MonSTer jumpers

Location and pinout

On the ST/Mega ST MonSTer there's two jumper blocks, each with 12 pins (2x6). On the STE and Mega STE versions there's a single jumper block with 2x12 pins.

ST and Mega ST

Jumper block 1.

Jumper block 2.

STE and Mega STE

Jumper block.

Jumpers

TOSSEL

• Open: Boots with TOS at address 0xE00000.
• Closed: Boots with TOS at address 0xFC0000.

You can have one FC0000-TOS and one E00000-TOS per "partition", see next jumper. Please note that both addresses can be used on all types of ST(e).

FLASHSW

• Open: Boots from the TOS-images in "partition 1".
• Closed: Boots from the TOS-images in "partition 2".

When you flash a TOS image you will always flash to the opposite partition of the one you're currently using.

FLASHON

• Open: Boots from MonSTer flash ROM.
• Closed: Boots from motherboard ROMs.

If you somehow manage to "brick" your ST by having only faulty TOS images flashed, you can recover by setting this jumper and reinstall the motherboard TOS ROMs. You will now boot from the motherboard ROMs and can flash the MonSTer ROM again.

IDESW

When this jumper is closed the primary and secondary IDE ports are swapped.

SDA, SCL, GND, 3.3V

Connect your DS1338 RTC to these pins.

Primary LED, Secondary LED

Activity LEDs for the primary and secondary IDE ports.

ACSI

Connect one of these to the ACSI IRQ pin if you want to boot from an IDE device.

• External ACSI port: Pin 10.
• Internal Mega ST ACSI port: PIN 24.
• Internal Mega STE/Stacy ACSI port: Pin 23.

TDI, TMS, TCK, TDO

JTAG pins for flashing the MonSTer firmware.

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Jo Even Skarstein, 2015 ->
joska at atari-forum.com
joska@online.no