-
Games that crash because of contended memory.I find these are really annoying. You load up a game like Astro Marine Corps, Fantasy World Dizzy, Dizzy: Prince Of The Yolkfolk and so on (the init…
... a crash when the I register points into contended ram. Emulators ... 3. I can see the snow effect but without other problems ... -
Face-Off: ZX Spectrum vs. Commodore 64I found an old oldish, but very informed and interesting article on the ole Spectrum vs. Commodore 64 argument. The article explains the technical d…
... they were actually pixel-scrolling the scoreboard characters in software ... b] does both hardware scrolling for the foreground and ... bit of planning (any register write happens pretty much when ... with things; for horizontal scrolling there are numerous examples ... -
Face-Off: ZX Spectrum vs. Commodore 64I found an old oldish, but very informed and interesting article on the ole Spectrum vs. Commodore 64 argument. The article explains the technical d…
... vertical movement, the hardware scrolling certainly can't deliver two ... independently scrolling windows on the same ... at least the horizontal scroll register (the vertical can't ... ). And two independent windows scrolling at half a character per ... -
Better arrangement for video memory?While doing some documentation work for the ZX-Uno project, I compared the advantages of the weird layout of the ZX Spectrum against a linear layout.…
... are for horizontal scrolling, not vertical. For vertical scrolling you just copy ... overflow bits in the A register, then move on to the ... -
Buffer to screen - how much?[FONT=Calibri][SIZE=3]I am starting to build a new game and am researching different ways to accomplish what I need to do. My question is, is it poss…
... - eight rows of pixel scrolling. Just instead of using a ... for one pixel scrolling. For two pixel scrolling, you really need ... />
The really fast horizontal scrolling comes from pre-loading 16 ... scenery blocks into 16-bit register pairs and then using ... -
2014 Games ListNote: Due to forum update policies, the latest version of the list will always be found somewhere near the end of this thread. [old] Any problems …
... can be won on The Register (probably UK residents only) [[URL ... Demo[/B] (a nice parallax scrolling demo) [[URL="http://www.worldofspectrum ... -
Snowfall effectHow do you go about creating a snowfall effect like the one in Yeti? Now don't laugh, I'm currently printing 32 UDG's of dots OVER the top of my gam…
... it I would use the scrolling routine as is, but just ... snowball down. That way the snow will appear to be falling ... -
64x48 monochrome big pixels display ideaHi. I was playing with this idea of having a simple 64x48 bytes buffer, 1 byte per pixel, then a renderer which would take that buffer and render it…
... , another for OR. The extra register operations would probably exceed the ... do a copy. For horizontal scrolling, put the start address of ... would work just fine for scrolling any number of steps vertically ... -
RFC: 64 column font codeIn BASIC, type CLEAR 49999 then import the code at 50000. Then type RANDOMIZE USR 50000. This will create a new channel and attach stream #4 to it. A…
... specific screen location, line wrapping, scrolling,
;* clear screen, the character ... position.
;**************************************************
print_64:
; register a contains character
; clc ... -
Composite picture qualityI have read many many discussions here about the composite video modification of the Spectrum 16/48K models. I have choosen one of the simplest comp…
That's a fix for the ULA snow effect when the Z80's I register is set to point at contended memory. Won't do anything for the picture quality.
B -
Can anyone show a slight diagram of how pokes work in a jet set willy game for example?I know its kind of something to do with machine code and Memory addresses etc but would be nice to see a youtube video or some drawings etc ? .Many t…
... scanning the keyboard, drawing sprites, scrolling etc, then store then on ... programs while watching memory and register changes. -
Function with push and popIm trying to see if I understand push and pop when it comes to using to pass parameters to functions: [code] LD HL,16384 LD A,5 Push AF Ld A…
... to load it into a register from memory and then perform ... directly without using an extra register. Having said that, and looking ... -
Nirvana+ - Which games would you reproduce?Which games would you reproduce using Nirvana+ Early single screen or non-scrolling arcade games that could utilise the Nirvana+ engine for enhanc…
... /> Early single screen or non-scrolling arcade games that could utilise ... /> Rod-Land 1990 Jaleco
Snow Bros. - Nick & Tom 1990 ... -
How would you approach parallax?So ... there is this trick by Joffa that we all know...of waiting for the ULA to reach certain pattern on the screen using the IN command. And then s…
... by HL via A register. And it does it ... />
If I start scrolling the screen when screen ray ... to have an intermediate register A. You need to ... besides RLD for 2 pixel scrolling?
This ... up with for 2 pixel scrolling.
[code]
... -
Skate Crazy on grey +2I've downloaded "Skate Crazy" from WoS, recorded it on a real tape and tried to load to my grey Spectrum+2. Game (both parts) works only in 48k mode.…
... a crash when the I register points into contended ram. Emulators ... an emulator that supports ULA snow (such as SpecEmu)
128K memory bank selection to avoid contention issuesI'm currently developing a game and I'm trying to get my head around the memory contention issues of the various 128K/+2/+2A/+3 spectrum models in or…
... shouldn't set the I register to a value in the ... it the same as the snow effect which is caused when ...im looking for a horizontal scroll routinehi, im looking for a horizontal scroll routine. i read somewhere that you can do it with at 'to' statement, somewhere in a print routine. althoug…
... $".
All of the scrolling is done in these two ... . The graphics info for each "snow-capped mountain peak" uses 18 ... of 140 secs is for scrolling 128 "mountains" (ie. 4 screens ...Interrupts, 16k Spectrums and snowI'm writing something for the 16k Spectrum and I want to use interrupts. The avilable documentation doesn't seem clear enough for me to figure out ho…
... register to 37, you can use the ROM and avoid any snow ...Gandalf [z88dk][Nirvana Plus][128Kb]Gandalf 1.00 [url="https://drive.google.com/open?id=1T9HK0_isoMrfogSIJVhPGehjVIdFus4c"]Download Ver 1.00[/url] Long after the destruction of t…
... . If the "I" register points into contended memory, snow will appear on ... the display. If the "I" register points ... the top 16k without seeing snow and you can't execute ...Gandalf [z88dk][Nirvana Plus][128Kb]Gandalf 1.00 [url="https://drive.google.com/open?id=1T9HK0_isoMrfogSIJVhPGehjVIdFus4c"]Download Ver 1.00[/url] Long after the destruction of t…
... . If the "I" register points into contended memory, snow will appear on ... the display. If the "I" register points ... will neither crash nor produce snow on the display.Gandalf [z88dk][Nirvana Plus][128Kb]Gandalf 1.00 [url="https://drive.google.com/open?id=1T9HK0_isoMrfogSIJVhPGehjVIdFus4c"]Download Ver 1.00[/url] Long after the destruction of t…
... . If the "I" register points into contended memory, snow will appear on ... the display. If the "I" register points ... will neither crash nor produce snow on the display.
[/ ... $40–$7f. I get the snow, sure, but the machine doesn ...Gandalf [z88dk][Nirvana Plus][128Kb]Gandalf 1.00 [url="https://drive.google.com/open?id=1T9HK0_isoMrfogSIJVhPGehjVIdFus4c"]Download Ver 1.00[/url] Long after the destruction of t…
... . If the "I" register points into contended memory, snow will appear on ... the display. If the "I" register points ... will neither crash nor produce snow on the display.
[/ ... $40–$7f. I get the snow, sure, but the machine doesn ...Gandalf [z88dk][Nirvana Plus][128Kb]Gandalf 1.00 [url="https://drive.google.com/open?id=1T9HK0_isoMrfogSIJVhPGehjVIdFus4c"]Download Ver 1.00[/url] Long after the destruction of t…
... . If the "I" register points into contended memory, snow will appear on ... the display. If the "I" register points ... will neither crash nor produce snow on the display.
[/ ... $40–$7f. I get the snow, sure, but the machine doesn ...The I register pointing to $40–$7f causes ULA snow and a crash. Or does it?I have heard it from numerous sources, including a few members of this forum, that 128K/+2 machines crash if the I register points to a range of $40–…
... these machines, the ULA snow effect works a little different ... the snow effect kicks in if the I register is in ... contended bank, then the snow effect will appear [i ... post will cause the snow effect, even though I ... is contended, so the snow effect kicks in. (The ...The I register pointing to $40–$7f causes ULA snow and a crash. Or does it?I have heard it from numerous sources, including a few members of this forum, that 128K/+2 machines crash if the I register points to a range of $40–…
... actually state which cases cause snow and which actually crash the ... register when a contended RAM bank is paged in causes the snow ... now—is, If you see snow, you might get a crash ...The I register pointing to $40–$7f causes ULA snow and a crash. Or does it?I have heard it from numerous sources, including a few members of this forum, that 128K/+2 machines crash if the I register points to a range of $40–…
... we were also talking about snow. He did leave out an ... snippet that changes the I register within my ISR (with the ...The I register pointing to $40–$7f causes ULA snow and a crash. Or does it?I have heard it from numerous sources, including a few members of this forum, that 128K/+2 machines crash if the I register points to a range of $40–…
... ]The I register pointing to $40–$7f causes ULA snow and a ... correct data... so shows as "snow" (corrupt or incorrect picture information ... . The contents of the refresh register (R) are placed on address ... the contents of the interrupt register (I) is put on ...The I register pointing to $40–$7f causes ULA snow and a crash. Or does it?I have heard it from numerous sources, including a few members of this forum, that 128K/+2 machines crash if the I register points to a range of $40–…
... itself simply reads the R register, places its value into A ... mucks about with the I register but restores it prior to ... .e. contended/non-contended. The snow-effect pattern changed in Test ... snow effect is triggered not just by setting the interrupt register to ...
