Denial

Witzo wrote:How does this work?

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P=ST=0

This statement is not interpreted as double assignment in BASIC V2, rather the result of the Boolean expression ST=0 (either -1 if true, or 0 if false) is assigned to P.

Do I understand correctly that originally, the Z-code interpreter required 35k of RAM expansion (3k RAM expansion + 32k RAM in BLK 1,2,3,5) but now will work correctly with on a standard 32k RAM expansion? There are actually two different Z-code interpreters being talked about: TNT's implementation...

Shouldn't the DOS Wedge be "invisible" in RAM? The FE3 DOS Wedge is copied from the firmware ROM to the address range $0400 .. $0FFF, which is then write protected by FE3, and thus not available for other programs. trying to turn the DOS wedge OFF freezes the VIC, but only with full RAM c...

Would XPander 3 also be an option to get over the 32K hump? You can combine a +3K RAM expansion and a +32K RAM expansion with a slot expander. Note though, that the external +3K expansion is blocked from BASIC use (RAM in BLK1 takes precedence) and will not show up as extra 'BYTES FREE', the BASIC ...

[An animation in a smaller frame with <30 frames per second] almost seems doable in spite of the FE3's limits ... at least a simple demo could be pulled off? Let's see ... a 64x64 pixel bitmap needs 512 bytes, the FE3 RAM Disk achieves slightly more than 9 KB/s for load, which leads to ~18 frames p...

You can refresh a whole MINIGRAFIK bitmap sans attributes nearly 30 times per second. See here . It 'just' needs a more flexible RAM expander than FE3, like this one: - 256 'pages' with 8K each, i.e. 2 MB in total, - 4 registers in the I/O area, for BLK1..3 and BLK5, which allow to map any of the 25...

but how hard would it be to make an animated Dragon's Lair type game where the various frames of animation are bankswitched into the accessible memory of the VIC chip? The expansion port is not accessible by the VIC chip. Especially an external 3K expansion is not "seen" by VIC, even thou...

I'm using a VIC-20 with S-Video mod , and a Commodore 1084. They are connected with a LCA cable made from a DIN to 4x RCA break-out adapter and a normal A/V cable. The colour markings on the RCA ends of the DIN adapter happened to match the inputs of the 1084 (yellow: luma, red: chroma, white: audio...

Hi! It's nice to see some independent development regarding the MG picture file format. :D It sets the Gimp image type to indexed and sets the palette to a Vic-20 palette. http://people.myplace.net.au/~hawk@myplace.net.au/mike/retro_computing/vic-20/denial/Gimp%20plugin/GimpPluginColormap.png The ta...

PhilRanger wrote:Thanks. I understand what you mean. I was hoping some overlay using scan might have been possible to avoid forcing the user to go to hi-res altogether but maybe I'm just dreaming!

I was not talking about a full-screen bitmap. Just the characters around the player position must be taken care of.

I'm quite aware that opening the case and doing modifications on the mainboard is crossing the line for many people. Especially when it's in working order and there's no 'reserve' VIC-20 at hand. But then, how is applying the S-Video mod or internally wiring a uIEC (both of which have been done by o...

I want to skip redefining characters for mid positions for everything that is part of the decor, while having scrolling smoother than full character. Your routine just needs to take those characters of the background which are located 'beneath' the intended position of the player, and replace them ...

Actually, in the example I gave, such a DISPOSE NEXT command was not necessary, as the dangling FOR loop gets removed with a NEXT of the further enclosing FOR loop variable. Sometimes it pays off to know a little more about the inner workings of the BASIC interpreter. ;) Likewise, if there's a FOR l...

wimoos wrote:modifying the loopvariable from within the loop is ...

... much more harmless than leaving a dangling FOR loop on the stack.

I happened to use the following construct quite often lately - the lines: DO <statement> LOOP WHILE <condition> can easily be translated with a FOR loop in BASIC V2 thus: FOR P=-1 TO 0 <statement> P=<condition> NEXT P ... where <condition> is a Boolean expression which evaluates to either -1 (true) ...