picasso II only works with planar 16 colors

[oggie]

A3000 running 3.2.1 and p96 v3.2.4 drivers.

It works at any resolution as long as I pick (planar - 16 colors). If I choose any other color (tru color, high color etc) I get wavy or distorted lines on the screen.


You can see it here on the test image:
https://photos.app.goo.gl/P1KrVb74b7NU9BQD6

It's been suggested that I might have a bad ram chip? How would I even know what ram chip might be bad, if that's even the problem?

[Leon Besson]

What resolutions have you tried? Worth starting at 640x480.

The Picasso-II only has 2MB as well. So don’t be expecting big fantastic RTG resolutions.
I think the best you’ll get will be 1024x768.

[oggie]

I tried every resolution including 640x480

[Leon Besson]

The Picasso-II uses lates 80’s, early 90’s graphic chip. So 16-bit mode will probably be the best you’ll get with only 2MB RAM.
I take it it’s a new GBP-II card off EBay?

Check this link out. It can only manage 24-bit mode in 640x480;

https://bigbookofamigahardware.com/b...ct.aspx?id=466

[oggie]

Originally Posted by Leon Besson

The Picasso-II uses lates 80’s, early 90’s graphic chip. So 16-bit mode will probably be the best you’ll get with only 2MB RAM.
I take it it’s a new GBP-II card off EBay?

Check this link out. It can only manage 24-bit mode in 640x480;

https://bigbookofamigahardware.com/b...ct.aspx?id=466

But I can't even get it to do 16bit mode. With the settings I use, it's only 4bit.

I have no idea what you mean by "GBP-II card off ebay".

[oggie]

and, the setting I have working is 16 colors not 16 bit.

It's unusable with only 16 colors.

[Leon Besson]

Okay. So this is an original Picasso-II card then? The GBP-II I mention is a modern recreation of the Picasso II card using the same components which can be bought in kit form or made up on EBay.

If only 16 Colours on the screen as you say. You have made sure you have the correct drivers installed for the card? The monitor settings in Devs:monitors has been correctly setup?

You can download the drivers from this link;

http://amiga.resource.cx/exp/picasso2


That’s all I can offer on the subject Mang!

[oggie]

Yes, It's an original P2 card. And yes, I installed the latest picasso96 drivers.

[Leon Besson]

Originally Posted by oggie

Yes, It's an original P2 card. And yes, I installed the latest picasso96 drivers.

Okay. But you have installed the actual driver for the card? Picasso96 is not a driver as such. It’s more of a setup system.
Might be worth trying an older version of P96 off Aminet and the drivers from the link above to check.

[Jope]

Ok, let's hold up a minute here. P96 comes with a Picasso II driver that is selected at install time, and oggie should be using the one from the latest P96 package available to them.

The example picture's repetitive dot pattern looks like a hardware problem, perhaps a stuck bit in a ram chip or maybe some debris is shorting some signals together.

How to debug? Logic probe or oscilloscope perhaps. Or just replace all RAM chips blind, but this doesn't guarantee success if it ended up being something else than a bad RAM chip.

[zipper]

What about the jumper for segmented mode - does it have an effect?

[oggie]

changing the jumper made it worse.

I have a scope, but I'm not sure what I should be looking for,

I also have 256kx4 ram chips, but they're 80ns, not 45ns. I tried swapping them out, but it didn't make a difference.

[Thomas Richter]

Originally Posted by oggie

A3000 running 3.2.1 and p96 v3.2.4 drivers.

It works at any resolution as long as I pick (planar - 16 colors). If I choose any other color (tru color, high color etc) I get wavy or distorted lines on the screen.

Actually, I cannot see much on the picture as it is just blury. Wavy lines are typically an indication of some kind of interference problem, or a problem of the oscillator on the board, not being able to generate a stable frequency.



The PicassoII driver uses the Cirrus542x chip driver, and this one is stable. I'm testing it here on the GVP Spectrum (same chip), and it works nicely.


You can still buy the GBA PII++ (Matze's graphics card) from the Kryoflux store. It is based on a somewhat later Cirrus chip and also has a very robust and stable driver.

[oggie]

I wouldn't know how to determine what the problem on the board is unless I had some sort of guide to know what to look for when using a scope.

I'd rather keep this board and get it fixed versus buying another one.

[grelbfarlk]

What frequencies have you tried?
A good starting point to calculate the exact settings to put into Picasso96mode is this utility:
http://aminet.net/package/driver/video/umc
Start with something like: 1> UMC 640 480 60
Put those exact values in Picasso96mode and see what you get. If you get display, adjust frequencies and aspect and framing. Repeat for the next resolution.

[oggie]

Originally Posted by grelbfarlk

What frequencies have you tried?
A good starting point to calculate the exact settings to put into Picasso96mode is this utility:
http://aminet.net/package/driver/video/umc
Start with something like: 1> UMC 640 480 60
Put those exact values in Picasso96mode and see what you get. If you get display, adjust frequencies and aspect and framing. Repeat for the next resolution.

I'm just picking the default ones that are installed by the p96 driver.

[Thomas Richter]

Erase all settings for the Board. Create a new setting for this board with P96Mode, latest version. Attach the new settings to the board with the menu. Then select "Erase all" if P96Mode complains that some modes do not work. The modes you get then are those from VESA that are supposed to work on any monitor. You can still fine tune them. Do not overclock the board as this may not only generate such "wavy lines" if the chip is beyond limits, it may also damage the chip.

[oggie]

I tried using umc and generated a 640x480 config. It doesn't seem to matter what setting I chose, I always get some sort of weird artifact. In the attached image, the window title bar has red and green dots (look next to the words 'in use'). Then beside the scroll bar, you can see the red dots.

[Thomas Richter]

This looks like bad RAM/defect hardware.

[oggie]

I don't see any bad components or traces under a microscope.
I also swapped out the ram and the problem didn't go away.