
Here are the PAL switch settings and hardware notes I recorded from my Sega / Cross Systems Sophia.
I originally called these the “factory settings”.
I do not have enough surviving documentation to establish that every switch position shown here was a universal PAL factory default, so it is safer to describe them as the settings recorded from my unit.
One useful troubleshooting note from the time: if no video appears, it may be worth trying the NTSC / PAL switch in the NTSC position.
I remember having some display trouble around this setting, although I did not fully characterise it.
Switch Bank 1
- AREA0 = ON
- AREA1 = ON
- AREA2 = OFF
- AREA3 = OFF
- NTSC/PAL = ON
- 6 = OFF
- 7 = OFF
- 8 = OFF
Switch Bank 2
- WS0 = OFF
- WS1 = OFF
- SCSIBOOT = OFF
- SCSI ON = OFF
- SIMMCART = ON
- 6 = OFF
- 7 = OFF
- 8 = ON
Hardware notes
- My Sophia arrived with one 8 MB Samsung KMM5362000B2G-7 SIMM, rated at 70 ns.
- Sega’s Programming Box documentation supports up to four 8 MB SIMMs, giving a maximum of 32 MB.
- The A-Bus board is the upper board carrying the SIMM sockets.
- The cable from the A-Bus area to the SH-2 CPU cards is the branched EVA-board power cable I had been investigating.
Things I hadn’t worked out yet
- What are the HCD63 markings on Sophia?
- What is the EVA-PO-S / EVA-P0-S 4-pin header CN10 connector that joins CN4 on the SH-2 CPU Card?
- 171-6692B (ADK-7000) vs 171-6692D (HCD63) - manufacturers perhaps?
Until we know, I guess we’ll never know.