PL30 14.5v + External Potentiometer Control (Firmware?)

[Mason10198]

Hello! Outstanding resources here in this repository.

I am looking to modify a PL30 to output 14.5v. I see that there is a firmware here for 14.4v w/o any hardware modifications - would it be possible to make one for 14.5v?

I am also interested in adjusting the output voltage via an external potentiometer, from roughly 12-15v. I see where this was mentioned on #16 , but it is not clear to me if the potentiometer used to adjust the voltage in the video (https://www.youtube.com/watch?v=eh7FzcV9E4g&t=818s) is the only hardware modification required. Is the OVP handled by the firmware in this video, and the potentiometer the only HW mod, and being used simply to adjust the output voltage?

Thank you for any assistance!

[Mason10198]

Codex figured this out for me.

The 14.4v firmware can be adjusted to 14.5v with a small firmware-only patch. The output voltage target is stored as a 32-bit float constant that appears in two duplicated code regions/banks, so both copies need to be changed.

For 14.5v, change the setpoint constant from:

mov.w #0xEF9E, w2
mov.w #0x46E4, w3
; 0x46E4EF9E

to:

mov.w #0x86ED, w2
mov.w #0x46E6, w3
; 0x46E686ED

The Intel HEX record changes from the 14.4v firmware are:

-:107360009BE50700E2F92E00436E240098E5070034
+:107360009BE50700D26E2800636E240098E50700B5

-:102B60009BE50700E2F92E00436E240098E507007C
+:102B60009BE50700D26E2800636E240098E50700FD

I tested the patched firmware on my PL30 and it outputs 14.50v. I’ll attach/post the compiled .hex here in case anyone else wants the same fixed-voltage 14.5v firmware without doing the patch manually.

PL30_14_5_DSPIC33FJ64GS606_NoHWMod.zip