GBS-8220, 23DB Connectors and Leads

[Higgy]

Watch out @_dx you have not posted many times and you are asking us to donate 350$.
@dooklink who has done the most programming on the GBS is thinking you don't need a parallel programmer. Let us just wait. Plus it is Christmas!
Not many people are regularly posting on this thread so say paying 70$ towards a programmer is difficult and I could buy a few GBS for that amount.

@Voyager sorry I can't help as use 5v on my 8220. Try web search, there are quite a few reviews out there. They might mention PSU people have used. Could you hack a mobile phone charger? You can connect power via the barrel connector and there is also a small header nearby you can connect to.

[Stedy]

@voyager

Was your 12V supply a regulated output (check the label). The weak point on the GBS-8220 is the 1.8V regulator, it can accept maximum of 15V on the input. Some power supplies do not regulate properly off load and you could have fried the regulator. You might be lucky and replacing the 1117-3.3 regulator will recover the board.

I have a GBS-8200 which has switchmode regulator (more efficient) and works happily from a 12V netgear PSU.

@ _dx

Thanks for the link to the TVIA-5725 register list, it will come in handy.

If the MTV230M needs a parallel programmer, forget about using it. You would need to remove the device from the board to program it and need a DIP to PLCC adapter, never cheap.

It would be cheaper to create a 'leach board' using another Micro-controller, that sits over the top to send the TBD I2C commands required to tweak this design. An Arduino could also be used.

@dooklink

A Sony BVM monitor is kind bullet proof. I checked an online manual, the sync level can be 0.3 to 8V! Old CRT monitors/TVs used transistor circuits or 5V logic, newer tech uses 3.3V logic, which will not accept 5V signals, for long.

What systems are you trying to interface to?

There are some status registers in the TVIA-5725 worth monitoring, I'll experiment later today and post a list.

Off to the wokshop

Ian

Originally Posted by Higgy

Watch out @_dx you have not posted many times and you are asking us to donate 350$.
@dooklink who has done the most programming on the GBS is thinking you don't need a parallel programmer.

No problem buys, you don't know me and i understand why you worry about donate... It's absolutely normal.

I just can say that my personal problem with GBS will be solved using any popular MCU, without OSD and any other usefull features... When i think about public firmware with OSD - I think about all of GBS8200 users. Yes, it is possible to do it without parallel programmer, but this is not comfortable work enviroment... So if I think about community then community can pay back as donate for the tool. This is my position today.

Now you just know that there is some guy from Russia who can do the custom firmware with all 5725 features and this is good, because additional option is always better then nothing )

And You are right, now we have to wait @dooklink
At least he is ready to do the job without donate ))

[amigappc]

@_dx So what if we buy you programmer? We must send boards over so you could program chips? I am not sure you would done that for free? So if you are thinking of it, then invest in programmer, and charge for programming of chips in the future?

[kipper2k]

I hope this doesn't end up like the gotek where some people are charging ridiculous prices to program and do a $5 audio mod

[amigappc]

Well, @kipper2k seems like in Amiga community everyone is used to pay ridiculous prices. That is why everyone sees profit in a hobby projects.

Parallel programmer needed only for development process.
Developer works on new features, hitting the bugs... he needs much more reprogram iterations than someone can imagine. This is well known process with testing, debugging, writing new code. I just don't want to think about how not to brick another one GBS during one of the test runs, you know.. This sounds like hell )
You should know that ISP has one significant issue - one error and board is brickd, MTV chip goes to garbage! Because MTV230M ISP is software supported feature.
Yes it is possible to doulecheck everything before reflashing the chip, you can check some things in emulator... Yes it is possible and maybe someone can pass thru this hell - no problem, i will shake his hand in this case ))


Enduser can update firmware via ISP header because he don't need so much iterations, brick risk is minimal because both stock and custom firmwares are stable and firmware update method will be also tested and stable. So you don't need to send MTV chip or GBS board - you just plug wires to LPT or COM port and wait untill reflashing is complete)

This is my vision of how things should be done.

Also i think we can find many other GBS users who may be agree with donate, so we don't need to divide $350 by number of peoples in this thread )

Add: i just wanna free public GBS firmware and make this world slightly better. This is true, believe me or not

[amigappc]

@_dx, if that is the case, I would surely help, because having 30 USD scandoubler solution would be fantastic. Since programmer will stay yours after this process, maybe you should invest third and community the rest. How can we know you can achieve what you claim?

My name is Vasily, I am 28 years old guy from Crimea. I was born with keyboard in one hand and soldering iron in other
I can achieve the goal because I have some experience in embedded programming and developing custom devices from scratch.
Also i was involved in some projects as developer.
My programming experience started from school...
One of the most complicated projects was DSP related task in realtime voice coding on TI DSP. This project is private and i can't tell more details. I was involved as a programmer and job is done, everyone satisfied.

Last few years i working in automotive related area of electronics, so my hobby projects is automotive related too.

I have done some significant modifications of SECU-3 system http://secu-3.org/ to extend it's features for controlling methane-air mixture, not only the ignition itself. Here is the thread http://secu-3.org/forum/viewtopic.php?f=11&t=332
This mod is working every day on my father's car and he is very happy )

Currently i have my own, developed from scratch, little commercial project.
https://vk.com/vaz_cutoff
This tyny PCB costs $25. Almost like huge GBS ))
People are happy to buy it because there is no alternative in the world.
You even can see my nickname on the PCB.


I have publication about another project that i've done from scratch. Also automotive related.
http://habrahabr.ru/post/193892/


This is my hardware skills. Handmade 2layer PCB for SECU-3 project.
https://pp.vk.me/c317617/v317617995/...Dq4z5tjvGY.jpg
https://pp.vk.me/c317617/v317617995/...VIfOcxPyoE.jpg

I think i can achieve the goal anyway, no doubt.

I don't want to pay a third of programmers price because my contribution is my work. I think it will be much more expensive if you hire developer for this job ) So programmer will be a little bonus for me, not more.
You don't think it's fair enough?

[Stedy]

Hi,

I've resumed playing with the GBS-8200 board after a short break and the experiments continue. Could other users who have a GBS-8200 board and a Raspberry Pi connected, dump the I2C status registers from the device please?

The command is:

sudo i2cset -y -r 1 0x17 0xf0 0x00 b && sudo i2cdump -y -r 0-0x2f 1 0x17 b

You should get something like this:

Value 0x00 written, readback matched
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f    0123456789abcdef
00: a7 00 00 00 40 10 af e3 04 05 33 a3 1a 01 61 00    ?...@?????3???a.
10: 00 30 0c 00 00 18 02 bf 06 3b 00 40 01 00 00 00    .0?..????;.@?...
20: 00 00 04 0c 00 3c 00 00 00 00 00 00 00 00 e5 05    ..??.<........??

Oh if you try it, please detail what system you used. Non-Amiga settings welcome.

I want to understand what the TVIA-5725 thinks it is seeing first, before further work.

Switching off the de-interlacing, using dooklinks script works nicely to remove the fuzziness under the cursor. I still see some occassional speckles and there are noise patterns on a grey WB screen. With the right sampling settings, this should go.

Ian

[jbenam]

My GBS-8200 should be in the post today - if so I'll get the Pi up and running and dump the data you need.

If I can get some jumper wires

[Stedy]

@jbenam

Searching for Dupont connector:

http://www.ebay.co.uk/itm/20cm-DuPon...item27ecce7a8f

[Higgy]

Originally Posted by Stedy

Hi,

I've resumed playing with the GBS-8200 board after a short break and the experiments continue. Could other users who have a GBS-8200 board and a Raspberry Pi connected, dump the I2C status registers from the device please?

Ian

Will a GBS-8220 do?
Got Xmas presents to wrap, but I can't resist a bit of hacking

[Solo761]

Hmm, I could try to hook the two together. Maybe I'll find some time this weekend .

I used P11 connector on GBS board to connect Amiga to it. Unfortunately other platforms I have will have to wait as I'm currently moving to another place so all of my stuff is not available.

Just one question, from what I've read so far connecting Amiga directly to GBS is not healthy for GBS board. Unfortunately I have it connected just that way, simply wires from one connector to the other. So I need to add 680 ohm resistor to sync wire? Is this only thing needed or do R, G and B lines need to be "toned down".

Also, would it be also needed on Amiga to SCART cable when connecting to LCD TV? Your schematic has 330 Ohm resistor on sync line so that's how I made it.

[jbenam]

Originally Posted by Stedy

@jbenam

Searching for Dupont connector:

http://www.ebay.co.uk/itm/20cm-DuPon...item27ecce7a8f

Sadly with the Royal Mail completely slowed down by the amount of Xmas packages floating around I doubt I'll be able to get them in time...

I will have to build some in the office using wire and male headers, won't be nice-looking but it'll work

Also, I still haven't received my GBS-8200 I hope that it'll be in on Monday...

[Stedy]

@Higgy

Either board will do.

The GBS-8200 is a board with a single VGA output, switchmode converters, 5-12V input and is commonly labelled V4.
The GBS-8220 is a board with a dual VGA outputs linear converters, 5V input and is commonly labelled V3.

@Solo761

It was necessary to increase the resistor on the Sync output due to the different input circuit on the GBS-82XX board. 680 ohms is the minimum value.

RGB signals are fine, I've measured them at the device pins.

@jbenam

I hope your christmas present arrives

Ian

[Higgy]

@Stedy - I have some info.

AMIGA 1200 - data from top to bottom is for the follow resolutions:

640 x 256
320 x 256
320 x 512
1280 x 256

GBS-8220 running on option 1 (the only RGB option on GBS- / RPi controller

[dooklink]

RPi gbs_control users,

I've created some new settings for the raspi setup. These will be added to a 0.2 release on GitHub at some stage. For now I've attached them in a zip file.

If you want to use them copy them to /home/pi/settings/ via FTP.
If you can't use networking, then copy them to the SD fat partition then copy them across in the terminal

@Higgy I've made a few 800x600@60Hz RGBHV(VGA) modes for you to try. This should allow for the whole amiga screen to be shown. Can you try them?

[Higgy]

Good timing @dooklink I was just looking to put my RPi back into my bartop for Christmas. I will have a go at your new setting. Give me an hour.

[Higgy]

This is tough. I have 'interlace' mode working on some settings and not others. I have fuzziness under cursor with some modes, but then only on interlace.

Trying to work out the best way to test and to present findings.