Arduino UNO R4 WIFI board

[mkobetic]

Getting AmForth running on Arduino UNO R4 board. A lot of things are still broken, but the basic system is running.

• realigned all the arm apps: same structure, amforth.asm, ...
• appl/launchpad-arm running under QEMU a debuggable
• appl/linux-arm running under Docker (not debuggable)
• appl/unor4 running on UNO R4 WIFI (delays, led, usart, at-usart(wip))
• gdb extensions for ARM debugging

Known problems:

• some basic words are broken e.g. / (need to run core test suite to fish issue out)
• variables are broken (need to separate DP and HERE - see branch rampool)
• values are not persisted (need to back them up with dataflash)
• user defined words are not persistent (need to implement saving to flash)
• undoubtedly a lot more to do ...