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#1
Quote from: GUNHED on Yesterday at 16:25Well, just add a ZIP here...
Did you not read XeNoMoRPH's earlier post first?
#2
Technical support - Hardware related / Re: cable DDI-1 for CPC 6128
Last post by Rabs - Today at 17:44Thanks for the info. For some reason I struggle when making ribbon cables and can never trust myself to get them the right way up. 
And really I should go to the effort of adding an edge slot key but never do.
Anyway just in case I forget which way up it should go, I always leave my future self a handy hint.
You cannot view this attachment.
And really I should go to the effort of adding an edge slot key but never do.
Anyway just in case I forget which way up it should go, I always leave my future self a handy hint.
You cannot view this attachment.
#3
@eto I managed to load Relentless, and I think I can see that issue. It is just shaking and I agree it makes it unplayable. I think I know where the issue is, and I will try to fix it. As I understand, what they do is a combination of actually shifting pixels on screen and changing the duration of hsync (the one the is part of c-sync on GA's output, not the one on GA's input). My problem is that I shift twice too much when duration of hsync changes. As a result, instead of shifting one pixel per frame, it shifts by 1 pixel, 2 pixels, 1 pixel, 0 pixels. I probably messed up something with timing when waiting for csync to end.
#4
Technical support - Hardware related / Re: cable DDI-1 for CPC 6128
Last post by SerErris - Today at 16:20If you get the cables upside down, all signal lines from the drive will get connected to GND and all signal lines from Interface will get connected to GND as well.
However it looks like that the architects of the CPC again thought about that issue and developed protection
Lets analyse the technology if you connect one end wrong way.
Lets see how that would look on CPC end:
All output signals from 765 Controller are connected to 74LS38 "2-INPUT POSITIVE-NAND BUFFERS WITH OPEN-COLLECTOR OUTPUTS". Those open collectors mean, that they can only pull a line down, but cannot send out +5V on their own. It requires that the line is getting pulled up via a pullup resistor against +5V power source. Those pull-up resistors are located in the drive itself. That does two things: First the current possible to flow from +5V to this input is limited by this pullup resistor. Second this open-collector output will get connected to GND if you put the cable upside down, so it is anyhow and allways GND and no current will flow at all, so no damage to that side.
Input signals to 765 are connected the other way around via a Schmidt-trigger buffer chip, that also requires a pull-up resistor. Those input-pull ups are located in the interface of the CPC and the only current flowing is from +5V from CPC to GND in the drive via the pull-up resistor. That means the input is protected, it will never get any high current flowing in. The maximum current in this particular case at +5V with 680Ohm pull-up is 7.5mA .. That is the total impact per line to the power supply of the CPC. So for any input signal there is no harm to the CPC.
Now lets look at the drive end:
Here again all Output lines are requiring pull-ups and connecting the outputs directly to GND will not harm them in any way. There is simply no current going through it at any time.
Regarding the input lines. They are all connected again to pullups (as described above). In the drive case it is 1k resistors so the current is even lower at 5mA. This is very low and it will get directly go to gnd, and that is the maximum current that is drawn per line from the power supply. As this is a 1A power supply it also will have no problems with it.
The last lines that are potentially dangerous are our beloved +5V power supply lines for DDI-1.
On the CPC side of things, there is no damage, as the lines are directly connected to GND and that does not harm the CPC at all.
However it is potentially dangerous on the drive side as this can grill the voltage regulator. It will have no effect on the drive logic (the drive itself), but it may damage the power supply of the drive. Also there are two independent +5V rails inside the power supply. One is for the drive logic itself and one is just for the power supply for the DDI-1. However those 7805s typically come with short protection or overheat protection. If you would short the output to GND it will proabably overheat at some point and then just shut down (no power injected any longer). The worst case would be, you need to replace a burned 7805, which you can then replace with a proper one with short protection nowadays. Maybe that is a good idea anyhow :-)
TLDR:
All in all - nothing will probably happen if you connect the connector upside down and looking at the CPC side of things, actually nothing will happen if you connect it upside down. It could potentially grill the 7805 in the drive, that should power the DDI-1 but that its about it and probably (not sure as my Japanese for the original Sanyo part is not that good :-) ), even that is protected against in the regulator itself.
There is one last thing to mention.
With the correct cable it is impossible to connect it the wrong way. The cable had a particular nose on the drive side and a gap in the connector on CPC side, that prevents it from being connected wrong. So all this topic is a pretty modern issue, where people do not have the original plugs with the coding in the connector to ensure correct connection.
If you look at the connector for the drive on the CPC there is the gap in the pcb, where there is a key in the connector. So you actually would not be able to insert it the wrong way.
Of cause for the Schneider CPC 6128 variants it would even be the connector itself, that will prevent it from getting plugged in the wrong way (Centronics V-Shaped connector)
However it looks like that the architects of the CPC again thought about that issue and developed protection
Lets analyse the technology if you connect one end wrong way.
Lets see how that would look on CPC end:
All output signals from 765 Controller are connected to 74LS38 "2-INPUT POSITIVE-NAND BUFFERS WITH OPEN-COLLECTOR OUTPUTS". Those open collectors mean, that they can only pull a line down, but cannot send out +5V on their own. It requires that the line is getting pulled up via a pullup resistor against +5V power source. Those pull-up resistors are located in the drive itself. That does two things: First the current possible to flow from +5V to this input is limited by this pullup resistor. Second this open-collector output will get connected to GND if you put the cable upside down, so it is anyhow and allways GND and no current will flow at all, so no damage to that side.
Input signals to 765 are connected the other way around via a Schmidt-trigger buffer chip, that also requires a pull-up resistor. Those input-pull ups are located in the interface of the CPC and the only current flowing is from +5V from CPC to GND in the drive via the pull-up resistor. That means the input is protected, it will never get any high current flowing in. The maximum current in this particular case at +5V with 680Ohm pull-up is 7.5mA .. That is the total impact per line to the power supply of the CPC. So for any input signal there is no harm to the CPC.
Now lets look at the drive end:
Here again all Output lines are requiring pull-ups and connecting the outputs directly to GND will not harm them in any way. There is simply no current going through it at any time.
Regarding the input lines. They are all connected again to pullups (as described above). In the drive case it is 1k resistors so the current is even lower at 5mA. This is very low and it will get directly go to gnd, and that is the maximum current that is drawn per line from the power supply. As this is a 1A power supply it also will have no problems with it.
The last lines that are potentially dangerous are our beloved +5V power supply lines for DDI-1.
On the CPC side of things, there is no damage, as the lines are directly connected to GND and that does not harm the CPC at all.
However it is potentially dangerous on the drive side as this can grill the voltage regulator. It will have no effect on the drive logic (the drive itself), but it may damage the power supply of the drive. Also there are two independent +5V rails inside the power supply. One is for the drive logic itself and one is just for the power supply for the DDI-1. However those 7805s typically come with short protection or overheat protection. If you would short the output to GND it will proabably overheat at some point and then just shut down (no power injected any longer). The worst case would be, you need to replace a burned 7805, which you can then replace with a proper one with short protection nowadays. Maybe that is a good idea anyhow :-)
TLDR:
All in all - nothing will probably happen if you connect the connector upside down and looking at the CPC side of things, actually nothing will happen if you connect it upside down. It could potentially grill the 7805 in the drive, that should power the DDI-1 but that its about it and probably (not sure as my Japanese for the original Sanyo part is not that good :-) ), even that is protected against in the regulator itself.
There is one last thing to mention.
With the correct cable it is impossible to connect it the wrong way. The cable had a particular nose on the drive side and a gap in the connector on CPC side, that prevents it from being connected wrong. So all this topic is a pretty modern issue, where people do not have the original plugs with the coding in the connector to ensure correct connection.
If you look at the connector for the drive on the CPC there is the gap in the pcb, where there is a key in the connector. So you actually would not be able to insert it the wrong way.
Of cause for the Schneider CPC 6128 variants it would even be the connector itself, that will prevent it from getting plugged in the wrong way (Centronics V-Shaped connector)
#5
And Italian, French and German versions will follow very soon, according to Jordi (on the following message).
He says it's very easy to edit thanks to the PAKET engine... That engine needs to go public ASAP (or at least they should do like Carmack and release it when they create the PAKET 2.0 one).
He says it's very easy to edit thanks to the PAKET engine... That engine needs to go public ASAP (or at least they should do like Carmack and release it when they create the PAKET 2.0 one).
#7
English versión out !!!
https://twitter.com/jsureda/status/1786118066004271440?t=ennhjhIYAsbGN4lrlz31xQ
https://twitter.com/jsureda/status/1786118066004271440?t=ennhjhIYAsbGN4lrlz31xQ
#8
#9
Quote from: iXien on Today at 07:54@SyX , a little bit of topic, but the more I play this FLIPULL+ version, the more I'm asking myself if it would be possible to convert the game on CPC? With these new GFX, you give a CPC touch to the game, more than a "Plus" touch. But I suppose the "spaghetti-code" would be a real pain in this exercise?It looks like I have lost the ability to explain something in a few words, sorry xDDDD
After 150 pages, a little off-topic is going to disappear, then we can indulge in it for a few seconds.
As I said before, I didn't want to touch this game at all, because I felt that the GX4000 game is not a good game. And I only saw minimal graphical improvements and that is all.
But RedAngel saw something that I didn't, then I took a better look at it and I felt that this game could be converted to the classic CPCs without too many problems. And it is perfect, for everything that I have been talking about the first generation of gx4000 games: they were developed in a hurry and they started as classic cpc games.
Sure, after looking at that awful code, I thought of a few alternatives:
1.- I could port the zx version, all the logic is there and because it is not an advanced game, all the graphics could be improved to use mode 0. I even could use overscan or egx if I was crazy enough.
2.- Because the game logic is not complex and when I was a child and I saw the arcade, I made a few tests in basic using the cpc font as graphics. Well, 30 years later, sure that I would do that in assembly or even c in a few evenings. There are already two CPC games inspired in plotting; Inferno, a 1994 public domain game, it looks basic but it is in overscan; and Hot Plot, a type-in from a German magazine.
But after the first scary look, at the end of the day I don't need to touch that spaguetti code too much. In fact, Flipull+ is only redirecting a few of the bugged routines to my patched ones or they are patched directly.
The problem or blessing is that RedAngel had already revamped the graphics, adapted the nes levels and converted a lot of the new backgrounds. Starting a CPC version would mean remade everything again. And if I wanted to use all the backgrounds, I should load new backgrounds after a few levels or up the specification to 128 KBs machines or disk drives (neither of those things are bad, in fact in my mouse patches if I can, I use 128 KBs and floppy drive for hiscores, because if you have a mouse expansion, then you should have more expansions surely).
Then a CPC version is more than possible, the original cart organization is:
* Page 0: Game engine that it will go in $0000 and a few fonts (uncrunched)
* Page 1: Game engine that it will go in $8000 (includes bytes at 0 that are used as ram variables or working space when is copied to ram), game tiles (uncrunched)
* Page 2: Map, Fonts, logos, huds (everything uncrunched) and the menu code.
* Page 3: Sprites, fonts, other graphics (everything uncrunched)
* Page 4: Backgrounds 1-3
* Page 5: Backgrounds 4-6
* Page 6: Music player, song, ... and the last two backgrounds
* Page 7: Uncompressed loading screen
With that information, we can consider that for making a CPC 464 version, we should start by converting the loading screen into a real loading screen (we load and forget!), cart page 7 is not necessary anymore. Then we can put our video memory in $C000.
We are going to skip the backgrounds for now, that means cart pages 4, 5 and half of page 6 are not necessary anymore.
I am lazy, the menu sequence is going to be shown once; the first time, after the game is loaded, after that it will go out of the RAM.
Of course, I will not store the HUDs uncrunched, they would be drawn using tiles. And we don't need two copies of every tile; one when they are tiles and a second time when they are cpc+ hardware sprites. Meaning that I can put everything graphic related and the levels map, everything that lives in cart pages 2 and 3, now they will live in $4000. Surely, I can put the arkos player and the new songs in $4000 too.
Cart page 0 goes to $0000 and page 1 goes to $8000. The code changes that I need to do are: replace the cart pagination code, we can NOP those bytes, and CALL directly to our routines that are already in memory. And replace the routine that copies sprites to the sprites in the asic ram, for our sprite routines.
Now for extra credits, we can look for empty space in RAM for putting all the compressed backgrounds that we can get, and that is, you have Flipull for CPC.
... although if we have been making all this work, why should we be using the spaghetti code? The code necessary for handling this game is not hard. In fact it is a wonderful project for somebody that wants a funny project for a few months.
.
.
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@iXien, I hope that you are starting to enjoy the game, seriously, the more you play it, the better the game is, hehehe.
And you can return to the topic now!
#10
Technical support - Hardware related / Re: cable DDI-1 for CPC 6128
Last post by Rabs - Today at 13:15Would I be ok if I accidently got the cable upside down?