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#1
Technical support - Hardware related / Re: Disc Missing and Bad Comma...
Last post by eto - Today at 21:11And... according to Murphys Law it was of course the last possible IC: The WDC9216 data separator!
Of course the only IC I could not test with my IC tester. Of course the one that was not mentioned in any other thread ever.
Of course the only IC I could not test with my IC tester. Of course the one that was not mentioned in any other thread ever.
#2
Quote from: ZorrO on Today at 19:57I'm looking at your video to see what effect you want to achieve. And on Amstrad you don't need machine code for this.Oh, I get this. This is an exercise purely to learn asm on a few different platforms. In fact the absolute easiest way would be to have a script to display two full screen images - but that's not why I'm writing this.
I started programming when I was about 14/15 when I got DevPac 3 for the Amiga for my birthday, and I just couldn't understand it. I tried a number of times throughout the years to go back and learn it and it's been a bit of a mental block for me. About 18 months ago I started getting into retro systems and decided to finally learn how to code in asm. I've been exploring different modern 8-bit systems like the Commander X16, Neo6502 and Agon Light, and I thought I'd go back to the very first system I ever had - the Amstrad CPC 6128 and see if I could write it for that.
The demo/app isn't for anything, it doesn't really do anything - it's a few loops, keyboard input, shapes, screen mode changes, displaying an image tile or a sprite etc. but it's enough for me to learn a few common skills across a number of platforms. I'll expand on it to try new things as I learn more. One thing I've already thought of is having a data structure for all my rects that loop through to display them. Right now I could do that in C/C++ or Java, but I've got no idea about this in asm so it will be fun learning.
#3
S
Technical support - Hardware related / Re: old model 464 with garbled...
Last post by salvogendut - Today at 20:30Quote from: McArti0 on Today at 19:52After Swith On CPC. ROMDIS line to VccHey thanks for replying! I am not really familiar with the platform so if you could elaborate a bit what ROMDIS is and what should I do with it, that'd be super helpful!!
O screen You should see narrow stripes.
#4
I'm looking at your video to see what effect you want to achieve. And on Amstrad you don't need machine code for this. You can do it in a few lines of Basic or even display such a screen as a text file with a few control codes. For the address text you can use characters with codes from 128 to 143, and for option font use narrow font with a 4x8 pixels matrix in MODE 0, or switch bottom of screen to MODE 1. Last one thing can't be done in text file. The only difficulty is to get a lighter gray color that is not in palette, there are 3 ways to do this but each has a certain drawback.
#5
Technical support - Hardware related / Re: old model 464 with garbled...
Last post by McArti0 - Today at 19:52After Swith On CPC. ROMDIS line to Vcc
O screen You should see narrow stripes.
O screen You should see narrow stripes.
#6
S
Technical support - Hardware related / Re: old model 464 with garbled...
Last post by salvogendut - Today at 19:42question for the wise ones: how can I debug ram chips without an oscilloscope? If I used an external rom box that is able to boot to a diagnostic program , would that tell me exactly which chips are failed? I have an ULIfAC , can I use that to boot a diagnostic rom? Would that work? I have seen Noel's Retro Lab videos where he is using a Dandanator with a diagnostic program that somehow shows red or green lines on screen corresponding to ram chips
#7
Quote from: andymccall on Today at 18:05... The next bit I need to do is take a png, export it into a format the CPC can understand, then load the .bin in my project and display it over the black stripe. ... If anyone has any tutorials or tips for doing this then I'd appreciate the links. I have managed to display a full screen image, but that was a bit easier as I could conver the whole image into a format for the whole graphics memory, displaying a smaller image over the top of another one seem to be much harder.
Here I would like to do some advertising for the existing Wiki page about this topic as well as for my small plugin for the GIMP graphics software (link at the end of the Wiki page, discussion on this forum page). The plugin provides a small BASIC program that in turn installs a small assembler program to copy the graphics data to the screen - currently always at the upper left corner, but this can be changed.
#8
Quote from: eto on 21:19, 21 June 25Honestly, I'm hesitant to connect the DDI1 clone. Would it be a good idea to try it?Quote from: Shaun M. Neary on 23:50, 20 June 25Either inside the Zaxon DDI deviceThis particular device is really just a DDI1 clone and does not contain any RAM.Quote from: angelcaio on 22:48, 20 June 25Could it have been caused by the DDI1 clone?
I'm not an expert (let's wait for Bryce to confirm) but I would be surprised if the DDI could cause that. The internal RAMs are not directly connected to any lanes on the expansion bus.
But you should check the voltage that the CPC receives from the monitor if that's close to 5V or if it's maybe too high.
Everything worked fine for two or three days after the DDI repair and before the RAM (IC120) D0 failed.
Is there anything i can do beforehand ton be sure?
Is IC0 connected to pin 26 in edge connector?
Thank
#9
Thanks for all the help.
Here's a video of what I've learned and managed to do so far:
I tried to do the mixed mode, but it was beyond me at the moment :-/ The next bit I need to do is take a png, export it into a format the CPC can understand, then load the .bin in my project and display it over the black stripe. I think because of the complexity of the Amstrad CPC's graphics system, this is going to be much harder than on the other systems I've written this demo for. If anyone has any tutorials or tips for doing this then I'd appreciate the links. I have managed to display a full screen image, but that was a bit easier as I could conver the whole image into a format for the whole graphics memory, displaying a smaller image over the top of another one seem to be much harder.
Source code is here - https://github.com/andymccall/bitriotdev-cpc for those experienced dev's that fancy a laugh at a newbie
Here's a video of what I've learned and managed to do so far:
I tried to do the mixed mode, but it was beyond me at the moment :-/ The next bit I need to do is take a png, export it into a format the CPC can understand, then load the .bin in my project and display it over the black stripe. I think because of the complexity of the Amstrad CPC's graphics system, this is going to be much harder than on the other systems I've written this demo for. If anyone has any tutorials or tips for doing this then I'd appreciate the links. I have managed to display a full screen image, but that was a bit easier as I could conver the whole image into a format for the whole graphics memory, displaying a smaller image over the top of another one seem to be much harder.
Source code is here - https://github.com/andymccall/bitriotdev-cpc for those experienced dev's that fancy a laugh at a newbie
#10
Thanks you for your feedback.
@Jean-Marie : well noted. I will look at this protection for a future version. It's never easy with the dsk format which isn't really designed to handle protected tracks.
@andycadley : I'm very curious about your test code. Don't hesitate to let me know if you notice any differences. This will help me improve the emulation.
@Jean-Marie : well noted. I will look at this protection for a future version. It's never easy with the dsk format which isn't really designed to handle protected tracks.
@andycadley : I'm very curious about your test code. Don't hesitate to let me know if you notice any differences. This will help me improve the emulation.