PCI Setup Utility Version 1.50 for PC-9821 (PCIセットアップディスク v1.50) English Transla

[sampson]

This is a utility that is used to reserve address space on the C-Bus and PCI cards so that DOS will not run into memory conflicts. This utility is helpful for users that are using a PC-9821 that has both a C-Bus and PCI bus. Included are two archives, one is a bootable floppy while the other is meant to be installed to \PCISETUP\.

The application has been fully translated to English along with the help menus. Pressing HELP on any screen will bring a description of the page and what is to be entered. You will need to look up the settings for your C-Bus cards and once entered Plug & Play will stop trying to take those addresses, irqs and dma.

From my research 1.50 is the last version of the software and should work on all machines that have PCI including the Pentium Pro and Pentium II models.

The method of operation requires understanding the hardware in your computer and what it is utilizing for IRQ, DMA and memory range if PCI. A helpful resource is something like the dipswitch configuration pages I ran through a translator at https://sammargh.github.io/pc98/

Loading the software as an example I would go into the slot my -86 sound card is plugged into and reserve INT5 (IRQ12) on the slot. By doing this and using PCI cards I won't run into an IRQ conflict when the bus mastering attempts to assign resources to the cards in there. Another example is my PC-9821RV20 comes with SCSI built in, but is default to INT0(IRQ3). If I have another card that needs that IRQ which cannot be moved off then I can use the PCI utility to move SCSI to a new IRQ.

Once you've registered everything appropriately you should be free of resource conflicts and be able to use DOS/Windows much better on the machine.

[sampson]

As for how to use this utility:
For identifying which built-in cards are which, on my PC-9821RV20 I disabled the Ethernet card and then viewed the setup utility. The disabled slot will have no IRQ or memory range allocated which helps figuring the cards out. The disabled slot shows up as "Used" on the settings utility with no way to modify. If you look at the slots for both PCI & C-Bus you will see that they are numbered. My PC having 4 C-Bus slots I need to run pcisetup.exe with /C4 as the flag to tell the program I have 4 C-Bus slots. Following is the current card configuration on my PC:

C-Bus
Slot 1: IF-SEGA (Auto)
Plug & Play

Slot 2: PC-9801-86 sound card
INT 5 (IRQ 12)

Slot 3: MPU
INT 2 (IRQ 6)

Slot 4: empty

Built-in PC-9801-118 is disabled as the card conflicts with PC-9801-86's FM range.

PCI
Slot 1: Onkyo sound card (Auto)
Plug & Play
IRQ 3
Slot 2: MGA-2064W (Auto)
IRQ 9
Slot 3: Voodoo 2 (Auto)
Plug & Play

Built-In PCI
On-Board #1: SCSI - AHA-2940 equivalent (Auto)
I/O Address: 6800-68ff
Memory address: dc000-dc7ff
IRQ: 3
On-Board #2: Ethernet (Auto)
I/O Address: 6000-601f
IRQ: 5

With everything laid out above we can see I don't have any conflicts currently, however Windows COULD decide to use IRQ12 or IRQ6 for devices plugged in which would break my audio.. oh no! So for my configuration I need to set C-Bus slot 2 to IRQ 12 and slot 3 to IRQ 6. You'll also notice that my sound card and SCSI are sharing the same interrupt. This can potentially cause performance issues, and if I wanted to could move the Onkyo sound card to a different IRQ. This works because both cards are PCI and PC-9821 does support IRQ sharing across PCI devices.

Here is a general INT/IRQ table taken from a pc setup guide which gives some standard IRQ reservations and some that were assigned by the user:


Comparing this to my configuration we can see that IDE (IRQ9) is being used by my 2D graphics card. This is fine, as I do not have any IDE devices on the computer and have it disabled. The main IRQs that you can use to assign to devices across computers are 3,5,6 and 12 without causing hardware conflicts on a base machine. On my machine however 6 is an invalid setting and I'm only allowed 3,5,9 and 12 for IRQ setting. This means if I want to split SCSI & audio off the same IRQ I would need to remove a device as I've used all available IRQ for dedicated cards.