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#91
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
#92
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
#93
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.
#94
What's the reason to avoid EPROMs? They are easy to source and cheap. I always use EPROMs to replace the internal ROMs.
#95
Pretty girls added as a decorative element is basically turning them into objects.
As a visibly masculine heterosexual guy, I can understand that. But that's because I have an ancient mystical quality called empathy... Think about it as a superpower. I know it's hard to understand at first... Give it some time.
As a visibly masculine heterosexual guy, I can understand that. But that's because I have an ancient mystical quality called empathy... Think about it as a superpower. I know it's hard to understand at first... Give it some time.
#96
Not a very elegant solution but you can still source W27C512 ICs. Indeed I recently purchased 5 from eBay for another project.
But you need to handle pin 1 (A15) as this is not connected on the motherboard.
I must stress I have only done a simple boot test while pulling pin 1 to GND but my 464 boots ok.
You cannot view this attachment.
But you need to handle pin 1 (A15) as this is not connected on the motherboard.
I must stress I have only done a simple boot test while pulling pin 1 to GND but my 464 boots ok.
You cannot view this attachment.
#97
Quote from: lmimmfn on 14:57, 06 July 25Quote from: VincentGR on 14:51, 06 July 25They/Them obviouslyQuote from: Gryzor on 14:45, 06 July 25Ohhh, I see. And the car, what about the car?Quote from: VincentGR on 14:42, 06 July 25What's wrong with a pretty girl and a great car on a picture...Who told you she/he/it/@ is a girl, how dare you presume
A la chica y al fondo le faltan bastante retoque
The girl and background need a lot of finishing
#98
I was doing some more coding the other day with Primal (my kernel) and had an interesting problem - that was, with my current memory routines how to deal with 4mb+ RAM to access all 256 16kb blocks plus internal memory with a single byte. I came up with a solution, I now have 3 heaps - An application heap, a system heap and a buffers heap. keeping the API currently almost as it was, I added a Heap selector which lets me change heaps then use the other APIs like bankselect etc... for 4mb+ systems, I gave 3mb+ to applications, and 512kb to system and buffers each. For 2mb+ systems, half that, until down to 128kb systems (that's 64kb extra ram - so 128kb total), they only have the 3 heaps are merged. This sharing of heaps as a fallback works extremely well on paper at least - meaning if there is an abundance of RAM, the system can guarantee it's own RAM and RAM for buffers, but if there is not much RAM, they fall back to a single heap where it's more a typical CPC program (shared space for program, jumpblock, buffers). The loader now defaults to working with unexpanded 464 or 664 and gives about 35kb available shared after the kernel is loaded no longer requiring an expanded memory driver. I'm not yet overwriting the firmware jumpblock - but in time I will to use all RAM up to #C000. But I also created a virtual memory variant for unexpanded machines which gives 1 x 64kb+ heap and 2 x 64kbMemory heaps - which will work fine on M4 or other Mass Storage - obviously not useable for Tapes or Floppy Discs. This Virtual Memory isn't best for expanded machines but of course will work... a more intelligent virtual memory version would be best, that is to use a LIFO model for swapping files into physical expansion RAM - maybe in future I will code this.
Actually I could create a 4th pseudo-heap which is like a reserved, do not use heap - so that if someone was e.g. using an AMSDOS RAM expansion, we can not corrupt it, but
Next. to recode my Malloc (SysHeapAlloc) and Free (SysHeapFree) to use a better system than the slow iterate through banks, then iterate through lists - it takes quite a bit of time (fractions of a second though) to find a free block after e.g. 500 filled blocks.
I'm going to reinvestigate my RAT (RAM Allocation Table idea) - I think that is likely best, it's definitely the fastest, but it does have byte-aligned blocks which are the minimum memory allocation size even if you want smaller.
It isn't runnable yet, some code can be stepped through.
Latest Coding Status here:
https://docs.google.com/spreadsheets/d/14JQa3cTEd9fIz9lyoQRkzVc5xBz5FhEdr_DC41xPkJs/edit?usp=sharing
Actually I could create a 4th pseudo-heap which is like a reserved, do not use heap - so that if someone was e.g. using an AMSDOS RAM expansion, we can not corrupt it, but
Next. to recode my Malloc (SysHeapAlloc) and Free (SysHeapFree) to use a better system than the slow iterate through banks, then iterate through lists - it takes quite a bit of time (fractions of a second though) to find a free block after e.g. 500 filled blocks.
I'm going to reinvestigate my RAT (RAM Allocation Table idea) - I think that is likely best, it's definitely the fastest, but it does have byte-aligned blocks which are the minimum memory allocation size even if you want smaller.
It isn't runnable yet, some code can be stepped through.
Latest Coding Status here:
https://docs.google.com/spreadsheets/d/14JQa3cTEd9fIz9lyoQRkzVc5xBz5FhEdr_DC41xPkJs/edit?usp=sharing
#99
Why is it so dark? It's almost impossible to see what on earth is actually going on.
#100
Quote from: VincentGR on 14:51, 06 July 25They/Them obviouslyQuote from: Gryzor on 14:45, 06 July 25Ohhh, I see. And the car, what about the car?Quote from: VincentGR on 14:42, 06 July 25What's wrong with a pretty girl and a great car on a picture...Who told you she/he/it/@ is a girl, how dare you presume