MicroPython Forum (Archive)

Hello, I have a data logger using MicroPython 1.12 with a design based on the Pyboard 1.1. I have an external SPI ADC which is a LTC1857 as shown in the datasheet below where the SPI bus speed is set to 5Mbps. There are also other SPI devices on the same bus but this should not be relevant to the pr...

@chuckbook Thank you for the reply. I did try changing the default PRER value in the STM32 HAL file which should set it's default value on power up so I would have thought this should have changed the prescalar value? I noticed in the STM32 manual that the reset value is the same as the default valu...

Hello, I have a Pyboard V1.1 project using Micropython 1.12 where I would like to change the RTC sub-seconds from 4ms to 1ms. From the STM32 manual (RM0090) there is the 32,768 Hz RTC coming into the "RTC_PRER" register and by default this is set to 0x7f (127) giving an output frequency of 256Hz for...

After some more time was spent on this here is the solution to this problem which might help others. It was found that the operation that increases in time as the file size increases was the file opening as shown below: self.file = open(self.filePathLog, 'a') self.bytesWritten = self.file.write(data...

Hello, I have a data logger based on PyBoard 1.1 where files are written to the FAT32 SD card at a rate from 0.1s up to 24 hours in CSV format. What I have noticed when trying different ways to manage the logs files are the following: 1. If you create a new file say every minute, hour or day, is tha...

I am not sure what happened here with the routing, but I will see how the next board goes.

@ chrismas9
It is a 4 layer PCB with a power and GND plane so this should be fine?

Thank you for your comments and suggestions. I finally just found the issue (this is a part-time effort currently) which ended up being two tracks touching from the auto-routing as shown by the red arrow below: pcb-back (Small).JPG Unfortunately, I did not pick that up before sending the design off ...

I have been developing a data logger using MicroPython 1.12 and I am currently up to PCB revision 3. The first two revisions worked fine with the SD card and it mounted as normal when you plug the USB into a PC and I could see the SD card. The third revision of my PCB, the SD card is slightly furthe...

I would like to know how easy it is to reverse engineer Micropython bytecode (.mpy) vs Python bytecode (.pyc)? I have a product which I will need to supply updates in DFU format for the STM32 and while you can set fuses to prevent reading the flash memory on the STM32, I am interested to know how ea...

The problem ended up being the MCP23S17 chip has an IO-RESET pin which was not pulled high (resets on low). This meant that in deep sleep, the STM32 was no longer controlling this pin so it went low putting the chip into reset which was preventing PA0 from triggered the wake up interrupt. The fix wa...