KLSTR.rdm

Use KLSTR.dev hardware

Modify a KLSTR.dev board so the KLSTR.nano's USB lines reach the USB-C receptacle, turning the board into a KLSTR.rdm development dongle.

A KLSTR.rdm is just a KLSTR.nano whose USB is broken out to a PC, so a KLSTR.dev board can stand in for the boxed product. Remove two 0Ω resistors, add two jumpers, and the board's USB-C receptacle reaches the nano. This page is that modification.

If you have not met the KLSTR.rdm hardware yet, read the KLSTR.rdm introduction first.

Using a KLSTR.rdm box (bonano)? No hardware modification is needed, its USB port is already wired to the nano. Go straight to the special firmware page.
Draft. The wiring image and the procedure are in place. The resistor designators are still marked TODO, so work from the image rather than from part numbers.

What you need

  • A KLSTR.dev board with a working KLSTR.nano.
  • A soldering iron suitable for desoldering small 0 Ω links
  • Two ordinary female to female jumper wires

Modify the board

On a stock KLSTR.dev board the nano's USB lines are not routed to the USB-C receptacle. Two changes fix that.

Remove the default 0 Ω resistors

The 0 Ω links hold the USB-C receptacle's data lines in their default assignment. Desolder them so the receptacle's data pins are free to be driven by the nano.

  • Work with the board unpowered and unplugged.
  • TODO: confirm the exact resistor designators to remove.
  • Keep the resistors if you want the option of reverting the board later.

Jumper the nano USB lines to the USB-C receptacle

Use the female to female jumper wires between the nano's USB pins and the receptacle side.

Cross the data lines. The + / - silkscreen on the larger 5/6 double pin header is not correct. Wiring D+ to D+ and D- to D- by the printed markings will not enumerate. Cross them, and check your wiring against the image below before you plug anything into a PC.

This image is the authoritative reference for the modification. The red lines are the jumpers to fit. Note that they cross. Also, the third red line conecting 2 pins on the board is an artifact of earlier KLSTR.dev harware revisions, upon which the KLSTR.one needed to be held in reset. This is no longer required and may be omitted.

With the resistors out and the jumpers crossed correctly, the nano is reachable over USB from a PC.

Check the nano is reachable

Plug the modified board into the PC with a USB-C cable before going any further. If the modification is good, two things follow.

  • The PC enumerates a new USB device. It turns up in Device Manager on Windows, in System Information → USB on macOS, or under lsusb on Linux. TODO: confirm the device name and the VID/PID the nano presents.
  • The device shows up in KLSTR.ctrl. This needs the usbNano build, the standard build does not talk to a nano over USB at all.
Showing up is not the same as being connectable. The nano still runs its normal fixture firmware at this point, so KLSTR.ctrl lists the device but will not offer to connect to it. That comes with the sniffer firmware, below.

If nothing appears on the PC at all, the crossed data lines are the first thing to re-check against the image above, then see Troubleshooting at the end of this page.

What next

The modified board is not a usable tool yet. Hardware was only the first of three requirements, and the other two are the pair of special builds:

  • On the nano, the sniffer build. Until it runs, the nano will not present itself to KLSTR.ctrl as a connectable USB device.
  • On the PC, the usbNano build of KLSTR.ctrl. Without it, KLSTR.ctrl never lists a USB nano in the first place.

Special firmware

Get both special builds: flash sniffer.klstr.nano onto the nano, and run the usbNano build of KLSTR.ctrl on the PC. Required for both the KLSTR.rdm box and a modified KLSTR.dev board.

Troubleshooting

SymptomMost likely cause
Nothing appears over USB after the modificationD+ / D- not crossed at the 5/6 double pin header, or the 0 Ω resistors are still fitted
The PC sees the board but KLSTR.ctrl does not list itWrong KLSTR.ctrl build. The usbNano build is required, the standard build never lists USB nanos
KLSTR.ctrl lists the board but never offers to connectExpected at this stage. The sniffer firmware is not flashed yet
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