System Setup Menu [NEC PC98]
PC-9801DA (introduced in 1990) and later models have the System Setup Menu (システムセットアップメニュー) like the BIOS Setup Menu on the IBM PC, instead of real dip switches on early models.
To enter the System Setup Menu, hold-down HELP key when you turn on or reset the machine.
Example (PC-9821Xn, Xp, Xs)
メインメニュー (Main menu)
- Up, Down key : Move selection
- Return key : Enter
- HOME CLR key : Call default settings
- ESC key : Exit the menu
動作環境 (Operating environment)
| 16MBシステム空間 (16MB System Space) |
切り離す, 使用する (Not use, Use) |
Set "Use" when you run Windows 3.1. |
| サウンド (Sound) |
使用しない, 使用する (Not use, Use) |
Set "Not use" if you install a sound board, or you want to release an interrupt and I/O resources used by the on-board sound hardware. |
| サウンド割り込みチャネル (Sound Interrupt Channel) |
INT0, INT1, INT41, INT5 | You shouldn't change this. |
| マイクボリューム (Mic Volume) |
OFF 小 --+-- 大 (OFF Min --+-- Max) |
Set the volume of Mic-In. |
| ROM BASIC | 使用しない, 使用する (Not use, Use) |
Set "Use" if you want to use a build-in BASIC interpreter. |
ディップスイッチ1 (Dip Switch 1)
| プラズマディスプレイ (Plasma monitor) |
使用しない, 使用する (Not use, Use) |
It is effective only with the Digital RGB out. This model doesn't have it, so I don't know how it effects. |
| フロッピィディスク番号 (Floppy Drive Numbering) |
内蔵 #3, #4, 外付け #1, #2 or 内蔵 #1, #2, 外付け #3, #4 (Internals #3, #4, Externals #1, #2 or Internals #1, #2, Externals #3, #4) |
|
| RS-232C伝送モード (RS-232C Mode) |
BCI同期, ST2同期, 同期刻時機構, 調歩同期 (BCI Sync, ST2 Sync, Sync with received data, Asynchronous) |
|
| 固定ディスクセクタ長 (Sector Length of Fixed Disk) |
512バイト, 256バイト (512 bytes, 256 bytes) |
Set "256 bytes" if you use a disk version of N88-BASIC(86) with the hard disk. |
| グラフィックモード (Graphic Mode) |
拡張, 標準 (Extended, Basic) |
It will be effective only in N88-BASIC(86). Basic: Use 8 colors only. Extended: Use 16 colors chosen from 4096 colors. |
ディップスイッチ2 (Dip Switch 2)
| ターミナルモード指定 (Terminal Mode Selection) |
ターミナルモード, BASICモード (Terminal mode, BASIC mode) |
Set the startup mode of N88-BASIC(86). |
| テキスト画面行数 (Number of Text Lines) |
25行/画面, 20行/画面 (25 lines per screen, 20 lines per screen) |
|
| メモリスイッチ (Memory Switches) |
保持する, 初期化する (Hold, Initialize) |
You can set the Memory Switches by SWITCH command in MS-DOS or switch.n88 in Disk BASIC. |
| 内蔵固定ディスク (Internal Fixed Disk) |
切り離す, 使用する (Not use, Use) |
Set "Not use" when you don't use the hard drive. It releases one DMA channel. Don't remove it physically. The system will become unstable. |
| GDCクロック (GDC Clock) |
5MHz, 2.5MHz | Clock speed of the display controller. Set "2.5MHz" if a compatibility problem has occured. |
ディップスイッチ3 (Dip Switch 3)
| フロッピーディスクモード (Floppy Drive Mode) |
640K, 1M, 自動(640K), 自動(1M) (640K, 1M, Auto(640K), Auto(1M)) |
PC98 has two floppy interfaces, 640KB (2DD) and 1MB (2HD).
They use different system resources (interrupt and I/O ports). 1M: Use only the 1MB floppy interface. Auto(1MB): Chosen by a type of floppy disk, or use the 1MB floppy interface when booting from the hard drive. |
| フロッピィモータ制御 (Control Floppy Drive Motor) |
しない, する (No, Yes) |
Stop a spin-motor in floppy drive after 15 seconds passed since the last access. |
| DMAクロック (DMA Clock) |
高速, 互換 (Fast, Compatible) |
Fast: DMA run at 10 MHz, Compatible: DMA run at 5 MHz. |
| 内蔵RAM空間 (Internal RAM Space) |
切り離す、有効にする (Disabled, Enabled) |
Set "Disabled" if you use an expansion board using memory addresses at 80000h-9FFFFh, especially an old memory board released before the EMS specification became standard. |
| CPUモード (CPU Mode) |
High, Low | Choose a clock speed of the CPU. "High" means native speed, and "Low" means the speed equivalent to i486-16MHz. This is depending on the model. |
省電力 (Reducing Power Consumption)
| 固定ディスク制御 (Control Fixed Disk) |
設定する, 設定しない (Set, Not set) |
Set the spin down time (15-60min) of the hard drive. |
入出力デバイス (Input / Output Devices)
| ウィンドウアクセラレータの設定 (Window Accelerator Setting) |
F00, F20, F40, F60 | Select memory address of the Window Accelerator. You need not change it. |
| ディスク接続ユニット (Disk Connection Unit) |
使用しない, 使用する (Not use, Use) |
Set "Use" if you install the Fixed disk drive connection unit (PC-9801FA-03). I don't know how it effects. |
Missing settings of the System Setup Menu
These settings are saved on the CMOS memory with an internal rechargeable battery. It's getting charged during the machine is running. If the battery no longer works and the CMOS has been cleared, the system will show a message "SET THE SOFTWARE DIP-SWITCH" with beeping and broken graphics. Then, settings are initialized and the system starts.
If you encount this issue again after you try charging the battery more than 24 hours, you need replace it.