

5

IRQ5 / IRQ13 Pending.

 

 

0:

Yes.

 

 

 

1:

No.

 

 

 

 

 

4

IRQ4 / IRQ12 Pending.

 

 

0:

Yes.

 

 

 

1:

No.

 

 

 

 

 

3

IRQ3 / IRQ11 Pending.

 

 

0:

Yes.

 

 

 

1:

No.

 

 

 

 

 

2

IRQ2 / IRQ10 Pending.

 

 

0:

Yes.

 

 

 

1:

No.

 

 

 

 

 

 

 

 

 

 

AMD Geode™ SC1200/SC1201 Processor Data Book

305

Page 305
Image 305
AMD SC1201 Bit Description IRQ1 / IRQ9 Mask, IRQ0 / IRQ8 Mask, Rotate/EOI Codes, IRQ Number Port 020h / 0A0h, Poll Command