Programming dsPIC33CK64MC105
from Raspberry Pi 4B on Debian 13

I'm a retired EE who has worked on analog, digital, ASIC & hardware and C, Perl & Python CAD software over my 40+ year career. I use a Raspberry Pi 4B running Debian 13 (trixie) Linux for CAD because it's fun and -- if I download software that causes problems with the system -- it's easy to swap in a backup SD and try something different. The Raspberry Pi 4B is an arm64 computer, not an amd64 computer, though, and, when I tried using a QEMU x86_64 Linux instance to run Microchip's MPLAB X IDE, it took hours to load & and hours trying to start the IDE before I gave up and asked Claude.ai for help. duck.ai allows you to run Claude Haiku 3.6 and I was happy with that. However, I found that using a free Claude.ai account and running Sonnet 4.6 was a better choice for this project. Claude.ai summarizes the problems we found & it (with a little help from me) fixed below:

Microchip's XC compiler toolchain can be compiled and run on a Raspberry Pi 4B running Debian 13 (Trixie). The missing piece was a way to download the compiled .hex file into a Curiosity Nano dsPIC33CK64MC105 evaluation board — without needing a full x86 MPLAB X installation.

Microchip provides pymcuprog, an open-source Python programming tool that supports nEDBG-based Curiosity Nano boards via the EDBG/CMSIS-DAP protocol. On paper this should work natively on ARM Linux. In practice, four distinct problems blocked it.

Install pymcuprog and pyedbglib

$ pip install pymcuprog pyedbglib --break-system-packages

Download the dsPIC33CK Device Family Pack

Download Microchip.dsPIC33CK-MC_DFP from packs.download.microchip.com and extract it. The relevant directory is the versioned subfolder — in this example, version 1.8.299.

$ mkdir -p ~/microchip/packs
$ cd ~/microchip/packs
$ # Extract your downloaded .atpack file (it's a zip)
$ unzip Microchip.dsPIC33CK-MC_DFP.1.8.299.atpack -d dsPIC33CK-MC_DFP/1.8.299

$ # Verify the scripts directory exists for your device
$ ls ~/microchip/packs/dsPIC33CK-MC_DFP/1.8.299/scripts/dspic33ck64mc105/
nedbg_dspic33ck64mc105.py  dspic33ck64mc105pds.py  version.py  common/

The Curiosity Nano nEDBG is a composite USB device presenting four interfaces: HID (CMSIS-DAP), CDC-ACM (serial), Mass Storage, and DGI. Linux needs permission rules to make the HID interface accessible to non-root users.

Create the udev rule

# Microchip / Atmel nEDBG (Curiosity Nano onboard programmer)
# VID 03eb = Atmel (used by nEDBG even on post-acquisition boards)

SUBSYSTEM=="usb",    ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="2175", MODE="0666", GROUP="plugdev"
SUBSYSTEM=="hidraw", ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="2175", MODE="0666", GROUP="plugdev"
SUBSYSTEM=="tty",    ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="2175", MODE="0666", GROUP="plugdev"
SUBSYSTEM=="block",  ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="2175", ENV{UDISKS_IGNORE}="1", ENV{UDISKS_AUTO}="0"

$ sudo udevadm control --reload-rules
$ # Unplug and replug the Curiosity Nano, then verify:
$ ls -la /dev/hidraw* /dev/ttyACM*
crw-rw-rw-+ 1 root plugdev 242, 3 Feb 26 16:02 /dev/hidraw3
crw-rw-rw-+ 1 root plugdev 166, 0 Feb 26 16:02 /dev/ttyACM0

Verify the device is enumerated correctly

$ lsusb | grep 03eb
Bus 001 Device 006: ID 03eb:2175 Atmel Corp. nEDBG CMSIS-DAP

$ python3 -c "import hid; [print(d) for d in hid.enumerate() if d['vendor_id']==0x03eb]"
{'vendor_id': 1003, 'product_id': 8565, 'serial_number': 'MC020023603FAS001511',
 'manufacturer_string': 'Microchip Technology Incorporated',
 'product_string': 'nEDBG CMSIS-DAP', ...}

This is the most counterintuitive part. pymcuprog's --packpath argument must point to the device-specific scripts directory inside the DFP, not the top-level version directory.

Internally, nvmpic.py does this:

sys.path = [os.path.normpath(packpath)] + sys.path
sys.path = [os.path.normpath(packpath + "//common")] + sys.path
from common.debugprovider import provide_debugger_model

For the import to succeed, packpath must be the directory that directly contains the common/ subdirectory and the dspic33ck64mc105pds.py file.

# ✗ WRONG — points to DFP version root
--packpath ~/microchip/packs/dsPIC33CK-MC_DFP/1.8.299

# ✓ CORRECT — points to device scripts directory
--packpath ~/microchip/packs/dsPIC33CK-MC_DFP/1.8.299/scripts/dspic33ck64mc105

Convenience wrapper script

Save typing with a small shell wrapper:

#!/bin/bash
PACKPATH=~/microchip/packs/dsPIC33CK-MC_DFP/1.8.299/scripts/dspic33ck64mc105
pymcuprog -t nedbg --packpath $PACKPATH -d dspic33ck64mc105 "$@"

$ chmod +x ~/bin/picprog

Ping — verify connection

$ picprog ping
Connecting to any nedbg
Connected to nEDBG CMSIS-DAP from Microchip (serial number MC020023603FAS001511)
Debugger firmware version 1.30.35
Debugger hardware revision 0
Device mounted: 'dspic33ck64mc105'
Pinging device...
Ping response: 9912
Done.

Write a hex file

$ picprog write -m flash -f myprogram.hex --verify

Read flash memory

$ picprog read -m flash

Erase the device

$ picprog erase

Write with erase first (typical programming flow)

$ picprog erase && picprog write -m flash -f myprogram.hex --verify

• 01

  Shut down any QEMU instance that has USB forwarding to the Curiosity Nano. QEMU takes exclusive ownership of the USB device and prevents any other process from opening it. This also causes repeated USB resets visible in dmesg.

• 02

  Install pymcuprog and pyedbglib via pip. The nEDBG's Atmel VID 0x03EB is already handled correctly in pyedbglib/hidtransport/cyhidapi.py — no source patching needed.

• 03

  Create /etc/udev/rules.d/99-microchip.rules with rules for both SUBSYSTEM=="usb" and SUBSYSTEM=="hidraw" matching ATTRS{idVendor}=="03eb". The hidraw rule is essential — hidapi opens /dev/hidrawX, not the raw USB device.

• 04

  Download the dsPIC33CK-MC_DFP device pack from packs.download.microchip.com and extract it. Confirm the scripts/dspic33ck64mc105/ directory exists inside the version folder.

• 05

  Pass the device scripts directory as --packpath, not the top-level DFP directory. The correct path ends in .../scripts/dspic33ck64mc105. pymcuprog prepends this to sys.path to import the common module directly.

• 06

  Verify with pymcuprog ping. A successful response shows Ping response: 9912 — the device ID for the dsPIC33CK64MC105 is 0x26B8 = 9912 decimal.