SC2200 NSC [National Semiconductor], SC2200 Datasheet - Page 310

• Manufacturer Part Number: SC2200
• Description: Thin Client On a Chip
• Manufacturer: NSC [National Semiconductor]

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Core Logic Module
I/O Port 020h / 0A0h
I/O Port 020h / 0A0h
I/O Port 020h / 0A0h
The function of this register is set with bits [1:0] in a write to 020h.
Interrupt Request Register
7:5
4:3
2:0
6:5
1:0
Bit
2
1
0
7
4
3
2
7
6
5
Description
IRQ2 / IRQ10 Mask.
0: Not Masked.
1: Mask.
IRQ1 / IRQ9 Mask.
0: Not Masked.
1: Mask.
IRQ0 / IRQ8 Mask.
0: Not Masked.
1: Mask.
Rotate/EOI Codes.
000: Clear rotate in Auto EOI mode
001: Non-specific EOI
010: No operation
011: Specific EOI (bits [2:0] must be valid)
Reserved. Must be set to 0.
IRQ Number (000-111)
Reserved. Must be set to 0.
Special Mask Mode.
00:
01:
10:
11:
Reserved. Must be set to 0.
Reserved. Must be set to 1.
Poll Command.
0:
1:
Register Read Mode.
00:
01:
10:
11:
IRQ7 / IRQ15 Pending.
0: Yes.
1: No.
IRQ6 / IRQ14 Pending.
0: Yes.
1: No.
IRQ5 / IRQ13 Pending.
0: Yes.
1: No.
Table 5-46. Programmable Interrupt Controller Registers (Continued)
No operation.
No operation.
Reset Special Mask Mode.
Set Special Mask Mode.
Disable.
Enable.
No operation.
No operation.
Read interrupt request register on next read of Port 20h.
Read interrupt service register on next read of Port 20h.
(Continued)
Master / Slave PIC Interrupt Request and Service Registers
Master / Slave PIC OCW2 (WO)
Master / Slave PIC OCW3 (WO)
for OCW3 Commands (RO)
310
100: Set rotate in Auto EOI mode
101: Rotate on non-specific EOI command
110: Set priority command (bits [2:0] must be valid)
111: Rotate on specific EOI command
Revision 3.0