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levi - you know, if I just wrote the carts in asm, it'd be 'easier' that way; this interplay of the C compiler to the asm is the problem here; just soooo much crap to look at to trace through where the hell its going :) using the LD A, LD MB, A, JP.SIS works too, gets into the right area. But...

alright, had a quick fiddle .. RL can wait just a moment, right? yeah, so putting in a JP.LIL %1C0000 (or whatever address) is sufficient. Yeah, the JP ... (foo)... is for when using a memory location and stuffing the address in there, for when the monitor/flashtool want to jump around without...

yeah 6502 zero page was an awesome hardware hack; always loved that, and moving things to page zero so you could save some cycles. Good times :) I'm more used to 6502 than z80, but went with z80 on the ZZ so it'd be some learning, and because of course the z80 is still widely available. I...

yeah I've had a similar suspicion or a couple days since I started banging on this again; just no time to get near the damned thing in awhile :/ See, I can actually jump around in the same region of memory no problem; jumping from 0x0Cxxxx to 0x1Cxxxx is blowing up but I've not had a time to...

I've not had much time, but I can say .. the code is doing: .assume ADL=1 JP (IY) ... looks okay to me, offhand. The .assume ADL=1 tells the assembler to use the 24bit addressing and such. I should trt with jp.lil to be specific though, but another night. RL is too busy of late :/ jeff

yeah, for sure, it looks like the C compiler is doing some funny business. I'll have to try some inline asm to do the jump to cart. I actually think theres some toolchain gotchas/bugs here .. I'm currently using official Zilog ZDS-II toolchain (in virtualbox natch), as I wanted 'some stability'...

ez80 can run in pure z80 mode, or an enhanced mode with larger addressing. Its pretty funky :)

Trying to sort out some of the assembly trickery; I'm not super hot at asm (especially z80 asm :) but.. My base 'firmware' (what happens first, and especially if no cart present; could keep a BIOS in there for carts to use, or let carts be 100% self contained after the firmware verifies there...

current limiting hopefully avoids that but yeah when the thermistor got pulled out .. that's enlightening (or thankfully -not-!) ... next design, backup heat sensing? Ordered new parts from a kit though so won't be a homemade printer next build but more stable :) I have messed up print job...

Oh consistency has been shot forever Zikzak project Zik80 (z80 variant) Zikzak <Zik80> SBC (single board computer) version (there are many other variations) Zikzak SBC rev 1 thru 4 Zikshield for ZZr3 (top pcb) Zikpower Then of course accessories... I'm surely forgetting some Zikcase top and...

Nothing too interesting to show today, but its still exciting to me ;) When coding on the z80 side, I've tended to cheat and just flash to the device ROM; keeps a lot of things simple, but at the same time .. you risk wearing out the flash prematurely. I fiddled for awhile and got things all...

Blast, looks like my 3d printer wrecked itself good (by which I mean, I wrecked it :) .. it was mostly homemade, and I never got around to making a fancy wire guide, so there was a wire harness just hanging down over the print area,m sweeping around behind the print nozzle. I was trying to...

One thing thats interesting too is .. 'glitching' the screen is really where you have some wiggly columns, since you've been doing GPIOs and causing some slight microsecond delay, so ap pixel gets to be a tiny bit too big, etc. That only shows if you're doing non-black; one option of course is...

The EEPROMs I use are read/write just like a RAM; you're more thinking EPROMs, that need a UV eraser/etc. Theres high voltage erase and so on (that use a 12V erase cycle etc), but mine just write and good to go. Look up AT28C256 (for a 32KB chip); theres a lot of similar newer parts out there...

Its 'general purpose', so coudl do a lot of things; I've not finished any real BASIC interp yet, but its on my bucket list. Course, any number of small (and classic from 30 years ago) BASICs could compile, and some classics (from CP/M, or the original MS BASIC) can be ported to run on there...

Case design is coming along pretty rapidly; I mean, I'm no designer, and using 3d printing puts a lot of limits on you. ie: You have a hard time doing rasied areas or concaves etc .. and the plastic I'm using is fairly strong but brittle (doesn't bend), so if you have jacks all over.. you can't...

... and, there are billions of options. So, you pick one that matches your goals, and try it out, and go from there. I wanted to avoid anything with 'high power needed to flash' or separate flashers, and I really like the 'flash that acts like RAM' .. it keeps things easy. But, I also designed a...

yes, quite so. Early on I wanted carts to more or less act like RAM .. so they can be ROM, or eeproms, or any number of things that the bootloader could set up .. but for now the carts I've been using are the old atmel flash that are read/write exactly like RAM (just slower for writes). This way...

To be clear.. 'working so far' is in reference to the Zikshield; the ZZr3 has always been working very well, for quite some time (a year?) .. so I'm specifically talking about adding new circuitry (amp, ftdi etc) on board to the shield, plus the jacks and extras. So working so far .. the shield...

Only had a few minutes, but I put the power/serial USB jack on; needs a pile of solder, takes a fair amount of force when putting in/out the cable! .. and FTDI and VGA jack, and the damned thing comes up when the boards are put together. I gotta say .. dorky as it is, it looks pretty sweet :)...