BS1 / PICAXE Emulator
hippy
Posts: 1,981
An 80MHz BS1 / PICAXE with TV output ( NTSC and PAL ), USB input/output and speech synthesis.
Not quite ... Written in Spin so nowhere near as fast as it could be. Downloaded code isn't currently saved back to Eeprom, speech synthesis isn't there yet, but virtually all the core BS1 / PICAXE commands have been implemented. It's in a good enough state to be released as a sneak preview. Check the included .PDF for details of the extensions added.
Needs a Proto Board or Demo Board with 5MHz crystal. If using a PropPlug, PropClip or USB2SER, you need to disconnect the RESET line for this version. I just added an extra four pin header to my Proto Board and left that line not connected. The PropBS1.eeprom has to be (F11) burnt to Eeprom.
Simply use Parallax's Stamp Editor or Revolution Education Limited's Programming Editor to compile and download the target program. P0-P7 are the main I/O for BS1/08M, the inputs for 18X with P16-P23 as Pin0-Pin7 outputs.
No source code included because I'm working through IP issues.
Not quite ... Written in Spin so nowhere near as fast as it could be. Downloaded code isn't currently saved back to Eeprom, speech synthesis isn't there yet, but virtually all the core BS1 / PICAXE commands have been implemented. It's in a good enough state to be released as a sneak preview. Check the included .PDF for details of the extensions added.
Needs a Proto Board or Demo Board with 5MHz crystal. If using a PropPlug, PropClip or USB2SER, you need to disconnect the RESET line for this version. I just added an extra four pin header to my Proto Board and left that line not connected. The PropBS1.eeprom has to be (F11) burnt to Eeprom.
Simply use Parallax's Stamp Editor or Revolution Education Limited's Programming Editor to compile and download the target program. P0-P7 are the main I/O for BS1/08M, the inputs for 18X with P16-P23 as Pin0-Pin7 outputs.
No source code included because I'm working through IP issues.
zip
98K
Comments
I can't wait for the source to be released (that is, if Parallax and Rev allow it to be). I would love to see ethernet support (imagine PINK / Siteplayer + BS1 emulation).
Post Edited (Harrison.) : 9/29/2007 10:15:34 PM GMT
I got into decoding the object code generated for the BS1 and then discovered Chuck McManis's efforts along the same lines. That gave me a leg-up, confirmed what I'd discovered, filled in the gaps, and I was able to go further and unravel the bits he hadn't touched on. I created a disassembler and a compiler, and not having a BS1 ( too expensive for me ) I was actively looking into writing an interpreter from scratch on a PICmicro.
Then the PICAXE came along, I adopted that, and it turned out to be a super-set of the work I'd already done. As the PICAXE range has grown I've kept up to date with the various object code changes. The three .eeproms are all the same bar one byte and can switch instruction sets under user control but that makes no sense until I actual do store downloads in Eeprom.
I've been considering writing my own language-compiler-interpreter for a long time ( 4-bit chunks I calculated gave a good balance between code density and decoding speed ), then just as that started to look feasible and profitable with Microchip's newer processors with on-chip USB and a neat Ethernet solution, up pops the Propeller which threw a major spanner in the works