#Z88dk cplot black red code

bin2h.cpp - raw binary to c header file converter.B is for BRIGHT, changes both PAPER and INK.F is for FLASH, swaps the PAPER and INK every 16 frames.Color dataĬolor data is stored linearly, where each byte overlays a 8x8 block of bitmap data.

#Z88dk cplot black red code

I have no idea whatsoever why they would split the rest of the bits the way they did, but there you go.Įasiest way to deal with this is with a scanline start lookup table, but you could do the swizzling with code too. That only works up to 8 scanlines though. The Y coordinate is split so that printing single glyphs would be faster - just increment H by one and you're on the next scanline. The addresses map to (see above links for prettier graph): HĮach scanline is stored linearily. There's 32*8=256 x 192 pixels on the screen. Memory below 0x8000 is 'slow' because the video hardware has priority to it fast(er) routines and data should be in the upper portion. It should be possible to use from 5b00 to ffff though (~41k). So we have about 40k of usable RAM normally.

contended memory and contended io-port 254 make the above values largely useless.

different machines may vary by one clock.

one scanline: 128 clocks pixels, 24 clocks right border, 48 clocks retrace, 24 clocks left border.

after frame interrupt, 64 scanlines before first pixel.

i/o port 254 controls border color (bottom bits 0,1,2) and speaker (bit 4).

rom character set is at 0x3d00 - 0x3ff and contain 8 bytes per glyph, starting from ascii 32 (space).

In speccy emulator, be sure to set hardware->fast tape loader on unless you want to die prematurely of old age.

a zx spectrum emulator, I like speccy.

Note that I'm doing this on windows, but what I've got together here may be helpful for figuring these things out on other platforms too. It's (still) (well, probably forever) a work in progress, but someone may find it useful.

Here's a bunch of stuff I've cobbled together to make a zx spectrum toolchain.