Haemogoblin wrote:Hi guys
I'm still messing about with my QL, actually been struggling to find software to run on it. If it wasn't for Dilwyn's site I'd be snookered.
I found a game called CBzone which acts a little odd via QPC2 and even worse on my actual QL. Is this designed for an expanded QL or something?
Cheers
CBZone was ported from another computer in 1995, so was written well before QPC2 came about.
Its manual (it was written by Timothy J West and his contact details at the time are in the README_QL file) doesn't explicitly say it doesn't run on unexpanded memory systems, just that it would run on Gold Card (slowly) and Super Gold Card, but might struggle (or in the author's words "unplayable") on Trump Card and older memory expansions.
There are some general suggestions for getting these older (i.e. pre-QPC2) games ot work on QPC2:
Start the emulator in a QL-compatible video mode. It is VERY important to START the emulator in this mode, starting it in another mode and switching to mode 4 or mode 8 later might not switch the screen and system variables to the required addresses for QL compatibility. If unsure how to do this, in the configuration screen which appears on startup of QPC2 (if it doesn't show, the emulator should be started by holding down SHIFT while you click on the QPC2 icon in Windows), under COLOUR DEPTH select QL Colours. Under Resolution, select 512x256. Optionally, under Emulation set the Memory value to a value not more than Super Gold Card 4MB memory if the software says it works on Super Gold Card (it won't normally make a difference but you never know).
What this does is force the emulator to a 512x256 screen at address (dec.) 131072 like a QL, and system variables to go at 163840 like a QL. You can check this in QPC2 by typing the command PRINT SCR_BASE and PRINT VER$(-2) for screen address and system variables respectively, This might not prove much - current versions of QPC2 report the system variables at 163840 and always seem to have a "QL" screen at 131072 which only becomes obvious after a QPC_QLSCREMU command (see blow, and you should read the manual to see how the various parameters possible for that command affect how it works),
I can't remember if CBZone runs in mode 4 or mode 8 - if need be enter a MODE 4 or MODE 8 command as relevant.
QPC2 has a command called QPC_QLSCREMU which can help when running older games. What it does is shadow copy the original QL screen memory address to the top left of the current screen. It deosn't do miracles but can sometimes help if you are trying ot run a game in any other colour depth or resolution.
If you suspect the program might not be compatible with QPC2, one easy way to check is to try running it on QemuLator, which even on an unregistered copy emulates a baseline BBQL quite well with 128K or up to either 256K or 384K (can't remember which) of RAM. QemuLator lets you use all QL ROM versions, so you can try the game on versions JM, JS or Minerva ROMs, for example.