News:

Printed Amstrad Addict magazine announced, check it out here!

Main Menu

Graphics card for CPC.

Started by steve, 19:30, 10 October 14

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Bryce

None of these ideas will solve the main problem. These cards need massive amounts of data sent to them. Even with dualport RAM, FPGAs or anything else, the Z80 just isn't fast enough to feed a serious graphics card. It's difficult enough to manage a 16K screen and juggle gameplay code at the same time. Even if you "just" went up to 128K screens (still well within 90's technology), the CPU wouldn't cope.

Bryce.

Prodatron

The amount of data itself is not a problem. If you have a mass storage device it only takes less than 10 seconds to transfer 1MB. Well, I don't know about what video specs you are speaking :D It should still look a little bit realistic.
But once the data is on the card the Z80 is doing nothing else than sending some coordinates to the VDP. The V9990 demonstrated it already in a very impressive way, that such advanced graphic modes are possible on 8bit machines.

GRAPHICAL Z80 MULTITASKING OPERATING SYSTEM

Bryce

So really we should be looking at mass storage solutions first and then worry about graphic cards?

Bryce.

CraigsBar

Quote from: Bryce on 13:18, 14 October 14
So really we should be looking at mass storage solutions first and then worry about graphic cards?

Bryce.
oh yes. A dual sd card, rtc and mouse interface for the mother x4 please.
IRC:  #Retro4All on Freenode

CraigsBar

Quote from: CraigsBar on 13:27, 14 October 14
oh yes. A dual sd card, rtc and mouse interface for the mother x4 please. :-)
IRC:  #Retro4All on Freenode

Prodatron

Quote from: Bryce on 13:18, 14 October 14
So really we should be looking at mass storage solutions first and then worry about graphic cards?

There should be about 200 SYMBiFACE II cards around :P I hope there will be a successor available at some day.
I am currently working on HxC native SD card support for SymbOS. As soon as this is working every HxC owner will have a FAT32 mass storage with up to 32GB which is accessible at a reasonable speed.

Quote from: CraigsBar on 13:27, 14 October 14
oh yes. A dual sd card, rtc and mouse interface for the mother x4 please.

I absolutely agree! :)

GRAPHICAL Z80 MULTITASKING OPERATING SYSTEM

Bryce

Quote from: Prodatron on 13:35, 14 October 14
There should be about 200 SYMBiFACE II cards around :P I hope there will be a successor available at some day.
I am currently working on HxC native SD card support for SymbOS. As soon as this is working every HxC owner will have a FAT32 mass storage with up to 32GB which is accessible at a reasonable speed.

Does this have to be embedded in SymbOS? Wouldn't it be possible to make it accessable through BASIC from a standard expansion ROM?

Bryce.

CraigsBar

Quote from: Prodatron on 13:35, 14 October 14
There should be about 200 SYMBiFACE II cards around :P I hope there will be a successor available at some day.
I am currently working on HxC native SD card support for SymbOS. As soon as this is working every HxC owner will have a FAT32 mass storage with up to 32GB which is accessible at a reasonable speed.

I absolutely agree! :)
then I will be buying another hxc lol.
IRC:  #Retro4All on Freenode

Prodatron

Quote from: Bryce on 13:57, 14 October 14
Does this have to be embedded in SymbOS? Wouldn't it be possible to make it accessable through BASIC from a standard expansion ROM?
The question is: When will we have FAT support in Amsdos? There were already several attemps like SymDos, but unfortunately nothing has been finished during the last 10 years, after the CPC-IDE 1 has been released.
On the XzentriX 2014 party I had a look at an alpha-version of a FAT16 implementation for Amsdos. I really hope that this project will be finished. That would mean that FAT-storages are finally accessible outside SymbOS, too.

GRAPHICAL Z80 MULTITASKING OPERATING SYSTEM

Prodatron

Quote from: CraigsBar on 14:18, 14 October 14
then I will be buying another hxc lol.
If you already have one, it should be enough. It should be possible to access a disc image (e.g. as drive B) and the native SD card (e.g. as drive C) at the same time.
Ops, we are a little bit off-topic now...

GRAPHICAL Z80 MULTITASKING OPERATING SYSTEM

CraigsBar

Quote from: Prodatron on 14:26, 14 October 14
If you already have one, it should be enough. It should be possible to access a disc image (e.g. as drive B) and the native SD card (e.g. as drive C) at the same time.
Ops, we are a little bit off-topic now...
heading more off topic now.... I will need one for my 6128plus, the one I have . And a second one for my 4128plus when I get it back from Bryce.
IRC:  #Retro4All on Freenode

TFM

Quote from: Prodatron on 13:35, 14 October 14
I am currently working on HxC native SD card support for SymbOS. As soon as this is working every HxC owner will have a FAT32 mass storage with up to 32GB which is accessible at a reasonable speed.


How quick would it be? Floppy-like speed or faster?
TFM of FutureSoft
Also visit the CPC and Plus users favorite OS: FutureOS - The Revolution on CPC6128 and 6128Plus

Bryce

Quote from: TFM on 19:12, 14 October 14

How quick would it be? Floppy-like speed or faster?

Well the HxC would still need to be connected to the FDC I assume. So it couldn't be much faster than floppy speed.

Bryce.

Munchausen

#63
I think it goes at up to 250Kbps... supposedly the HxC can go up to 500Kbps though, so either way it isn't exactly slow (for a Z80 mass storage solution anyway). I don't think it is going to be slowing you down too much.

Bryce

Yes, but to get the CPCs FDC to deliver/read 500Kbps would require hardware changes inside the CPC.

Bryce.

Prodatron

- The theoretical maximum speed for any I/O-transfer is about 200KB/s for the CPC (using INI:INI:INI:... and beeing able to use up to 256 sequently port addresses for the data).
- If you have one port for the data, the maximum speed is about 160KB/s (like we have with the SYMBiFACE II).

Regarding the FDC and the HxC I currently have no idea how the HxC behaves while transfering one sector. Usually there is a delay between two bytes because of the rotating speed of the disc drive. So after each byte you always have to check, if the next byte is available, which would decrease the maximum speed down to something like maybe 45KB/s (after transfering 8 sectors you always have to write a control sector for setting the new LBA).
If the HxC doesn't emulate a delay between each byte you could reach really high transfer rates on the CPC, too.
But let's see...

CU,
Prodatron

GRAPHICAL Z80 MULTITASKING OPERATING SYSTEM

TFM

It does matter what the HxC does of course. But the FDC is the critical component. It has it's own timing dependent on the frequency it runs with (for the FDC765 this is typically 4 MHz or 8 MHz). Gaps need to be considered and the data transfer protocol too. It does not matter if you poll or use interrupt controlled I/O, the speed is the same, because it depends on the FDC.


Even with the fastest disc routines the FDC will never be as quick as a HD. I used FutureOS to assess the HxC and yes, when using the right format it can be faster than a real floppy disc drive (of course). But I really wouldn't call the difference in speed worth to be mentioned here. We talk in orders of magnitude, nobody is interested in a couple of percent speed up.


So let the HD do what the HD is for.   :laugh: :) :)
TFM of FutureSoft
Also visit the CPC and Plus users favorite OS: FutureOS - The Revolution on CPC6128 and 6128Plus

Prodatron

HxC direct access in SymbOS is alive!!  :P :P

[attach=2]

So we have another 32GB FAT32 mass storage device available for the CPC now :)
Have to fix some bugs now...

CU,
Prodatron

GRAPHICAL Z80 MULTITASKING OPERATING SYSTEM

TFM

Well done! And quick too!  :) :) :)


Can you tell us something about the data transfer rate when using direct FAT access?
TFM of FutureSoft
Also visit the CPC and Plus users favorite OS: FutureOS - The Revolution on CPC6128 and 6128Plus

Neil79

Ooh tell me more!


So it runs from a HxC, like an OS?
The latest in Indie & Retro News!!! IndieRetroNews - Indie Retro News on twitter

Prodatron

Quote from: Neil79 on 21:44, 16 October 14So it runs from a HxC, like an OS?
In SymbOS you can access the SD card in your HxC device directly.
Example:
- you have a CPC6128 with an internal 3" drive (which is drive A)
- now you add the HxC as the external disc drive (which is drive B)
- the HxC is using an SD card for storing all disc images; but the SD card for the HxC itself is a FAT32 mass storage and can have a capacity up to 32GB - so why not using it for direct access, too?

Now SymbOS can add the SD card of the HxC directly as a new device for the CPC. So you usually have drive A+B as (HxC-emulated) disc drives and drive C as the complete SD card with FAT32, subdirectories etc...

CU,
Prodatron

GRAPHICAL Z80 MULTITASKING OPERATING SYSTEM

Munchausen

Quote from: Prodatron on 20:57, 16 October 14
HxC direct access in SymbOS is alive!!  :P :P

[attach=2]

So we have another 32GB FAT32 mass storage device available for the CPC now :)
Have to fix some bugs now...

CU,
Prodatron


Awesome news! And this means a mass storage solution for the PCW machines has arrived too!

zhulien

Quote from: Prodatron on 22:40, 16 October 14
In SymbOS you can access the SD card in your HxC device directly.
Example:
- you have a CPC6128 with an internal 3" drive (which is drive A)
- now you add the HxC as the external disc drive (which is drive B)
- the HxC is using an SD card for storing all disc images; but the SD card for the HxC itself is a FAT32 mass storage and can have a capacity up to 32GB - so why not using it for direct access, too?

Now SymbOS can add the SD card of the HxC directly as a new device for the CPC. So you usually have drive A+B as (HxC-emulated) disc drives and drive C as the complete SD card with FAT32, subdirectories etc...

CU,
Prodatron


If we have an internal drive replacement HxC and a drive B HxC and an M4, do we get 3 mass storage devices at once?

Prodatron

Quote from: Munchausen on 06:42, 17 October 14Awesome news! And this means a mass storage solution for the PCW machines has arrived too!
Yes, finally HxC direct SD card support has been added to SymbOS PCW last month :) It will be available in the next release.

Quote from: zhulien on 05:21, 01 November 17If we have an internal drive replacement HxC and a drive B HxC and an M4, do we get 3 mass storage devices at once?
FDC support and the HxC direct SD card access are implemented in the same driver. So yes, e.g. with the M4Board driver you have Floppy, SD card HxC and MicroSD card M4Board access at the same time.
(still very offtopic)

GRAPHICAL Z80 MULTITASKING OPERATING SYSTEM

zhulien

Quote from: Prodatron on 19:07, 01 November 17
Yes, finally HxC direct SD card support has been added to SymbOS PCW last month :) It will be available in the next release.
FDC support and the HxC direct SD card access are implemented in the same driver. So yes, e.g. with the M4Board driver you have Floppy, SD card HxC and MicroSD card M4Board access at the same time.
(still very offtopic)


Is it totally off topic?  we are talking drives... ram drives are what the gfx card is for if not being used as a gfx card  :D

Powered by SMFPacks Menu Editor Mod