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RE: Low-Power Wireless: Building an Outdoor Transmitter!

shabaz — Wed, 02 Sep 2026 20:44:16 GMT

Regarding the issue that reset would not automatically occur after programming, I just tried this mod:

Basically, Q1 was the PNP transistor, that's been replaced with the P-ch MOSFET, and R7 upped to 100k, and added C22 in series with R6, but also shunted that with a 1 Mohm resistor.

The idea was to make the BSL_INVOKE line go high only briefly, rather than keep it held high during programming, therefore allowing the microcontroller to reset at the end of programming, without going back into bootloader mode.

It does work, but I don't know how reliable it will be.

Here is what I see on the Q1 gate (yellow) and Q1 source (red), when the mspm0_programmer.py is started.

This shows the Q1 gate again, and the BSL_INVOKE line (red). Nice pulse I guess.

The screenshot below shows Q1 gate again (yellow), and the MSPM0 *RST line (red). Not happy it is going to 4V. I believe a fix for that could be to add a diode in series with the *RST line, so the CH340K can only pull it low. I still need to try that.

The multiple pulses are probably because the programmer code enables and disables the *DTR and *RTS lines a few times at the beginning, it seems to be a driver thing (I didn't get reliable results in the past without that). Whether all this works with (say) Linux/Mac, and on different speed PCs, I have no idea!

In summary: With this mod, I can program the MSPM0, and have it restart automatically, all under control of the USB, no boot or reset buttons need to be pressed. And I can access the user menu using TeraTerm, provided it is set up as shown below (see the DTR setting) again just under USB control, no button-press etc. But with that caveat, that this might not work for all setups.

RE: Low-Power Wireless: Building an Outdoor Transmitter!

shabaz — Tue, 01 Sep 2026 21:44:39 GMT

I made two of the outdoor transmitters, one will be a test unit, so I put that in an enclosure before I accidentally damage the delicate antenna.

If I had thought things through properly, I'd have made the PCB shorter, so I could have put the antenna on the end panel (at least 5 mm of clearance is needed from any ground plane).

By chance I had some light pipes, they make quite a visual improvement rather than peeking down the LED holes. Red indicates the CC1101 is powered up, and the blue flickers on when transmitting.

RE: MSPM0 sample photodiode with internal OpAmp and ADC

DAB — Sat, 15 Aug 2026 22:01:54 GMT

Very cool Jan.

RE: MSPM0 OpAmp interconnection schematic

DAB — Sat, 15 Aug 2026 21:57:03 GMT

I like it.

They are clearly looking at the PSOC for inspiration.

RE: MSPM0 OpAmp interconnection schematic

shabaz — Fri, 14 Aug 2026 16:47:31 GMT

Nice, those two op-amps look very flexible.

It's great how the initial config is just a matter of using a graphical tool (can be local or browser-based). Screenshot below in case anyone's not seen what that looks like.

Personally I really like how the generated code is specific to certain files that never need touching, whereas other microcontroller development environments generate code interspersed into the main code.

RE: MSPM0 sample photodiode with internal OpAmp and ADC

Jan Cumps — Fri, 14 Aug 2026 11:41:26 GMT

Horowitz and Hill cover this in Art of Electronics:

^{image source: my physical copy - fair use}

interesting: they released the Transimpedance Amplifiers section of their X-Chapters book as a sample: example chapters

RE: August 12th eclipse: can I measure it?

Jan Cumps — Fri, 14 Aug 2026 08:30:58 GMT

An explanation of the design: [mention:1d6f895123284895aaf8ae634902ac9b:f7d226abd59f475c9d224a79e3f0ec07]

RE: August 12th eclipse: can I measure it?

Jan Cumps — Wed, 12 Aug 2026 19:40:35 GMT

Some early results and photos:

RE: August 12th eclipse: can I measure it?

Jan Cumps — Tue, 11 Aug 2026 18:53:36 GMT

Ready:

I'll be using putty to log output to a text file

RE: Building a Local IoT Controller for a NetFlame Stove

vmate — Wed, 22 Jul 2026 17:51:18 GMT

You might want to look into Cage, it lets you run a single application in full screen, with no other distractions or extra load on your hardware.

RE: Hardware hacking Della Mini Split aircon unit

agranted — Mon, 29 Jun 2026 01:58:26 GMT

Another year passed, a cross country move (including moving my Della), and a reinstall of the minisplit I was able to revisit this. I'm happy to say I've got a stable ESPHome build running on the SWLF-01 with a Della 048-MS (https://github.com/adamgranted/esphome-della-ac)

The 048 utilizes the AUX OEM protocol with what appears to be minor frame variations between models. At this point the firmware is 100% fully featured for the 048 and will soon have support for the Della Motto 12K1VRH-20S-JA-I+O.

Some HA screenshots:

[mention:82dcf05dbddf4b99ae060c6cdfaacf4e:e9ed411860ed4f2ba0265705b8793d05] [mention:44f3532346b84c1f84822aa07b854f87:e9ed411860ed4f2ba0265705b8793d05] [mention:ebd4f071a8154174bf94f5c9f4289fab:e9ed411860ed4f2ba0265705b8793d05]

RE: ASCII Aquarium Turns CYD Into a Tiny Interactive Fish Tank for Your Desk

kmikemoo — Fri, 29 May 2026 19:00:22 GMT

This is AWESOME! [emoticon:d6dd260102fd406884fc96b8bc59760b] There's a CYD version?! I'm bookmarking this. Maybe I'll make some time for it. [emoticon:752f32bcc91d4a448db162742a877a4a][emoticon:1435ff2429184e17bc948e4f19178e1e]

RE: Hardware hacking Della Mini Split aircon unit

SmellyDwarf — Thu, 11 Dec 2025 22:15:22 GMT

Hey um, I might have something specific that could possibly help with this entire process. I have the direct email of the coder who writes the Della app, I'm also usually pretty good at talking to people, but if you guys wanted I could probably try to get some useful info out of him, or possibly ask about getting the app getting a means of localized LAN control (sort of like what Govee offers).

Let me know, I joined specifically because of this post.

RE: A Comprehensive Guide to LoRa Modules

HKPhysicist — Mon, 06 Oct 2025 16:53:56 GMT

Microchip has opened their RN series LoraWAN chips and stacks in their Github.

If you like their MPLAB X IDE and PIC 8 bit, look no further. What you need are there.

https://github.com/MicrochipTech/RN2xx3_LORAWAN_FIRMWARE

With Microchip's highest quality hardware and firmware, it can't be wrong. [emoticon:fbd079a1c4f748c5a234faee215de9cc]

RE: Low-Cost LoRaWAN Gateways!

HKPhysicist — Mon, 06 Oct 2025 16:44:02 GMT

2 years have passed, what are the cheapest out-of-box LoraWAN stack internet gateways?

I want to develop my own LoraWAN sensor nodes and integrate all of these into my own cloud service provider.