Problem with RGBS out to a GBS.

MrSiggler · 16 January 2014, 23:03

Hey all,

I've recently gotten a PAL Amiga from the Netherlands, and am trying to get it in a usable state here in North America.. I overcame the first problem of power, by modding in a PicoPSU.. it fires up no problem(as far as I can tell).

For video, I got an RGB Scart cable from amigakit, but have been completely unable to get it to sync with the gbs 8220. I've tried with the scart cable, both with and without an lm1881 circuit on the sync line, I've tried running the signals directly from the db23 port to the gbs, and I get the same result.

I get one of two things.. on rare occasion, I see the kickstart screen, but it's garbled, and frozen, changing it's garbled state maybe once every 4 seconds or so.. but most of the time, I get a green, rapidly wavering, flickering screen. I do get a stable, but black and white image from the mono port, however.. I've tried two different GBS boards as well..

I see posts here, and other places saying the gbs 8220 does work with PAL Amigas.. but some others saying it doesn't..

Has anyone tried, specifically, an Amiga 500 revision 5 with an Agnus 8371? Or have any suggestions? I'm at a loss here as to what else I can try.

Many thanks!

AmmoJammo · 16 January 2014, 23:19

Got any pics of everything? (half for interest, half to help)

There's no reason it won't work, being a PAL machine doesn't matter, and I don't see the fact that its a Rev5 effecting it at all either.

Have you tried holding the "auto" button on the GBS? it normally gets the image displaying... you just hold the "down" button for 3-5seconds, when released, the led will flash, from memory..

MrSiggler · 16 January 2014, 23:26

I've tried that yeah. I've noticed that I tend to get the green garbly more on 800x600 and up, and the broken kickstart on 640x480. I'll take some pictures later on.

AmmoJammo · 16 January 2014, 23:37

You are using composite sync right? not separate horizontal and vertical?

MrSiggler · 16 January 2014, 23:52

Indeed, pin 10 on the DB23 connector (which is also what the scart cable uses)

When I ran the signal directly to the gbs from the port.. I used pins 3, 4, 5 as RGB, pin 10 for sync, and pin 16 for ground.. and I ran them to the big metal RGBS connector, bottom left of the GBS, where a JAMMA connector would go.

I also tried using the mono video for sync, both with and without the lm1881 circuit.. same results as the csync line on the video port.

MrSiggler · 24 January 2014, 03:04

I'm still not able to get any sync. I used a tool to get my Dreamcast to run some games in 50hz, and the GBS accepted the signal okay, so that doesn't seem to be the problem..

Assuming that there's a problem with the Amiga itself, and not the GBS being picky... if the mono port's video looks fine, but the RGB video/sync from the video port is off, any suggestions on what to look for?

kipper2k · 24 January 2014, 03:21

Quote:

Originally Posted by MrSiggler

Indeed, pin 10 on the DB23 connector (which is also what the scart cable uses)

When I ran the signal directly to the gbs from the port.. I used pins 3, 4, 5 as RGB, pin 10 for sync, and pin 16 for ground.. and I ran them to the big metal RGBS connector, bottom left of the GBS, where a JAMMA connector would go.

I also tried using the mono video for sync, both with and without the lm1881 circuit.. same results as the csync line on the video port.

You should also ground pins 17, 18, 19 and 20

amiman99 · 24 January 2014, 17:38

I had some problems with PAL some time ago, so I made a small txt file for my reference on how to get the GBS working on Amiga.

Here are some settings that worked for me, both in PAL and NTSC.

HPOS 56
VPOS 16
HSIZE 48
VSIZE 55
CLAMP ST 97
CLAMP SD 00

or

HPOS 50
VPOS 14
HSIZE 50
VSIZE 56
CLAMP ST 97
CLAMP SD 00

These settings work in
PAL and NTSC.
Good luck.

The converter is labeled pretty good
All pins are on Amiga side:

PIN 3 RED
PIN 4 GREEN
PIN 5 BLUE
PIN 10 CSYNC
PIN 19 GND

Edit: I for got to add that PAL may need or look better at 800x600 resolution.

MrSiggler · 24 January 2014, 18:07

Thanks for those values.. I tried them, but got no result

I also tried twisting all the grounds together as suggested by kipper, but no change..

When in 640x480 in the gbs, I do see the amiga's output, but it updates about every 5 seconds, and is all broken up. When I move to 800x600 or higher, I get nothing but what is best described as the snow you'd see on an old CRT..

amiman, do you happen to recall the coast st/such values you had under the picture menu for the amiga?

amiman99 · 24 January 2014, 19:23

Quote:

Originally Posted by MrSiggler

...
amiman, do you happen to recall the coast st/such values you had under the picture menu for the amiga?

Can rephrase that, I'm not sure what are you looking for?

MrSiggler · 24 January 2014, 19:54

Quote:

Originally Posted by amiman99

Can rephrase that, I'm not sure what are you looking for?

Sorry, I meant on the GBS. In the Picture menu there are two Coast settings, like the Clamps in Geometry. Did you have to adjust those as well?

amiman99 · 25 January 2014, 02:42

Quote:

Originally Posted by MrSiggler

Sorry, I meant on the GBS. In the Picture menu there are two Coast settings, like the Clamps in Geometry. Did you have to adjust those as well?

I took mine apart so I can access the menu and I don't see any COAST settings. Maybe different version??? Mine is v4.0

MrSiggler · 25 January 2014, 18:33

Thanks for checking! Mine is a version 3 8220.

A few random notes... While I get that static on 800x600+, I've noticed that if I unplug ground, I get the same sort of jumpy picture as I do when it's in 640x480.. so visually it's almost as if it slightly improves with no ground attached.. but that can't be right?

I'm kinda grasping at straws here now.

Any suggestions on other devices to try for getting video out of this Amiga? Or to verify the signals, somehow? It almost seems like the cases where I get the static, is where the picture *should* be there, 800x600+, and only after setting auto.. and it goes to the jerky/jumpy but slightly visible if I remove the ground line.

amiman99 · 26 January 2014, 05:55

Some people reported better results with SCART to HDMI converter with Amiga, and they are pretty cheap on Ebay.
As far as GBS, it took me awhile to get the PAL screen working, but fiddling with the GBS setup I was able to get it working.
The problem I had with PAL was that when I changed the resolution from NTSC to PAL, it would appear to freeze and change the desktop color to green, but the very top portion of the screen would work.
I played with the CLAMP settings and one day I found the sweet spot and it works.
The problem with GBS is that PERFECT setup for NTSC will not work with PAL, so you need to find a middle ground.
The pin out I gave you are correct, so it should work.
Can you post a screenshot?

roy bates · 26 January 2014, 12:13

how have you got it connected up,inputs on the gbs etc?

a picture of the wiring might help.

MrSiggler · 26 January 2014, 18:24

Quote:

Originally Posted by roy bates

how have you got it connected up,inputs on the gbs etc?

a picture of the wiring might help.

I made a quick video showing how I've got it hooked up, and what I see on the screen. I didn't fiddle with the gbs settings any, but what you see, is the best I can get. It's either that, or "no signal" from the gbs. Broken image in 64x480, or static/snow in higher resolutions. When I move through the h/v size in Geometry, the static does change, so it's not pure garbage going through.

[ Show youtube player ]

Stedy · 27 January 2014, 00:19

@MrSiggler

You have connected the analogue RGB output of the Amiga to the digital CGA/EGA input of the GBS8220. You need to use the 8 pin P11 connector.

When you use the P11 connector, you can still supply CSYNC from pin 10 of the Amiga or use the separate HSYNC and VSYNC signals.

Ian

MrSiggler · 27 January 2014, 00:58

Ah, I didn't realize there was a difference in those plugs. However, when I plugged the P11 connector in, and moved my clips to those wires.. putting the csync to the hsync line, I got the same garbled image. Via vsync I got a "no signal" message.. I'll try using separate h/v from the amiga instead of comp sync.

MrSiggler · 27 January 2014, 01:14

I don't seem to get any picture at all (though it doesn't complain about lack of signal) when using h/v.. I used pins 11 and 12 of the DB23 connector as H/V, wired to the appropriate wire on the P11 connector, switched the GBS to RGBHV mode.. and tried fiddling with the menus.. (when in rgbhv mode, the geometry menu isn't accessible?)

Are there GBS versions out there that can't be used with the Amiga?

kipper2k · 27 January 2014, 01:18

Quote:

Originally Posted by MrSiggler

I don't seem to get any picture at all (though it doesn't complain about lack of signal) when using h/v.. I used pins 11 and 12 of the DB23 connector as H/V, wired to the appropriate wire on the P11 connector, switched the GBS to RGBHV mode.. and tried fiddling with the menus.. (when in rgbhv mode, the geometry menu isn't accessible?)

Are there GBS versions out there that can't be used with the Amiga?

I've had it working before, using RGB, CSync (pin 10), +5v (pin 23) and ground (Pins 16, 17, 18, 19 and 20

16 January 2014, 23:03	#1
MrSiggler Users Awaiting Email Confirmation Join Date: Jan 2014 Location: Canada Posts: 24	Problem with RGBS out to a GBS. Hey all, I've recently gotten a PAL Amiga from the Netherlands, and am trying to get it in a usable state here in North America.. I overcame the first problem of power, by modding in a PicoPSU.. it fires up no problem(as far as I can tell). For video, I got an RGB Scart cable from amigakit, but have been completely unable to get it to sync with the gbs 8220. I've tried with the scart cable, both with and without an lm1881 circuit on the sync line, I've tried running the signals directly from the db23 port to the gbs, and I get the same result. I get one of two things.. on rare occasion, I see the kickstart screen, but it's garbled, and frozen, changing it's garbled state maybe once every 4 seconds or so.. but most of the time, I get a green, rapidly wavering, flickering screen. I do get a stable, but black and white image from the mono port, however.. I've tried two different GBS boards as well.. I see posts here, and other places saying the gbs 8220 does work with PAL Amigas.. but some others saying it doesn't.. Has anyone tried, specifically, an Amiga 500 revision 5 with an Agnus 8371? Or have any suggestions? I'm at a loss here as to what else I can try. Many thanks!

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16 January 2014, 23:19	#2
AmmoJammo Registered User Join Date: Nov 2012 Location: Adelaide, Australia Posts: 57	Got any pics of everything? (half for interest, half to help) There's no reason it won't work, being a PAL machine doesn't matter, and I don't see the fact that its a Rev5 effecting it at all either. Have you tried holding the "auto" button on the GBS? it normally gets the image displaying... you just hold the "down" button for 3-5seconds, when released, the led will flash, from memory..

16 January 2014, 23:26	#3
MrSiggler Users Awaiting Email Confirmation Join Date: Jan 2014 Location: Canada Posts: 24	I've tried that yeah. I've noticed that I tend to get the green garbly more on 800x600 and up, and the broken kickstart on 640x480. I'll take some pictures later on.

16 January 2014, 23:37	#4
AmmoJammo Registered User Join Date: Nov 2012 Location: Adelaide, Australia Posts: 57	You are using composite sync right? not separate horizontal and vertical?

16 January 2014, 23:52	#5
MrSiggler Users Awaiting Email Confirmation Join Date: Jan 2014 Location: Canada Posts: 24	Indeed, pin 10 on the DB23 connector (which is also what the scart cable uses) When I ran the signal directly to the gbs from the port.. I used pins 3, 4, 5 as RGB, pin 10 for sync, and pin 16 for ground.. and I ran them to the big metal RGBS connector, bottom left of the GBS, where a JAMMA connector would go. I also tried using the mono video for sync, both with and without the lm1881 circuit.. same results as the csync line on the video port.

24 January 2014, 03:04	#6
MrSiggler Users Awaiting Email Confirmation Join Date: Jan 2014 Location: Canada Posts: 24	I'm still not able to get any sync. I used a tool to get my Dreamcast to run some games in 50hz, and the GBS accepted the signal okay, so that doesn't seem to be the problem.. Assuming that there's a problem with the Amiga itself, and not the GBS being picky... if the mono port's video looks fine, but the RGB video/sync from the video port is off, any suggestions on what to look for?

24 January 2014, 17:38	#8
amiman99 Registered User Join Date: Sep 2009 Location: San Antonio, TX USA Age: 50 Posts: 1,185	I had some problems with PAL some time ago, so I made a small txt file for my reference on how to get the GBS working on Amiga. Here are some settings that worked for me, both in PAL and NTSC. HPOS 56 VPOS 16 HSIZE 48 VSIZE 55 CLAMP ST 97 CLAMP SD 00 or HPOS 50 VPOS 14 HSIZE 50 VSIZE 56 CLAMP ST 97 CLAMP SD 00 These settings work in PAL and NTSC. Good luck. The converter is labeled pretty good All pins are on Amiga side: PIN 3 RED PIN 4 GREEN PIN 5 BLUE PIN 10 CSYNC PIN 19 GND Edit: I for got to add that PAL may need or look better at 800x600 resolution.

24 January 2014, 18:07	#9
MrSiggler Users Awaiting Email Confirmation Join Date: Jan 2014 Location: Canada Posts: 24	Thanks for those values.. I tried them, but got no result I also tried twisting all the grounds together as suggested by kipper, but no change.. When in 640x480 in the gbs, I do see the amiga's output, but it updates about every 5 seconds, and is all broken up. When I move to 800x600 or higher, I get nothing but what is best described as the snow you'd see on an old CRT.. amiman, do you happen to recall the coast st/such values you had under the picture menu for the amiga?

25 January 2014, 18:33	#13
MrSiggler Users Awaiting Email Confirmation Join Date: Jan 2014 Location: Canada Posts: 24	Thanks for checking! Mine is a version 3 8220. A few random notes... While I get that static on 800x600+, I've noticed that if I unplug ground, I get the same sort of jumpy picture as I do when it's in 640x480.. so visually it's almost as if it slightly improves with no ground attached.. but that can't be right? I'm kinda grasping at straws here now. Any suggestions on other devices to try for getting video out of this Amiga? Or to verify the signals, somehow? It almost seems like the cases where I get the static, is where the picture should be there, 800x600+, and only after setting auto.. and it goes to the jerky/jumpy but slightly visible if I remove the ground line.

26 January 2014, 05:55	#14
amiman99 Registered User Join Date: Sep 2009 Location: San Antonio, TX USA Age: 50 Posts: 1,185	Some people reported better results with SCART to HDMI converter with Amiga, and they are pretty cheap on Ebay. As far as GBS, it took me awhile to get the PAL screen working, but fiddling with the GBS setup I was able to get it working. The problem I had with PAL was that when I changed the resolution from NTSC to PAL, it would appear to freeze and change the desktop color to green, but the very top portion of the screen would work. I played with the CLAMP settings and one day I found the sweet spot and it works. The problem with GBS is that PERFECT setup for NTSC will not work with PAL, so you need to find a middle ground. The pin out I gave you are correct, so it should work. Can you post a screenshot?

26 January 2014, 12:13	#15
roy bates Registered User Join Date: Apr 2011 Location: birmingham Age: 55 Posts: 2,827	how have you got it connected up,inputs on the gbs etc? a picture of the wiring might help.

27 January 2014, 00:19	#17
Stedy Registered User Join Date: Jan 2008 Location: United Kingdom Age: 46 Posts: 735	@MrSiggler You have connected the analogue RGB output of the Amiga to the digital CGA/EGA input of the GBS8220. You need to use the 8 pin P11 connector. When you use the P11 connector, you can still supply CSYNC from pin 10 of the Amiga or use the separate HSYNC and VSYNC signals. Ian

27 January 2014, 00:58	#18
MrSiggler Users Awaiting Email Confirmation Join Date: Jan 2014 Location: Canada Posts: 24	Ah, I didn't realize there was a difference in those plugs. However, when I plugged the P11 connector in, and moved my clips to those wires.. putting the csync to the hsync line, I got the same garbled image. Via vsync I got a "no signal" message.. I'll try using separate h/v from the amiga instead of comp sync.

27 January 2014, 01:14	#19
MrSiggler Users Awaiting Email Confirmation Join Date: Jan 2014 Location: Canada Posts: 24	I don't seem to get any picture at all (though it doesn't complain about lack of signal) when using h/v.. I used pins 11 and 12 of the DB23 connector as H/V, wired to the appropriate wire on the P11 connector, switched the GBS to RGBHV mode.. and tried fiddling with the menus.. (when in rgbhv mode, the geometry menu isn't accessible?) Are there GBS versions out there that can't be used with the Amiga?

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