This rather boring drawing represent my new base for a Hat. Notice that I have removed the addressing scheme from the old ones, added USB and CAN as standard as well as Raspberry PI Hat form and SPI to communicate with the PI. F405 is so fast that we can use higher SPI speed (ca…
A bit different picture this time. This show the component layout and the green lines are the PCB lanes I need to make. I have added the package for the Micro SD Card holder, but I still only use 1.27 pitch headers for the Micro JST connectors. GPIO Header is not wired in schematics yet.…
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…