“LA104 is another nice piece of handheld hardware coming from e-design / miniware company similar to their previous product - pocket digital storage oscillosope DS203.
This time they designed wholly digital device without analog circuitry featuring 4 general purpose IO signals and 4 digital inputs processed by AG1K FPGA chip, the processor used is the same as in DS203 - STM32F103VCT6. Device is battery powered, charged through USB micro connector, its display (ILI9341) offers resolution of 320x240 pixels and the storage EEPROM has this time capacity of 8MB. Check the scheme here
Flashing is done by holding first function button during powering up and by copying firmware HEX file onto the virtual flash USB drive formatted as FAT12. This could be tricky, since this approach does not work on Mac OSX. For some reason the default copying procedure after mounting this USB drive on OSX is different than the programmers at e-design expected, it works reliably only on Windows machines. During extensive research and testing I found a method how to upload firmware on any unix/linux operating system. Just build tools/dfuload by running build.sh script and you are ready to flash new firmwares.
When I was developing alternative firmware for DS203, I was trying to design some simple operating system that would allow me to upload easily new programs to the devie with ability to switch between them without flashing it again. Something similar that jpa did before with his PAWN interpreter on DS203 with a little difference that the application will be native C/C++ compiled code offering full computational power of the device. Unfortunately the GCC toolchain I was using had some bug which produced ARM32 instructions in PLT section which are not supported by STM32F103 and I was not able to force the compiler to use Thumb instruction set. So the dynamic relocation of imported symbols was an impossible task to implement. Now after few years, this problem was fixed and finally I could continue developing this operating system I have started before.”