PC-9821A-E10 (NEC)

SCSI I / F in the PC-9801FA / FS / FX, MATE-A SCSI dedicated slot Windows 95 compatible.
This type of SCSI I / F, including third party products, both MS-DOS and Windows 95
This board boasts the highest transfer rate.SCSI connector is Amphenol half 50 pin.

The board has new and old, and the character of FIFO FSCSI on the big custom chip written NEC
If there is an old type (early type), if it is SAGAT 777 and a new type (latter type.White round seal in a box
But the board of the FIFO FSCSI chip is SAGAT 777
There is also a report that there is a performance equivalent to the chip board, and the performance of this board
(Or new and old), when the board is erected, the IC located on this custom chip
Types (There are two types, NVD 01 00 and NVD 0101, and the latter is assumed to be a newer chip)
Seems to be related as well.Note that there are two types of substrates, G8NVD and G8NVDA.
Although the latter is not necessarily the new board, the FIFO FSCSI-NVD 01 00
There are also combinations of G8 NVDA substrates.

There is a problem that the old board can not start the system from the area exceeding 1GB of HDD.
Although it has been said that there is an e10chk.exe authored by Marimo
The problem is considered to actually exist in the new board.The cause of this problem
Some argue that the problem with the initial MS-DOS 5.0, but actually update MS-DOS 5.0
Even if you deal with a bug on the DOS side, the above SCSI BIOS problem is PC-9821A-E10
Because it is on the side.This "1 GB wall" can not be solved.

In addition, the maximum capacity of the PC-9821A-E10 recognizable HDD is 4.3GB on the old board,
It has been said to be 8.4 G in the new-type board, but this is also a survey using e10chk.exe,
The capacity of the HDD that the SCSI BIOS can recognize regardless of whether the board is new or old is less than 8.4 GB
It has been confirmed.If the area is secured by other I / F, the old board can be up to 8.4GB
There are also reports that recognition is possible, but the results of using e10chk.exe are also negative.

In other words, with PC-9821A-E10, regardless of the board old and new, from the HDD area which exceeds 1024 MB
The system can not be booted, and the maximum capacity of the HDD recognized by SCSI BIOS is less than 8192 MB
It will be.In addition, this "1GB wall", e10pat.bin (IPLWARE) created by Mr. Marimo
It cancels if it applies.

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
* If the IDE HDD is built in MATE-A, the interrupt level is not INT 3
　To do.Also, in this case, since the internal HDD uses DMA # 0,
　Change the internal HDD DMA channel to # 1 with the software dip switch on the main unit
　By doing this, # 0 can be used.

・ 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
(1) MATE-A not equipped with PC-9801FA / FS / FX and high res board
　OFF-ON-ON-OFF-ON-ON-ON ■ Memory address \ DC 000 h ~ \ DDFFF h
(2) MATE-A equipped with high res board
　OFF-ON-ON-OFF-ON-OFF-ON Memory Address:
　　　　　　　　　　　　　 Normal mode \ DC 000 h ~ \ DDFFF h
　　　　　　　　　　　　　 In high resolution mode \ EC 000 h ~ \ EDF FF h
　※ \ means 0h or Fh.
8: Setting of ROM accessibility at Pow on
　ON ■ ROM accessible (factory setting)
　OFF ■ ROM can not be accessed

・ Three jumper switches SW3 and SW4: I / O port address setting
Below, short pin at SW3 ■ Short pin at SW4 ■ I / O port address
Order of:
　01-02 ■ 01 02 ■ CC0h, CC2h, CC4h (factory setting)
　02-03 ■ 01 02 ■ CD0h, CD2h, CD4h
　01-02 ■ 02 03 ■ CE0h, CE2h, CE4h
　02-03 ■ 02 03 ■ CF 0 h, CF 2 h, CF 4 h
※ This setting table is PC-9821A-E10 SCSI interface board issued in 1993
　Although based on the description in the user's manual, this board is PC-9801-92
　Is said to be a dedicated slot version of SCSI, and the actual I / O port address is
　It may be as follows (I / O port in parentheses is CPU transfer
　Used in mode):
　01-02 ■ 01 02 ■ CC0h, CC2h, CC4h
　　　　　　　　(C84h, C85h, 1C84h, 1C85h, 1C86h, 1C87h)
　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)
・ Three jumper switch SW5: Transfer mode setting
　01-02 DMA transfer (DMA MODE) (factory setting)
　02-03 CPU transfer (BUFFER MODE)
Set to DMA transfer when installing Windows 3.1 newly.In addition,
Set to DMA transfer also when using in low mode (V30 mode).