Until recently, I also thought that assembly routines could only be implemented in the PASCAL environment. It is by pure luck that I read the description of the WRITEIO command in the BASIC 5.1 manual. It is interesting to note that the facility to call assembly program is not available in lower revision BASICs like 4.0, 3.0, 2.0. It looks like HP decided to add this feature at that time for some reason... maybe because the Mac / Amiga were showing very fast programs/demos and the HP was beginning to look bad in comparison ?
I was not aware of the third party assembler. Would it run on Series 200 with basic 5.1 ? Can you provide a pointer where I could download it ?
I have a few ideas of how to better understand the behavior of my program. I will post my findings here.