I successfully repaired my 464 and 6128 that were not starting up to the ready prompt today. 8)
However....
The 6128 boots to the prompt and I get characters immediately fill the prompt with no keyboard attached, its just the bare board with power.
ic101 aka 74ls145 need replacing?
Nope, if the keyboard isn't attached the phantom keys can only be coming from the AY or the 8255. The 74LS145 "feeds" the keyboard scanning, the AY and 8255 send the results to the CPU.
Bryce.
98]piytwq means that bit 3 of the keyboard row is stuck low.
As Bryce said, you best bet are the AY first then the 8255
Have you been playing with the bootup distributor name message ? :D
Cheers,
Shane
Ok got up early to play :D
Put the MB back in the case and hooked kb, speaker back up.
When the character buffer fills up the speaker kicks in with a mechanical/raspy sounding stutter, not a high pitch musical tone like you get normally.
If you press the Enter key you get a new line and everything is fine. You can enter commands and everything works.
The keyboard's only problem is that q,w and t do not work.
I swapped the keyboard for a working one and it does the same so its a mb chip problem I assume.
I tested every key.
Very frustrating 'cause I cannot type "cat" to see if the floppy works. Unless someone can tell me how to input ascii codes like in MSDOS land.
The machine works as it should, problem gone till you boot up again.
This machine's 6845 chip had to be replaced.
To me it sounds like the AY sound chip is gone (no pun intended).
No the ISP brand is the way it was when I got it and is it's original LK setting.
ISP = Orion = OEM in Korea.
Here in OZ we normally got the AWA or Amstrad brand.
Maybe it was a "grey" market import.
Quote from: Bignumbas on 23:36, 22 May 17
The keyboard's only problem is that q,w and t do not work.
I swapped the keyboard for a working one and it does the same so its a mb chip problem I assume.
Very frustrating 'cause I cannot type "cat" to see if the floppy works. Unless someone can tell me how to input ascii codes like in MSDOS land.
No the ISP brand is the way it was when I got it and is it's original LK setting.
ISP = Orion = OEM in Korea.
Here in OZ we normally got the AWA or Amstrad brand.
Maybe it was a "grey" market import.
1)You can try this...
? "ca"+chr$(116)
This will print 'cat'...then you can copy it and enter it...probably could be done a neater way, but this would work.
2)Interesting...maybe somebody previously played with the links.
Pretty sure ISP was never officially used...or one has never come up that I have ever seen.
Only 'Amstrad', 'Schneider', Awa', and I beleive 'Solavox' may have crept in...
http://www.cpcwiki.eu/index.php/LK-selectable_Brand_Names (http://www.cpcwiki.eu/index.php/LK-selectable_Brand_Names)
Cheers,
Shane
Well that input works, I get "cat" then the ready prompt but no response from the drive.
I swapped it for a working one and still the same, no action at all, no spin up or head movement.
Looks like that's on the list too, maybe a new disc controller chip.
Thanks for that.
Quote from: Bignumbas on 00:28, 23 May 17
Well that input works, I get "cat" then the ready prompt but no response from the drive.
I swapped it for a working one and still the same, no action at all, no spin up or head movement.
Looks like that's on the list too, maybe a new disc controller chip.
Thanks for that.
Just to confirm...my dodgy off the top of my head method with simply print the characters 'cat' but not execute it in the same way typing and entering it does.
So once you have cat 'printed' on the screen, copy it using the 'shift' + cursor keys, then copy key.
Entering that should then execute the command.
You would think you will at least get a 'disc missing' error at the least.
UPDATE:
Actually, a much simpler thing would be to to reset the computer to the boot message and then simply type 'ca' then copy the 't' from one of many points in the boot message.
or
Set function key 0...
key 0,"ca"+chr$(116)
This sets f0 to 'cat' until you reset the computer.
Chears,
Shane
OK, I was trying to remember how to copy the command line, its been too long. I last owned a CPC back about 1989.
In the meantime I find the drive is not dropping the disk onto the head.
Really weird I cannot see why it would not and about every 100 inserts it works?????
Its a model eme-155.
The 464 says it is An AWA.
The LK1 and LK2 definitely look like original soldering to me.
Quote from: Bignumbas on 04:12, 23 May 17
OK, I was trying to remember how to copy the command line, its been too long. I last owned a CPC back about 1989.
In the meantime I find the drive is not dropping the disk onto the head.
Really weird I cannot see why it would not and about every 100 inserts it works? ??? ?
Its a model eme-155.
The metal frame that holds the disk has sliders on either side is sticking, these need to be greased.
Bryce.
I did that, poked the stuff in with a pointy thing around the brass and slots after I wd40'd the cradle
The only way I can get it to go down it to disengage the lever/catch thing on the right at the back as you look at the front.
What am i missing here, it looks such a simple thing. :-\
The black plastic hook is usually the bit that sticks. Make sure it can move far enough to engage.
Bryce.
It's a stainless steel hook.
I have also gone for the slow boat from China again and ordered the ay chip to maybe fix the phantom key thing.
Yup, just realised it's the 155 you are talking about which doesn't have the plastic hook. On the 155 you need to make sure the following areas are smooth and well greased.
Bryce.
Yep, have put it to oneside for the moment.
Its a really weird mechanical problem.
It actually works every 50 tries.
I think I need another one to compare it to side by side.
The new Ay chip fixed the keyboard problem too.