I hope it's only because of a SPAM-filter.
Or is this theme outdated? If so, then pls remove the new topic!
Dear Zeddy Fans!
I am Zsolt Gaál from Hungary.
I got my first computer back in the fall of 1983. It was (of course) a ZX81. Therefore, when I found out that there are other enthusiasts out there keeping it alive, I was pleasantly surprised. So, for the 15th ZX-TEAM-Meeting (I wasn’t able to finish it for Zeddy’s birthday), please welcome my little present which you can find in the attachment.
The ZIP contains two files, SPONZY.ROM (which is a modified Spectrum ROM) and SPONZY_KBD.JPG, the latter shows how I ported the Speccy keywords to Zeddy keyboard.
(I’m not really keen on the layout of the Spectrum keyboard.)
For the sake of compatibility, I tried to keep every ROM entry point.
The „new” ROM has some additional features as well:
1. there’s the well-known improved version of the SQR function (Newton-Raphson method) in the code
2. you can switch (in runtime) to FAST mode with the
nnnn REM >=fast
command, where the „>=” is SHIFT+Y (!!) and „nnnn” is a line number. Whether you use the capitalized or the non capitalized version of the keyword is up to you. (e.g. „>=FAST” and „>=fAsT” are both good). Using this form of command, in case of running it with a Spectrum „REM” won’t effect its operation.
In case of an error or at the end of the program, (according to my expectations) it will automatically switch back to SLOW mode, which can be also activated through the program:
nnnn REM >=slow
3. you can invert the screen (printable area only, border not) with this formula:
nnnn REM >=invs
I already planned a SPONZY-hardware which expands Zeddy’s functionality (32K SRAM, 512K Flash, Kempston type Joystick interface), but it's not ready to use, so I was only able to test it on „EightyOne”.
With the help of the „Wav Loader” the Spectrum programs are readable and writable (LOAD/SAVE), and the programs saved this way are readable and runnable on emulated Speccy.
I don’t say it’s finished. I’m sure that there are some mistakes as well, but it’s at a stage where the more people see it, the better it is for further development. I will publish the source code with comments as well, as soon as possible.
Well, without further ado, enjoy!
p.s.: if you can run it on a real hardware, please write a few words to me about your impressions
EDIT: the attachment was removed. See the final version of SPONZY
Just tried it on eo.
Following hardware settings work:
ZX81, RAMPack 48K, soundcard disabled,chr$gen sinclair, Hires WRX, no drives, sponzy.rom writeprotect rom writes on everything else off
This is just a first test to get it running.
Please suggest any changes that encance capabilities.
It looks good and runs at reasonable speed.
Great work, can't wait to be back at home and write into an eeprom to test it on a real machine.
No problem, this is the better version - accordingly this theme is not a "gnawed bone" yet.
I tried it too with same settings.
Video? Hm, my laptop is poor to run "EO" and a Screengrabber both... maybe on my Son's machine. (or with mobile?)
Till then, here is a little demo - run at first on EO/ZEDDY/SPONZY and then on EO/SPECCY.
- (11.55 KiB) Downloaded 261 times
Shoulders of Giants (sg81)
Tree Forth (Tree4th)
ASZMICE07 (4k - doubled)
So I have room for 2 more ROM images.
What are the chances SPONZY will work in a real ZX81 with 32k RAM? Apart from being hooked up to some extra hardware like ZX1541, voice synth card, I/O card, joystick card, Everything else is pretty standard (i.e. no Hires WRX)
SPONZY uses WRX for display, so you need a WRX-compatible (e.g. SRAM) memory in 16K-32K region.
Readed topic "ROM's again" I think your ROM-bank can switch by 8K only.
Your decoding will need to take an extra address line into consideration, and the address line will need to be connected to the chip.nama wrote:Does anyone know if i Just fill up the last two 8k ROM slots on my 27c256 with this 16k rom image will the zeddy be able to access all of the 16k?
IIRC you use a13,14 & 15 on a switch to select the bank. Unless you change your wiring to put a13 on the chip to select 4 banks of 16k this won't work for you.
The requested video is ready: http://www.youtube.com/watch?v=4DLTOLEBrkIRWAP wrote:Now that does sound interesting - how about uploading a video of it running in EightyOne
The EO was a little bit slower (~35fps) because of screenrecording.
Did somebody try it already on a real hw?