[Amforth] A RISC-V update

[<ho...@tj...>]

A risc-v update for CH32V307

AmForth-RV can now compile to flash directly rather than saving a word 
already compiled in ram as before. This is better and much more like the 
approach taken by the AVR code base. However, it does need an mcu that 
is able to do this. The flag field in the dictionary is used more, which 
simplifies and optionally declutters word listings. I think this was 
something that was intended, but not fully implemented. Being able to 
call C library functions from Forth has helped with beginning to add 
IEEE-754 floating point to AmForth-RV. There is a link to a pre-built 
hex file on [1] and the development board seems to be available in the 
EU from [2]. More details in the project logs [3].

Best wishes,
Tristan

[1] https://tjnw.co.uk/amforth-rv/pages/building.html
[2] 
https://www.elektor.com/products/wch-ch32v307v-evt-r1-risc-v-development-board
[3] https://tjnw.co.uk/amforth-rv/pages/logs.html