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Mon, 20 Apr 2026 00:00:00 +0000

Using hugo to build this site.

Buildroot, Linkstar, and Alpine

Mon, 20 Apr 2026 00:00:00 +0000

Progress has also been made to get the Hinlink/Linkstar H68K to compile and run under other distributions. Notably:

We’ve been able to formulate a build recipe for the Linkstar under buildroot;
The resulting kernel and supporting files will run as-is on the Linkstar, but with limited functionality, as buildroot is a bare-bones “distro” only;
Those bones though can be combined with some flesh from Alpine Linux to make a “frankenDistro”; namely, the boot code, kernel, and supporting files can be combined, carefully, with Alpine Linux to have a more fully-featured system.

Next Steps:

Once buildroot is updated to use U-Boot from 2026.04 or later (which has migrated the Linkstar dts files from Linux 6.18.X into it), we’ll submit a pull request to buildroot to incorporate the build recipe into the tree;
Once Alpine Linux begins using U-Boot 2026.04 in their ARM64 distributions, the Linkstar should be fully supported by that distro. We’ll check that out when the time comes.

Misadventures in Microprocessor Cloning

Mon, 20 Apr 2026 00:00:00 +0000

I recently purchased an electronics kit to build a component tester (capacitors, resistors, diodes, transistors and inductors). While putting it together, I experienced issues installing the ATMEGA 328p chip into its socket, breaking off one of the 28 leads. Half-luckily, that broken lead (pin 28) didn’t seem to impact the main function of the board, although it may be responsible in part for giving bogus low-battery warnings.

I bought the board on clearance sale; it has been discontinued by the manufacturer for some time. And the manufacturer’s support site wasn’t great; I had to contact them to remove an IP-Geo block to North America so I could download the assembly and usage manuals. So figuring getting a replacement part was unlikely, and with the source code not available, I came up with the bright idea to try cloning the programming to a new 328p; they are still reasonably easy to get at about $2.50 each.

First step on this journey was to get an in-system programmer (ISP) for the ATMEGA to copy off the code from the bunged-up chip and put it on a new chip. It took some trial and error to hit on the right combination of programmer and target arrangement to get this to work for me. I tried putting the target on a breadboard and using a TinyUSBisp (from HiLetgo via Amazon.com) as the programmer. Avrdude was able to access the TinyUSBisp programmer, but reading the contents of the chip off the breadboard was problematic (note I also used some pre-programmed ATMEGA 328p chips from Arduino Uno and clones to try and work out the methodology). This was using the simplest possible wiring from the programmer to the chip, without an external crystal, resistors, capacitors, etc.

Next attempts were at using an Arduino Uno instead of the TinyUSBisp as the programmer, with the chip again on a breadboard. I tried various wiring arrangements, with and without a 16MHZ crystal, resistors, and capacitors. This also didn’t work well (but later I noticed that I used a very wrong pair of capacitance values).

What worked best for me was using the TinyUSBisp as the programmer, and wiring it up to an Arduino Uno from which the usual 328p chip was swapped out for the target chip. This generally worked; I was able to read and write to practice chips fine. Initially, reading the flash from the chip with the missing leg seemed to work fine; but on further inspection, I discovered the lock bits were set, and so all the chip would give up to avrdude for the flash data were a bunch of 0xFFs; avrdude does not raise an error if the lock bits are set, it just won’t work correctly.

So I did what I could to make the damaged chip run as well as possible in the component tester kit.

And next time I need to program a 328p, I’ll probably start with the TinyUSBisp -> Arduino, but will give the breadboard arrangement, with the right capacitors this time, a try.

Update on OpenWRT for Hinlink/Linkstar

Sun, 04 Jan 2026 00:00:00 +0000

Jan 2026 Update #

Recently, the mainline Linux kernel (v6.18) has included the needed support for the HinLink/LinkStar H66 and H68 boards.

As downstream sites start integrating this new kernel into their projects and distributions, these small travel routers should gain more support. Alpine Linux recently included v6.18 in most of their products (not including Raspberry Pi currently).

Trying out the Alpine distribution for the LinkStar H68K is on my to-do list; higher up though is getting it included into the mainline OpenWRT distribution.

There are a couple of pull requests at this writing seeking to do that; one of mine (21015) and another person’s (21270). They have received some preliminary review by the site developers and code custodians, with more hopefully coming soon.

OpenWRT Development

Mon, 28 Jul 2025 00:00:00 +0000

Working on supporting the LinkStar H68K-1432v1 travel router in OpenWRT and Linux.