I like doing these early mock-up’s of PCB’s and adjust schematics because they tell me what I can achieve with pins and space. This is the new RPI Hub I am working on. The details will change, but it looks doable. 2 x RS485 2 x RS232 1 x TTL UART (consume a RS232 port…
I really like CubeMX for what it tries to do, but having used it for a while on different MCU’s I also realize that the code it generate is not very mature. On some MCU’s it works well, on others it don’t even compile or as in the example of STM32F105RB temporary brick the MCU.…
Updated Article! I am quite happy with the 5 port Com Hat I made for Raspberry PI, but I want to use a STM32F405RG and maximize usage of all it’s IO capabilities. This will be an upgraded Hat with a few more features included: Replace F105 with the faster and more capable F405 including 1Mb…
I am a heavy user of STM32F105RB/RC, but I have not used it much with SW4STM32 before. SW4STM32 (System Workbench for STM32) or ac6wb as it also is called is based on eclipse and uses OpenOCD to connect to the MCU’s Serial debugger. A few days ago while testing CANUSB I noticed problems. First on…
I have never used the STM32 Server or this link utility before because the IDE’s mostly do the job. But, I have discovered something strange… After flashing code on a STM32F105RB a few times from SW4STM32 the chip would not download anymore. It happened systematically on 5 different MCU’s, but after using this utility to…
This is the cost for a single unit from ST’s own site. Buy 1 million and you get 3.8USD, but you are still not close to the stated cost on their sides. And adding to this you get 20.- USD P&P and Customs and Handling fees. A single MCU would actually cost me ca 50.-…
Dealing with STM32F105RB I just had the strangest error. ST-Link started failing on my CANUSB adapter and as I tested on a Rx breakout it failed there to. Moving to F405 it works fine and moving to a 3rd board with F105 it works fine. Two different boards with the same MCU failing at the…
A trick I use is that I connect GND to the ground plane to avoid ground loops. But, what I need to watch out for is isolated icelands that is not connected. I realized that the EDA don’t check this, so I check it manually by using MSPaint to paint the ground plane. In this…
The illustration above show the number of connectors we could need on the Train Control System. I intend to use 1.25mm JST Micro connectors, but space is very limited so this will be a challenge. #1 is the 6 pin programmer port. It is no way to get the programmer with USB connection on the…
This is an early mockup of a ESP32 based adapter for Raspberry PI. I like this early mock-up’s because they give me an idea about what we can get away with. in this case I can add 3-4 connectors top-left to get some extra IO, but I will still have plenty of space. I need…