Posted By
DeadTED
on 2013-02-13
22:22:19
|  Dead TEDs and plus 4 keyboard
Hi all, I recently decided to clean the keyboard of my 3 plus 4s as the keys were sticky, and it was downhill from there.
After cleaning and reassembling I noticed that some keys were not working at all then, TED started being silly. Cut a long story short I fried 3 TEDs. Couple of questions.
1. Can the keyboard or faulty 6529b kill TED? If so what can be done to avoid this?
2. Is anyone ingested in creating an FPGA replacement for TED, I would be willing to provide some funding, as I love my plus 4s and use them mainly for hardware interfacing primarily as a hobby. Btw I also have 3 dead c16s. Only one plus 4 barely alive, and one c116 which I dare not turn on, as it is my favourite machine.
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Posted By
MIK
on 2013-02-14
05:03:26
 | Re: Dead TEDs and plus 4 keyboard
I've never known a kyboard to kill TED but I guess it's possible, but in all honesty there is nothing too them...
As you say you love plus/4's does this mean you have more than 1? Why not take a Keyboard out of a spare one, or buy a dead Plus/4 just for the keyboard.
Maybe you have seen this but this is just a quick guide on how to clean a keyboard. Normally keys that don't work DO, they just have dirty contacts.
http://plus4world.powweb.com/plus4encyclopedia/500009
If one mother board keeps killing Ted then there must be something else major wrong with it to do this... Joyports can also damage TED if you use one that was not designed for it such as a Sega Control pad...
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Posted By
DeadTED
on 2013-02-14
07:37:06
| Re: Dead TEDs and plus 4 keyboard
Hi MIC, yeah I have 3 plus 4 consoles all now dead as of last night. I also have 3 c16s which are also dead!
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Posted By
crock
on 2013-02-14
11:53:04
 | Re: Dead TEDs and plus 4 keyboard
I have never known a faulty 6529 kill a TED but I have killed the latch on a TED by accidentally shorting the outputs of the 6529. The fragility of the latch on the TED is well documented, along with the contributing factors which, as MIK said, include anything but simple 5 pole joysticks. The joysticks and the keyboard are wired together and both feed the latch on the TED in the 264 machines, the only difference is that the 6529 provides the input for the keyboard, and a buffered data line provides the input for the joysticks. What is less well understood is quite *why* these cause the TED to fail.
If the latch is damaged though, it's usually only the joysticks which fail to respond properly, the keyboard and other functions survive. In what way have your TED's died? Black screen or just a non responsive keyboard? If it's all three +4's, have you ruled out the power supply as a cause?
Rob
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Posted By
Hans
on 2013-02-14
13:54:06
| Re: Dead TEDs and plus 4 keyboard
The PLA is a fragile chip, too. Maybe this has been blown on one ore more of the faulty machines?
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Posted By
MIK
on 2013-02-15
04:54:20
| Re: Dead TEDs and plus 4 keyboard
Indeed as crock was saying, if all you have is a black screen then your TED's could be fine.
A black screen would be linked to the CPU as this is used for the video display.
The CPU will be one of these:
http://plus4world.powweb.com/hardware/MOS_75018501
As for C16's these are the most reliable of all the 264 series so if your putting your TED's back into the C16's and they don't work you must have one bad motherboard on one of your Plus/4's. Every time I have put working chips inside dead machines the chips do not become damaged if it does not work properly after that...
What do you see on the screen? Maybe you have a memory issue? In some cases TED can still function when slightly damaged and the machine will still boot up like normal, until you start to use it.
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Posted By
DeadTED
on 2013-02-17
10:19:48
| Re: Dead TEDs and plus 4 keyboard
Ok here is the latest, turns out one machine had a dead TED, one had a dead PLA, and one had a ram problem, I had replaced the 4164 chips in thi machine with 41256 chips and it worked fine as a 64k machine. For over 10 years, then recently it started acting up. So I replaced the 41256 chips with 4164 chips again and problem solved. In the end out of three plus 4 machines I managed to salvage 2, so an ok ending to an otherwise disastrous beginning.
I just wish someone could create a plus 4 on a chip like the commodore dtv, we could then slot this little board inside the plus 4 case, wire it into the keyboard, along with an sd card reader and voila!
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Posted By
Hans
on 2013-02-17
12:39:16
| Re: Dead TEDs and plus 4 keyboard
Dead Ted said:
I just wish someone could create a plus 4 on a chip like the commodore dtv, we could then slot this little board inside the plus 4 case, wire it into the keyboard, along with an sd card reader and voila!
Would be nice, but it's very unlikely that somebody will sit down and do that work.
Generally spoken, one of the 264 series main problem is the heat generated by the chips and the poor heat exhaust.
It's not a big problem (and does cost only a few pennies/cents) to protect the sensitive chips CPU / TED / PLA with heat sinks. Unfortunately, there's not enough space inside the clad to put a blower into it.
A further problem source -heatwise- is the cheap, old fashioned 7805 voltage regulator with its ceramic resistor. This one generates an enormous surface temperature which often affects the neighbouring ICs. - Maybe that switch controllers resp. regulators haven't been invented when the 264 machines were built - it's, however, more likely that such chips were already available but Commodore decided to go the "cheap" way...
Nowadays, it's quite simple to replace the dangerous 7805 against a switch regulator and to get rid of the accompanying resistor at all. A typical regulator is the DC/DC converter TSR 1-2450. Price in Germany between € 8 and € 12, depending on the supplier. Should be available almost everywhere.
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Posted By
MIK
on 2013-02-17
13:22:45
| Re: Dead TEDs and plus 4 keyboard
Glad to hear you got two Plus/4's back up and running out of what you had left. Yeah not always doom and gloom as it's normally the chips first and one faulty chip won't really effect the others so you can keep swapping them hoping a spark of life comes back in to one. 
Better luck with your new builds of +4's!
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Posted By
Litwr
on 2013-02-18
05:04:33
| Re: Dead TEDs and plus 4 keyboard
http://www.youtube.com/watch?v=QnHFO0NRtWs
http://www.youtube.com/watch?v=m0ZHmZkv3CU
http://www.youtube.com/watch?v=2LM2bom8fsw
So Plus4emu with RaspberryPi will make the trick.
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Posted By
DeadTED
on 2013-02-18
16:25:57
| Re: Dead TEDs and plus 4 keyboard
The ingenuity of people never ceases to amaze me! Only one catch I don't get a userport on the pi as that is why I mainly use the plus4. I have built many hardware control interfaces which rely on the userport. But still would be nice to preserve a plus 4 in this manner, if someone could figure out how to interface the keyboard.
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Posted By
Litwr
on 2013-02-19
10:21:41
| Re: Dead TEDs and plus 4 keyboard
http://www.vesalia.de/e_keyrah.htm - it is about keyboard of retro-computers.
IMHO the user port has very easy electronics. So it may be easy reproduced and connected with proper easy interface to USB. The only problem is the emulator's support. VICE and Plus4emu has open source code so it is not too difficult to add a subroutine or to ask the developers.
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Posted By
DeadTED
on 2013-02-19
18:59:57
| Re: Dead TEDs and plus 4 keyboard
Damn, you have me all worked up now to make this happen, however, seeing that I work 12 hours a day, it would be great if someone can make it happen for me and I just pay them ! Any takers? That is for an emulated plus 4 with user port support, actually all I need is 8 io ports accessible via plus 4 basic and machine language, ADC support would be a huge bonus!
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Posted By
Overdoc
on 2013-02-20
13:36:09
| Re: Dead TEDs and plus 4 keyboard
About the dead PLA:
I think it shoud be posssible to replace the PLA with an Eprom. At lest one the C64 tis works fine, but requires Eproms with correct timing.
There is also one available from Individual Computers based on a FPGA, called Super-PLA, which I think can also be configured for a PLus/4 ?!
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Posted By
crock
on 2013-02-20
17:18:40
| Re: Dead TEDs and plus 4 keyboard
There is also one available from Individual Computers based on a FPGA, called Super-PLA, which I think can also be configured for a PLus/4 ?!
That's right, and they work well. Jens recently updated the design to rectify a bug in the logic of the first super-PLA.
[edit]...and I have a couple of spare PLA's as well. PM me if you're interested.
Rob
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Posted By
DeadTED
on 2013-02-21
22:50:09
| Re: Dead TEDs and plus 4 keyboard
Damn shame, anyway we can encourage these guys to work together and get this baby going again?
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Posted By
Litwr
on 2013-03-01
08:06:59
| Re: Dead TEDs and plus 4 keyboard
I've just checked Raspberry Pi documentation. It has GPIO which consists of 8 bit bidirectional i/o port and a serial port. So the main problem will be only the proper connector and a small piece of code for the emulator. There are several minor problems. GPIO uses 3.3V logic but it should (?) be compatible with 5V. GPIO may handle only up to 0.016A current. These problems look simple for the electronic solution.
BTW It looks like this Raspberry with proper software (ported from C1541EMU or 1541u) and easy cable may make obsolete all other solutions. It may give 100% 1541 compatibility plus a lot of functions realized by power of RISC CPU and 512 MB RAM.
IMHO I can even think that 700-1000MHz CPU can emulate all +4 chips electronics and produce via proper port with several dozen wires all signals of TED, CPU, RAM (any size will be available!), ... 
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Posted By
DeadTED
on 2013-03-03
08:11:03
| Re: Dead TEDs and plus 4 keyboard
Seriously this is just a tease! BTW I do not mind what voltages or current is produced by the IO port as I can alter my devices, as long as it can be programmed in the exact same way as +4 basic or machine code...
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