DC2N5-LC DIY kits available again

It’s been a long while, almost 3 years now, since I sold the last DC2N5-LC DIY kit. I am glad to confirm that kits are available again and I am going to also build a single fully cased device.

DC2N5-LC running the latest firmware version

A fully built DC2N5-LC as seen from the tape port edge

For the details and costs, check my sales page.

More surprises with STM32 micro-controllers

It turns out that the STM32 micro-controllers I bought a few weeks ago (in order to replace the ones on “Blue pill” boards that can’t run firmware built for the STM32F103C8T6 micro-controller) are, in fact, re-branded CS32F103CBT6 micro-controllers.

Re-branded CKS32F103CBT6 micro-controller

The funny thing is that my ST-LINK v2 programmer/debugger clone uses a genuine CKS32 micro-controller (without re-branding):

Genuine CKS32F103C8T6 micro-controller

Given the fact re-branded CKS32F103CBT6 micro-controllers run the DC2N5-LC firmware without issues, and have twice the flash memory compared to the STM32F103C8T6 micro-controller originally used in “Blue pill” modules, I would have been quite happy if I were sold “Blue pills” with the CKS32F103CBT6 micro-controller, even without re-branding!

If I can source a few more CKS32F103CBT6 micro-controllers, I will keep going with replacing the micro-controller of unsuitable “Blue pill” boards and enjoy 128kB of flash memory, which might allow me to include a JPEG decompressor in the DC2N5-LC firmware too. Such decompressor is already part of the DC2N5 firmware that runs on NXP micro-controllers.

Unfortunately, such “upgrade” will not be available to end users as I don’t feel it’s ethically correct to provide them with “Blue pills” whose micro-controller has been replaced by myself manually.
It might be the case that I end up being able to reliably source “Blue pills” with genuine CKS32F103CBT6 micro-controllers (perhaps from AliExpress), but I doubt there would be enough demand for new DC2N5-LC units to distribute a variant with 128 kB of flash memory.

Stay tuned!

Yet another new feature in DC2N5-LC

Yet another change request was implemented in the DC2N5-LC firmware: users can now select the output folder for all dumping operations 🙂

New option in the DC2N5-LC firmware

Stay tuned!

STM32 decapping results

As announced in a previous post, one of the STM32 micro-controllers from a “Blue pill” batch that I bought recently was sent to Finland for decapping.

Well, Tommi received it, decapped it and took the following picture:

Counterfeit STM32 micro-controller

This is clearly a CKS32 die as already seen and documented here and here.

Unfortunately, this version of the die doesn’t seem to be able to run code built for STM32F103C8T6, so all the boards are useless to me unless their MCU is replaced.

New feature in DC2N5-LC

As requested by Rixa, the DC2N5-LC monitoring option now also lets users choose capture mode 🙂

DC2N5-LC monitoring mode lets users choose capture mode

Stay tuned for more!

Yet another batch of blue pills with counterfeit MCU

Today I received another batch of 20 blue pill boards, and what do you know? The MCU is another fake.

This time the fact the MCU is counterfeit can be easily spotted: The font used is too narrow, the first line reads STM32F instead of STM32, the orientation hole is bigger and too smooth, the ST logo is quite different, and the plastic surface has got bubbles in it.

Yet another counterfeit STM32 MCU on a blue pill

What a disgrace.

DC2N5-LC teaser video

I think the new version of the DC2N5-LC firmware is coming along quite nicely 🙂

Stay tuned for more!

STM32F10C8T6 module fixed after installing a genuine MCU

As I had received a handful STM32 MCUs, I managed to solder one on the “blue pill” board from which I had desoldered a fake/defective one.

STM32 MCU after I finished soldering it

The new MCU seems to be working fine, having tested the DC2N5-LC firmware with it: access to the display and SD card was OK and dumping tapes worked fine too (I tested this 6 times in total to be on the safe side) 🙂

Blue pill board running the DC2N5-LC firmware after an MCU replacement

Obviously, having gone through some substantial maintenance, I won’t be selling this device to anyone: it will become part of my own pool of spare devices.

In about 4 days I will get in touch with an eBay representative and state my case about the STM32F103C8T6 modules I had bought, pointing them to these results.

More shenanigans from the East

I had ordered a few STM32 MCUs to try and replace a few of the ones that are on the blue pill boards that are not working. Well, today I received such MCUs but I reckon they are in a not quite ideal state:

The STM32 micro-controllers I had ordered

It’s not that the MCUs can’t be used, but heck, here’s the item picture from the eBay listing I bough them from:

Image from the eBay listing for STM32 micro-controllers

Tiny MCUs like these usually ship in plastic tape so that:

1. they don’t get damaged and
2. pick’n’place machines can be efficiently loaded with them

Dealing with Chinese sellers on eBay has rarely been this frustrating…

Quite a satisfying result for the day

I finally got the time to desolder the MCU from one of the STM32F103C8T6 boards I recently received. Here’s what the board looks like after the operation:

STM32F103C8T6 module without its micro-controller

The MCU will soon be on its way to Finland for de-capping, which will reveal its provenance, possibly based on text on the die itself.

Worst case scenario: the die is a genuine one from STM but either from a defective batch or damaged somehow after manufacturing. That is a possibility, although the MCU looks suspiciously fake, starting from the color (black rather than dark grey) and finish of the plastic case (gloss rather than matt), smaller fonts used for marking the chip, engraving instead of printing of such markings.

I also managed to build another special edition DC2N4-LC device for myself, the white one pictured below, which joins the translucent blue one I built a few days back:

DC2N4-LC special editions

Stay tuned for more news!