Juko XT ST-12

Mainboard top view Description paper that i got shipped with my board

Chipset

The whole board has a 8-bit bus. There are two slots for ROM chips, they are likely mapped to successive locations.

There is no RTC or NVRAM. The BIOS settings are entered via on-board jumpers.

Connectors

Control & status header

The headers for the switches and LEDs are on the bottom right of the picture. Starting from this corner and moving up:

Writing on the PCB adjacent to these connectors indicates their purpose.

BIOS settings

Between the processor and the host bridge is a 8-bit DIP switch. The switches are numbered:

Nearby there is a single additional jumper enabling an extra wait state on the ISA bus. You should keep this enabled if the board is running with more than 4.77 MHz, like when turbo is enabled.