New CPC user get a CPC 6128 but having random charters in the screen

[Bryce]

Yup, if you're getting characters with a new AY or without the AY inserted, then it's most likely the 8255 that's died. Quite unusual, they very rarely die.

Bryce.

[Sebastian Blanco]

Thank you guys gonna replace it, lucky it seem cheap and easy to find and is not some custom amstrad part.
1pcs M5L8255AP 5 Encapsulation DIP 40 Programmable Peripheral Interface | eBay

[Audronic]

Thank you guys gonna replace it, lucky it seem cheap and easy to find and is not some custom amstrad part.
1pcs M5L8255AP 5 Encapsulation DIP 40 Programmable Peripheral Interface | eBay

Watch their shipping charges $4.00 ?? Plus $3.33 US . there must be others that are less costly.


Ray

[Sebastian Blanco]

OK changed the MP5L8255APIC and the keyboard madness seem to stop.
What i found now is bizarre.
If i touch the +5 cable the computer start typing stuff by itself never seen something like this, its normal?.
video=
Now i have to test the membrane and change every one of the little springs in the keyboard they are all highly oxidized and convert into rust if you press the keys. They don´t seem to be available for sell in ebay so have to ask in a spring store if they can build them for me  .

Thanks for your help guys you are amazing 

[Audronic]

Hi Sebastian Blanko
Turn the Motherboard over and have a look at the solder joints for the +5 Volt socket ?
Or Plug and unplug the +5 Volt plug about 20 times to self clean.
Food luck
Ray

[1024MAK]

@

Food luck

@Audronic - you're always on about food. You make me hungry 

Yes, from the video, as Ray (Audronic) says, check and if needed resolder the power input connector pins. Check (look) inside to confirm that the curved metal contact is clean and not damaged. Also that the centre pin is okay.

If needed spay some isopropyl alcohol (IPA) based cleaner into the connector with the computer unplugged and the power off and then as Ray says, repeatedly plug and unplug to clean the dirt off the contacts inside.

Or it could be that the cable at or near the line plug has broken conductors inside. In which case, you will need to solder a plug on beyond the damaged section (if there is enough slack), or replace the cable. But do ensure (don't just, check, test and triple check) that you have got the polarity correct.

Mark

[Audronic]

@@Audronic - you're always on about food. You make me hungry 
Mark

Thanks for the other thoughts.
Grrrr   TYPO, it could have been "Tood,Hood,Vood, etc.


Thanks    Ray