W83977AF Information Storage Devices, Inc, W83977AF Datasheet - Page 144

• Manufacturer Part Number: W83977AF
• Description: W83877TF Plus Kbc, Cir, RTC
• Manufacturer: Information Storage Devices, Inc

CRF0 (Default 0x40)
10.8 Logical Device 6 (IR)
CR30 (Default 0x00)
CR31
CR60, CR 61 (Default 0x00, 0x00)
CR70 (Default 0x00)
CR71 (Default 0x02, read only)
Bit 7-6 : KBC clock rate selection
Bit 5-3 : Reserved.
Bit 2 : = 0 Port 92 disable.
Bit 1 : = 0 Gate20 software control.
Bit 0 : = 0 KBRST software control.
Bit 7-1 : Reserved.
Bit 0 : = 1 Activates the logical device.
Bit 7-2 : Reserved.
Bit 1 : ENRNGCK -- > Enable I/O Range check
Bit 0 : FORIORD --> Forces LDN to respond I/O read
These two registers select IR I/O base address [0x100:0xFF8] on 8 byte boundaries.
Bit 7-4 : Reserved.
Bit [3:0] : These bits select IRQ resource for IR.
Bit 7-2 : Reserved.
Bit 0 : IRQTYPE --> IRQ Type
= 00 Select 6MHz as KBC clock input.
= 01 Select 8MHz as KBC clock input.
= 10 Select 12Mhz as KBC clock input.
= 11 Select 16Mhz as KBC clock input.
= 1 Port 92 enable.
= 1 Gate20 hardware speed up.
= 1 KBRST hardware speed up.
= 0 Logical device is inactive.
Bit 1 : IRQLEV -- > IRQ Level
= 1: High; = 0: Low
= 1: Level trigger; = 0: Edge trigger
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W83977F/ W83977AF
Publication Release Date: March 1998
PRELIMINARY
Revision 0.58