Changes
/* Cross Development */
[[Category:Source code]]
== General Notes ==
* Memory range for programs is &0040-&a700. This avoids firmware and memory allocated by AMSDOS disc ROM.
* Basic programs start at &170.
* Firmware uses interrupt mode 1 of the Z80 (interrupts jump to &0038)
* Lowest place you can *LOAD* a binary file to with BASIC is &389 e.g.:
openout"d"
memory <address>-1
closeout
load "code",<address>
call <exec>
*Screen is normally at &c000-&ffff.
*Stack is normally at &c000 and goes down.
*Extra registers (BC', AF', HL', DE' are reserved by the firmware). Avoid if you are using firmware functions.
*Lower rom (containing OS) can be paged into memory between &0000-&3fff.
*Upper rom is selectable, examples are BASIC and AMSDOS. They can be paged into memory between &c000-&ffff.
*From basic, a game is run with:
RUN"<filename>
keep it in the safe memory ranges and it'll run from cassette and disc.
*Screen is normally 40 crtc chars wide (CRTC R1=40), 25 crtc chars tall (CRTC R6=25). 8 scan lines per char (R9=7). Firmware functions assume this.
*Screen is bitmapped. You must draw/erase your own sprites and text.
