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| VG8235 with broken S3527 - Any workaround?
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Alexandre_Taito msx freak Berichten: 183 | Geplaatst: 19 December 2004, 15:49   |
Hi everyone, This is my first post, I'm Alexandre from Brazil. I use to develop many kinds of interesting hardware for computers and videogames, I'd suggest you to take a look at my page www.tabajara-labs.com.br for some funny electronics stuff
After the introduction, here we go.
I got my first MSX2 Computer yesterday, a Philips VG8235. I could put everything working, since it was broken, but one thing I cannot go further - the first trigger of the first joystick is permanently pressed.
The circuit is simple. Coming from the pin 5 of the first joystick connector, we have a pull-up resistor before a small transistor and so it goes to pin 52 of the S3527 MSX engine. The MSX engine pin keeps on around 0.7V, and pulling it out of the board does not help either. Seems that someone tried to use a msxnet cable improperly done, or some high voltage was applied to this pin. The result: I cannot play ANY games on this machine.
My questions are:
- Is there a workaround to this problem? The S3527 is broken!
- Can someone help me in finding a new/used S3527 chip overseas, since in Brazil these are just IMPOSSIBLE to come by?
Thanks a lot,
Alexandre Souza
Vila Velha, ES - Brazil |
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Repair-Bas msx addict Berichten: 388 | Geplaatst: 19 December 2004, 16:54   |
I have those chips in stock
New and used
I have also lots of new prints for the 8235
If you want only the s3527 I have it for you for free
Please mail me: kornalijnslijper@quicknet.nl
Only shippingcosts are for you |
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Sonic_aka_T
 msx guru Berichten: 2269 | Geplaatst: 20 December 2004, 02:23   |
That's the Christmas Spirit I like to see!  |
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Alexandre_Taito msx freak Berichten: 183 | Geplaatst: 20 December 2004, 04:22   |
So do I  Some things that are common overseas, are incredible RARE in Brazil. And unfortunately, this is a problem I cannot see a logic workaround...Repair-Bas will be of great help, the 8235 is already fitted with a 31/2 720K internal drive, and I'm planning which mapper size I'll install. Will keep everything ready just waiting for the MSX Engine. Ah, I have proper equipment for SMD reworking, so be safe the Msx-engine will be kindly cared
Greetz from Brazil! |
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Alexandre_Taito msx freak Berichten: 183 | Geplaatst: 04 Januari 2005, 09:21   |
Repair-Bas, did you got my e-mail? I've sent you my adress, but got no answer from you...
My adress:
Alexandre D. F. Souza
Rua Dr. Afonso Schwab 713 - Guaranhuns
Vila Velha - ES - 29103-680 - Brazil
Thanks a lot!!! I'm looking for this chip, I'm crazy to use my MSX2 
Alexandre |
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Repair-Bas msx addict Berichten: 388 | Geplaatst: 04 Januari 2005, 12:44   |
It is shipped today
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Repair-Bas msx addict Berichten: 388 | Geplaatst: 20 Januari 2005, 17:17   |
and now I am waiting!!!
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Alexandre_Taito msx freak Berichten: 183 | Geplaatst: 15 Januari 2006, 04:46   |
Still waiting...
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Sonic_aka_T
 msx guru Berichten: 2269 | Geplaatst: 15 Januari 2006, 16:21   |
I have one for you, if you want. I think I also said this in another thread about the same issue. The only 'fear' I have is about you soldering an SMD component like that. Are you sure you're up for the challenge? It's really not something that should be taken lightly...
Anyhoo, if you want I can cut it out of an old VG8220 I have around here somewhere. I'd rather not desolder the engine myself, since I'll prolly end up breaking off some of those tiny pins, so I could just cut out part of the print. If you really want it, I could figure out what the postage would be and you could wire it to me or something.
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Grauw msx professional Berichten: 1006 | Geplaatst: 15 Januari 2006, 17:38   |
I have the same problem on one of my MSXes. It’s a VG8235, too.
~Grauw
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Alexandre_Taito msx freak Berichten: 183 | Geplaatst: 15 Januari 2006, 20:30   |
Sonic, as I said before, I'm used to solder SMD devices way bigger than the S3527. If you can supply it I'd be more than grateful. Please contact me in private so we can discuss what to do. And thanks a lot! I can't wait to see my 8235 working
BTW, when the VG8235 will be properly working, I'll do a full report page with everything that happened to make it work, and maybe a good SMD soldering tutorial. Maybe MSX people needs that  |
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Alexandre_Taito msx freak Berichten: 183 | Geplaatst: 15 Januari 2006, 20:52   |
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Sonic_aka_T
 msx guru Berichten: 2269 | Geplaatst: 17 Januari 2006, 03:04   |
I don't MSN very often anymore, do you have a mail address?
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Alexandre_Taito msx freak Berichten: 183 | Geplaatst: 17 Januari 2006, 03:24   |
yes, send to msx (@) tabajara-labs (.) com (.) br
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