PC-9801-92 (NEC)

C bus SCSI I / F. SCSI connector is Amphenol half 50 pin.
This board can not be used on Epson machines due to the Epson check of ROM.
When connecting a cassette tape unit with other SCSI devices
Separate I / F (2 boards required).
There are 2 8 dip switches and 3 3 jumper switches on the board.

· 8 stations dip switch SW1: SCSI ID number of the board, interrupt level,
　DMA channel setting
1-2-3: Set board SCSI ID number
　ON-ON-ON ID 7 (Factory setting)
4-5-6: Setting interrupt level
　OFF-OFF-OFF ■ INT 0
　ON-OFF-OFF INT 1
　OFF-ON-OFF INT 2
　ON-ON-OFF INT 3 (default setting)
　OFF-OFF-ON INT 5
　ON-OFF-ON INT 6
7-8: DMA channel setting
　OFF-OFF DMA # 0 (factory setting)
　ON-OFF ■ Setting prohibited
　OFF-ON DMA # 2
　ON-ON DMA # 3
※ DMA channel is not used in CPU transfer mode.

・ 8 stations dip switch SW2: ROM memory address, body model, Power on
　ROM accessibility setting at the time of
1-2-3-4-5-6-7: Setting ROM memory address + main unit model
　　　　　　　　　　　　(Factory setting: OFF-ON-ON-OFF-ON-ON-OFF)
(1) PC-98XA (high res dedicated machine)
　xxx-OFF-ON-OFF-OFF ■ Memory address \ EC 000 h ~ \ EDFFF h
(2) 8086 loading machine
　OFF-ON-OFF-xx-ON-OFF ■ Memory address D4000h to D5FFFh
(3) V30 loading machine
　OFF-ON-ON-xx-ON-OFF ■ Memory address DC000h to DDFFFh
(4) Normal / high res combined use machine
　OFF-ON-ON-OFF-ON-OFF-ON
(5) The machine with an 80286/386/486 (only for normal mode)
　OFF-ON-ON-OFF-x-ON-ON ■ Memory address \ DC 000 h ~ \ DDFFF h
※ x can be set to ON or OFF, and \ means 0h or Fh.
※ When used with B4670 II (PC-9864L / PC-9864U) in high resolution mode,
　OFF-ON-ON-ON-ON-OFF-OFF (PC-98XA) or OFF-ON-ON-ON-ON-ON-OFF-ON
(Normal / high res combined use machine)
※ The combination with GP-IB interface board is not possible with the 8086 installed machine.
8: Setting of ROM accessibility at Pow on
　ON ■ ROM accessible (factory setting)
　OFF ■ ROM can not be accessed
※ When using two or more boards, use the first I / O port address.
　After setting CCxh, set SW2-8 to ON and set SW-8 for the second and subsequent sheets to OFF.
※ When using this board with PC-9801FA-02 or PC-9821A-E10, this board
　Set SW2-8 to OFF.

・ Three jumper switches SW3 and SW4: I / O port address setting
Below, short pin at SW3 ■ Short pin at SW4 ■ I / O port address
(The I / O port in parentheses is used in CPU transfer mode):
　01-02 ■ 01 02 ■ CC0h, CC2h, CC4h
　　　　　　　　(C84h, C85h, 1C84h, 1C85h, 1C86h, 1C87h) (Factory setting)
　02-03 ■ 01 02 ■ CD0h, CD2h, CD4h
　　　　　　　　(D84 h, D 85 h, 1 D 84 h, 1 D 85 h, 1 D 86 h, 1 D 87 h)
　01-02 ■ 02 03 ■ CE0h, CE2h, CE4h
　　　　　　　　(E84 h, E 85 h, 1 E 84 h, 1 E 85 h, 1 E 86 h, 1 E 87 h)
　02-03 ■ 02 03 ■ CF 0 h, CF 2 h, CF 4 h
　　　　　　　　(F84h, F85h, 1F84h, 1F85h, 1F86h, 1F87h)
※ Except when the cassette magnetic tape unit is connected, use with the factory setting.
　Also, when changing to settings other than the factory settings, turn off SW2-8.

・ Three jumper switch SW5: Data transfer mode setting
　01-02 short ■ DMA transfer (factory setting)
　02-03 short ■ CPU transfer
※ CPU transfer can not be used in the case of 8086 / V30 installed machine and V30 mode.
　Use for DMA transfer (CPU transfer can be used with 80286 or more).
※ When SW2-8 is set to OFF when the cassette magnetic tape unit is connected
　Use in DMA transfer mode for.

When used on an 8086 / V30 machine, the switch beside the card edge connector
Make the pin lever point up.