PC87393VJG National Semiconductor, PC87393VJG Datasheet - Page 49

• Manufacturer Part Number: PC87393VJG
• Description: IC, SUPER I/O DEVICE, TQFP-100
• Manufacturer: National Semiconductor

Specifications of PC87393VJG

• Data Rate: 2Mbps
• Supply Voltage Range: 3V to 3.6V
• Logic Case Style: TQFP
• No. Of Pins: 100
• Operating Temperature Range: 0°C to +70°C
• Termination Type: SMD
• Transceiver Type: Interface
• Rohs Compliant: No

2.0 Device Architecture and Configuration
2.11.4 Drive ID Register
This read/write register is reset by hardware to 00h. This register controls bits 5 and 4 of the TDR register in the Enhanced
mode.
Location:
Type:
Usage Hints: Some BIOS implementations support automatic media sense FDDs, in which case bit 5 of the TDR register
in the Enhanced mode is interpreted as valid media sense when it is cleared to 0. If drive 0 and/or drive 1 do not support
automatic media sense, bits 1 and/or 3 of the Drive ID register should be set to 1 respectively (to indicate non-valid media
sense) when the corresponding drive is selected and the Drive ID bit is reflected on bit 5 of the TDR register in the Enhanced
mode.
Bit
Name
Reset
7-4
3-2
1-0
Bit
Reserved
Drive 1 ID. When drive 1 is accessed, these bits are reflected on bits 5-4 of the TDR register, respectively.
Drive 0 ID. When drive 0 is accessed, these bits are reflected on bits 5-4 of the TDR register, respectively.
Index F1h
R/W
7
0
6
0
Reserved
5
0
Description
49
4
0
(Continued)
3
0
Drive 1 ID
2
0
1
0
Drive 0 ID
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