BM-98 (三井石油化学工業)

C bus bus master SCSI board.Two jumper switches on the board, 2 x 2
1 jumper switch, 2x4 1x jumper switch, 8x dip switch
There are two.

・ 2 x 4 jumper switch JB1: Setting of hold request channel
　HRQ1, HLA1 short: HRQ / HLA channel 1
　HRQ2, HLA2 short: HRQ / HLA channel 2 (factory setting)

・ 2 jumper switches, 2 × 2 jumper switches JB3: transfer mode, I / O
　Port address setting
【2 jumper switch】
　FORCE DMA open: forced DMA transfer
　FORCE DMA open: bus master transfer (factory setting)
【2 x 2 series jumper switch】
　IOA0 short, IOA1 short: CC0h to CC7h
　IOA0 short, IOA1 open: CD0h to CD7h
　IOA0 open, IOA1 short: CE0h to CE7h
　IOA0 open, IOA1 open: CF0h to CF7h

・ 8-station dip switch SW1: SCSI-ID, interrupt level, DMA channel setting
1-2-3: SCSI-ID setting
　0FF-0FF-0FF: ID = 0
  ON-OFF-OFF: ID = 1
  OFF-ON-OFF: ID = 2
  ON-ON-OFF: ID = 3
  OFF-OFF-ON: ID = 4
  ON-OFF-ON: ID = 5
  OFF-ON-ON: ID = 6
  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
  OFF-OFF-ON: INT 5 (default setting)
  ON-OFF-ON: INT 6
7-8: DMA channel setting
　OFF-OFF: DMA # 0
  OFF-ON: DMA # 2
  ON-OFF: Setting prohibited
  ON-ON: DMA # 3 (factory setting)

・ 8 stations dip switch SW2: Local memory address, setting of main unit model
1-2-3: Local memory address (normal) setting
　OFF-OFF-OFF: D0000h to D0FFFh
　ON-OFF-OFF: D2000h to D2FFFh
　OFF-ON-OFF: D4000h to D4FFFh
　ON-ON-OFF: D6000h to D6FFFh
　OFF-OFF-ON: D 8000 h to D 8 FFF h
　ON-OFF-ON: DA000h to DAFFFh
　OFF-ON-ON: DC000h to DCFFFh (factory setting)
　ON-ON-ON: DE 000 h to DEFFF h
4-5: Setting of local memory address (high res)
　OFF-OFF: E8000h to E8FFFh
　ON-OFF: EA000h to EAFFFh
　OFF-ON: EC000h to ECFFFh (factory setting)
　ON-ON: EE000h to EEFFFh
6-7: Setting of machine model
　OFF-OFF: PC-98XA
  ON-OFF: CPU is the model of 8086 / V30
　OFF-ON: Normal / High res combined machine
　ON-ON: CPU model 286/386/486 (default setting)
8: ROM BIOS enable / disable setting
　ON: Enabled (factory setting)
　OFF: Disabled