IF-2771 (ICM)

Non-multi-vendor compatible C bus with connector for add-on board connection
Bus master SCSI I / F. 55 boards upward compatible.Bus master in Windows 95
FIFO transfer is faster than transfer. Supports models with 286 or more CPUs
(Not available in V30 mode).DMA used by this board in PC-98XA
Use in the slot where channel is available (channel 0: slot
1, 2, 3, 5 / channel 2: slot 2 / channel 3: slot 3, 4, 5).
The system clock is used in bus master mode with PC-386S.
Possible only at 25 MHz.Power consumption is 260mA (Typical) when not accessing,
Access time 390mA (MAX).
Two 8-deep dip switches and one 4-deep dip switch on the board,
There are 2 2 jumper switches and 4 3 jumper switches.
Silk printing of jumper switches on the board is misleading,
The position of the jumper switch, when looking at the card edge to the right,
     JP3 JP5
     JP4 JP6
Is correct.

· 8 stations dip switch SW1: SCSI ID number of this board, interrupt level,
　DMA channel setting
1-2-3: SCSI ID number setting
　OFF-OFF-OFF 0
　ON-OFF-OFF 1
　OFF-ON-OFF 2
　ON-ON-OFF 3
　OFF-OFF-ON 4
　ON-OFF-ON 5
　OFF-ON-ON 6
　ON-ON-ON 7 (default setting)
4-5-6: Setting interrupt level
　OFF-OFF-OFF INT 0 (factory setting)
　ON-OFF-OFF INT 1
　OFF-ON-OFF INT 2
　ON-ON-OFF INT 3
　OFF-OFF-ON INT 5
　ON-OFF-ON INT 6
7-8: DMA channel setting
　OFF-OFF # 0 (default setting)
　ON-OFF ■ Setting prohibited
　OFF-ON # 2
　ON-ON # 3

・ 8 stations dip switch SW2: ROM local memory address
(1-2-3-4-5), Setting of main unit model (6-7)
(8 is always ON. Default setting: OFF-ON-ON-OFF-ON-ON-ON-ON)
The following shows the main unit model ■ DIP switch setting ■ ROM local
In order of memory address:
　PC-98 XA xxx-OFF-ON-OFF-OFF-ON ■ \ EC 000 h ~ \ ECFFF h
　Normal / Hi-Res dual-purpose machine ■ OFF-ON-ON-OFF-ON-OFF-OFF-ON-ON
　　　■ Normal mode \ DC 000 h ~ \ DCF FF h
　　　/ During high res mode \ EC 000 h ~ \ ECFFF h
　Other than the above ■ OFF-ON-ON-xx-ON-ON-ON ■ \ DC 000 h ~ \ DC F FF h
　※ x can be ON or OFF.Also, \ is 0h or Fh.
　※ We have high res mode when using with B4670II (PC-9864L)
　　Be sure to turn on SW2 4-5 on the main unit.In this case local
　　The memory address is set to \ EE000h to \ EEFFFh.

・ 4 stations dip switch SW3: I / O port address, transfer mode setting
1-2: I / O port address setting
　ON-ON CCxh (default setting)
　OFF-ON CDxh
　ON-OFF CExh
　OFF-OFF CFxh
　※ x is 0, 2, 4 in DMA / bus master mode, and in FIFO mode
　　Represents 0, 2, 4, 6
　※ Access from DISK BIOS is not available if it is set other than factory setting
　　become unable.Use special hardware such as PC-98B55
　　If only change it.
3-4: Transfer mode setting
　OFF-ON Synchronous bus master transfer (factory setting)
　ON-OFF W-FIFO transfer
　OFF-OFF DMA transfer
　※ A SCSI device supporting synchronous transfer and a device with asynchronous transfer are mixed
　If you want to use a transfer method for each device automatically
　Switch.

・ Three jumper switch JP1: Prohibition of change (Factory setting: 2-3 short circuit)

・ Three jumper switch JP2: Prohibition of change (Factory setting: Short between 1 and 2)

・ 2 jumper switch JP3: Do not change (default setting: open)

・ 2 jumper switch JP4: Setting the maximum speed of synchronous bus master transfer
　Open up to 10MB / s (default setting)
　Short ■ Maximum 5MB / s
　* There is no need to change settings if all SCSI devices are asynchronously transferred.

・ Three jumper switch JP5: Prohibition of change (Factory setting: 2-3 short circuit)

・ 3 jumper switch JP6: Change prohibited (Factory setting: 2-3 short circuit)

When using the EMS driver, the EMS page frame is
Be careful not to overlap local memory addresses.Also used with GP-IP board
Can not be used in FIFO mode (because some I / O port addresses overlap).

ICM does not guarantee the use of HDD via I / O expansion unit.