The 2 blue signals crossing the bigger, red Power lane is asking for trouble. The blue lanes are 0-3V ADC signals, while the power lane is feeding PWM MOSFET’s. What will happen is that PWM noise from current spikes will jump over to ADC signals and create a false current signature. But, I believe it…
I must admit that sourcing for STM32F405RG is an issue. I have bought batches from China and I am rejecting a lot of MCU’s. The worst is actually the time to solder them on before I can test, so I seriously need the tester shown in my last article. This is worst as I like…
Finally – I just discovered test boards with sockets for STM32 LQFP64 and LQFP100. They are a bit pricy – ca 65.- USD yet, but it is a start. These are on the list of things I planned to make because I could not buy them.
I currently plan using INA194 that have a 50x gain. As our max voltage in is 3.3V this means the max voltage over the shunt need to be 3.3/50= 66mV. Given a max current of 2.5A that gives a Shunt resistor R = V/A = 0.066/2.5 = 0,0264 R or 25mOhm. Now – 2.5A over…
Left side of the 3-Phase/Stepper/PWM Hat done. This is the hardest bit, but it went much easier this time because the previous attempts gave some hints and lessons learned. I am far from finished, but it is not hopeless. My main concern is the ground-plane getting to fragmented and unable to support the currents –…
I am returning to this board to make a new attempt because it is a very attractive board to make + I just received another bunch of DR8313 chips and Connectors that I need to use for something. What stalled me on the last attempt was several issues: 12 x current sensors are a bit…
Baudrates like 110, 300, 600, 1200, 2400, 4800, 9600, 14400, 19200, 38400, 57600, 115200, 230400, 460800, 921600 are rather standard, but what do you use to set 10Mbps? Testing with a Windows PC I manage to get 2Mbps as shown here, but Windows is not able to open higher frequencies. I am in this case…
I have not tested everything yet, but rev 1.1 of XPortHub need a few changes: correct package on serial flash. wap sequence on dip switch. replace battery with a proper battery holder. Can be mounted on back-side if needed. This also fix the short-cut here. Test Power Connector. I have a 2-pin connector that is…
This was a rare bug on the XPortHub! I have not bothered to test the super-cap/battery for the VBAT much, but suddenly realized as I was doing other changes that I had an error message related to this. And correct – measuring the PCB I have a self infected short-cut. CNC machinery making PCB’s require…
FATFS is a middleware component you can add to create a MicroSD API with full file I/O support. It only takes a few clicks with CubeMX and you have an API with the following and more: f_mount(): Register/Unregister a work area f_open(): Open/Create a file f_close(): Close a file f_read(): Read a file f_write(): Write…