Hi,
me and a friend have designed a custom open sourced smoothie control board for desktop cnc machines. Our design is still based around the LPC1769 but we have made some changes for cnc use.
We have successfully downloaded the sd bootloader and can see it is executing the bootloader code as the four status LEDs turn on and can see a temporary clock signal on the sd clock pin as the bootloader code goes through the SDCard_init() routine. However the firmware.bin file on the sd card doesn’t get read?
The sd cards that we have been using are fat32 that have been tested with Chinese AZSMZ mini 2.1 boards and they work fine.
We have reflashed these boards aswell with the smoothie bootloader via flash magic just to get a bit of practice before getting to our board. We have reflashed these boards using the following process
- Put LPC1768 into ISP mode
- Read device signature and check its correct
- Erase flash used by bootloader
- flash bootloader
and this has worked, it powers up and waits for the SD card to wake up and then downloads the firmware.bin file which i can see because status LEDs, continuous presence of a clock signal on the sd clock line and the code turns the rc oscillator off and uses the external crystal oscillator.
To make sure that the firmware had been erased from the microcontroller before programming I reset the board to see if anything would run and it didn’t so it had been wiped.
The next try on another board didn’t turn out as well
* Put LPC1768 into ISP mode
- Read device signature and check its correct
- Forget to erase flash used by bootloader
- flash bootloader
after resetting we get similar results to that of our board, that of there being a short clock pulse on the sd card clock line, the four status LEDs are on full and no clock pulse on the crystal oscillator so it’s not getting very far into the bootloader program for some reason? Also I made sure that when flashing our board that I had the correct microcontroller selected.
If anybody might have some thoughts on what might be happening or may have encounted the same problem I would appreciate some help
cheers
Imported from wikidot