Qi 600 Neptune Planar

Neptune Planar Rev. E
Neptune Planar Rev. G
Switch Settings
CMOS Discharge
System Firmware
   ROM Images
   BIOS Revision Levels

Information sourced from Mitsubishi Electric's Insight CD pages.

Neptune Planar Rev. E

Planar Revision History.

Neptune Planar Rev. G

Planar Revision History.

Switch Settings


Pos. On Off
1 Pipeline 386 enable Pipeline 386 disable
2 Pipeline 385 enable Pipeline 385 disable
3 ROM's disabled ROM's enabled
4 Refresh enabled Refresh disabled


Pos. On Off
1 RAM configuration
2 RAM configuration
3 RAM configuration
4 CPU speed select
5 CPU speed select
6 Not currently used
7 *Weitek present Weitek not present
8 Not currently used
* PAL required to enable


Memory Fitted SW2 Position SIMM Capacity
1 2 3 Bank 0 Bank 1
1 MByte Off Off Off 256k -
1 MByte On Off Off 256k -
2 MByte Off On Off 256k 256k
4 MByte Off Off On 1 M -
5 MByte On On Off 256k 1 M
8 MByte On Off On 1 M 1 M
12 MByte Off On On 2 M 1 M
16 MByte On On On 2 M 2 M

Clock Speed

CPU speed MHz SW2 Position
4 5
25 MHz Off On


Pos. Description
A Routes high resolution video clocks
B High resolution video required

SW4 Rev. E / SW53 Rev. G - Ethernet Configuration

All ON - BNC connector enabled All OFF - D-type connector enabled

SW4 Rev. G

Pos. Description
A Routes composite sync pulses to the Video DAC
B Composite sync pulses required

CMOS Discharge

To drain CMOS remove the battery and connect a 10 Ohm resistor between TP13 and TP14.

If no resistor is available then it will take approx. 20 minutes to drain.

System Firmware (POST & BIOS)

Firmware stored in EPROM (2x 64 KB).

ROM Images

qi610223.zip - Qi 600 ROM BIOS 1.02.23 (LO+HI, zipped)

BIOS Revision Levels

BIOS Revision Summary (ver. 1.02.07 - 1.02.23)

Content created and/or provided by:
Louis F. Ohland, Peter H. Wendt, David L. Beem, William R. Walsh, Tatsuo Sunagawa, Tomáš Slavotínek, Jim Shorney, Tim N. Clarke, Kevin Bowling, and many others.

Ardent Tool of Capitalism - MAD Edition! is maintained by Tomáš Slavotínek.
Last update: 05 Dec 2023 - Changelog | Legal Info & Contact