When conio was implemented for the osic1p target, the cbm
target was used as a blueprint. But it was overlooked that the
cbm target encodes CR as 0x0A and LF as 0x0D, while the
osic1p target uses the ASCII encoding of CR and LF. Therefore
conio output of '\n' moved the active position to the start of the
line and '\r' moved the active position to the next line.
This change implements the correct semantics of '\n' and '\r'
in conio for the osic1p target.
Fixes#1747.
Restructured according to review in pull request #567.
The "inputc" function was moved in slightly modified form
to kbhit.s and replaces the old keyboard scanner.
cgetc() uses the new kbhit() to read a character.
About all CONIO functions offering a <...>xy variant call
popa
_gotoxy
By providing an internal gotoxy variant that starts with a popa all those CONIO function can be shortened by 3 bytes. As soon as program calls more than one CONIO function this means an overall code size reduction.
The name RAM doesn't make much sense in general for a memeory area because i.e. the zero page is for sure RAM but is not part of the memory area named RAM.
For disk based targets it makes sense to put the disk file more into focus and here MAIN means the main part of the file - in contrast to some header.
Only for ROM based targets the name RAM is kept as it makes sense to focus on the difference between RAM and ROM.
The way we want to use the INITBSS segment - and especially the fact that it won't have the type bss on all ROM based targets - means that the name INITBSS is misleading. After all INIT is the best name from my perspective as it serves several purposes and therefore needs a rather generic name.
Unfortunately this means that the current INIT segment needs to be renamed too. Looking for a short (ideally 4 letter) name I came up with ONCE as it contains all code (and data) accessed only once during initialization.
Experiments show that under BASIC by default
25 rows by 24 columns are used. 24 columns is
also the width that is fully displayed on a real
C1P on the monitor. conio now matches that now.
If kbhit() detects that a key is pressed, it fetches and
buffers the character. If cgetc() detects a buffered character,
this one is returned instead of fetching one with the PROM
routine.
Adjusted comment formatting in several assembler files.
Removed dummy kbhit() function, as it's better to get a linker
error than an implementation that does the wrong thing.