Mac Plus, SE/30 Add external LED for "Activity"?

[Admiral Ackbar]

Hi all. Is there a place on the SE/30 motherboard where wires could be run to an external LED to make it light/active on "heavy" CPU operations, or disk operations, or network operations? Just looking for something to blink when the system is active. Kind of like the CPU lights on the ZipGSX in a IIGS and etc.

Similar to the question at https://68kmla.org/bb/index.php?threads/macintosh-se-30-activity-led-amber.49476/ I think, but not quite.

Thanks.

 

[Admiral Ackbar]

Even better. Something like this to show activity. This thing takes 3.5mm as input, but if there was something that could be clamped into a CPU pin (for example similar to how the PDSROM clamps on pin 27 IIRC) with the other end stimulating this display, that would be cool. Pure BW 1-bit fun.

https://www.aliexpress.us/item/3256807799627349.html?

Stick this in a 3d-printed housing and stick it in front of the Mac to watch it "think".

 

[zigzagjoe]

There really isn't any signal that will provide what you're looking for without additional logic. The HDD LED on your SCSI HDD/emulator is your best bet.

 

[Admiral Ackbar]

There really isn't any signal that will provide what you're looking for without additional logic. The HDD LED on your SCSI HDD/emulator is your best bet.

Understood. So I looked around for docs on the SCSI2SD and it doesn't appear to have LED pinouts on its own. Hmmmm...

 

[Admiral Ackbar]

The hunt continues.
https://www.amazon.com/vdp/0f1c24c2...B0F27W6ZR1&ref=cm_sw_em_r_ib_dt_B8RlITxrUgmSu

 

[Mk.558]

Try to use clean links when possible.

https://www.amazon.com/dp/B0F27W6ZR1/

The SCSI2SD does have pinouts. One of the more popular ones, the V5.2 has the holes for adding a 2-pin header for an activity light. Shown here is a V6, with the ZuluSCSI very much similar for this discussion.

https://www.scsi2sd.com/images/5/54/SCSI2SD-V6-Rev2020c.jpg

 

[Admiral Ackbar]

There really isn't any signal that will provide what you're looking for without additional logic. The HDD LED on your SCSI HDD/emulator is your best bet.

It seems like I am looking for a commercial venture for someone else with actual talent.
A Raspberry Pi Zero taking a lead from "somewhere" on the motherboard when a cool activity is happening that is variable (eg CPU cache misses), and powering the 1-inch oscilloscope/vu-meter/gauge display at 1-bit, in a 3d-printed housing matching any of the Compact Mac paint colors, shaped like a miniaturized 3.5 drive or something shaped to fit on top of a keyboard.
Or as Mr. Zig already mentioned, something generic that expects to be fed signal from a SCSI2SD since they are so prevalent.
hmmm