W83977AF Information Storage Devices, Inc, W83977AF Datasheet - Page 141

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

10.5 Logical Device 3 (UART B)
CR30 (Default 0x01 when PNPCSV=0 at POR)
CR31
CR60, CR 61 (Default 0x02, 0xF8 when PNPCSV=0 at POR)
CR70 (Default 0x03 when PNPCSV=0 at POR)
CR71 (Default 0x02, read only)
CRF0 (Default 0x00)
Bit 7-1 : Reserved.
Bit 0 :
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 Serial Port 2 I/O base address [0x100:0xFF8] on 8 byte boundaries.
Bit 7-4 : Reserved.
Bit [3:0] : These bits select IRQ resource for Serial Port 2.
Bit 7-2 : Reserved.
Bit 1 : IRQLEV -- > IRQ Level
Bit 0 : IRQTYPE --> IRQ Type
Bit 7-2 : Reserved.
Bit 1-0 : SUBCLKB1, SUBCLKB0
= 1 Activates the logical device.
= 0 Logical device is inactive.
= 1: High; = 0: Low
= 1: Level trigger; 0: Edge trigger
= 00
= 01
= 10
= 11
UART B clock source is 1.8462 Mhz (24MHz/13)
UART B clock source is 2 Mhz (24MHz/12)
UART B clock source is 24 Mhz (24MHz/1)
UART B clock source is 14.769 Mhz (24MHz/1.625)
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W83977F/ W83977AF
Publication Release Date: March 1998
PRELIMINARY
Revision 0.58