(A500+) Ctrl + Amiga + Amiga does not work.

[sim085]

Hi,

As I said in the introduction section I just connected my A500+ and everything seems to have worked fine. I have also inserted some floppy-disks and these loaded without any problems. However I found out that the Ctrl + Amiga + Amiga (reset) don’t want to work! Both Amiga buttons work fine when tested independently, but I do not know how I can test if the Ctrl button is working (although I do not see any reason why this button should not work since all the other buttons on the keyboard work fine as well).

Additionally; My A500+ still has the clock battery on it. I already called my cousin so that he can get all the required tools to pull this battery out and then I will try to clean any damaged area. I have found a very good guide how to do this on this forum. However is it possible that the Ctrl + Amiga + Amiga (reset) function was killed because of this? I am not sure about this since the keyboard seems to be on a different board then the motherboard.

Any comments on what the problem could be are more than welcome

Regards,
Sim085    

[Protek]

Have you a possibility to try another keyboard? I've got the same problem with one A500 keyboard but Ctrl-A-A works with a spare one. Too bad that this one misses the Backspace key and it needs more than a cap. I wonder if it would help to swap the circuit boards between the keyboards or do I have to dismantle the whole thing to get the backspace button base?

[sim085]

At the moment I do not have another keyboard to try out however I saw some on sale at eBay. However before buying a new keyboard is it possible to test the Ctrl button on its own? Unfortunately I do not remember the use of this key on the A500+ (apart to restart the computer). If the Ctrl does work fine then could it be something else on the keyboard?

Regards,
Sim085

[Protek]

If I remember correctly, you have a possibility to test the keys with some of the utils that come with the OS.

[orange]

you could test them with that old setkey program (IIRC)

check the plastic beneath the keyboard PCB, the pins might have pierced it and shorted with RF shielding.

[sim085]

Does this setkey program come with workbench? I think I no longer have any workbench disks What is the best workbench version for the A500+ and from where could I buy it? I will buy a hard drive for the A500+ soon so I do not know if that will need a different workbench.

Thanks for all the comments so far

[Rob]

If you have to screen open such as Workbench and Deluxe paint left Amiga + M should switch screen and right Amiga + X,C,V are used cut copy paste, these combinations should work in a text editor.

As for the battery you should be able to use a cell holder from a dead PC.  My brother soldered one into our A500+ and the pins line up perfectly with holes in the motherboard.

[sim085]

Hi Rob,

Unfortunately I do not have any Workbench disk However I found the original package of Digita Wordworth. I inserted the Wordworth disk and Amiga Workbench was loaded (some basic form of it at least).

When I press 'Right Alt' + 'Right Amiga' buttons I can see the top menu change and provide options. The same happens when I press the 'Right Alt' + 'Left Amiga'. This means that the Amiga buttons both work.

Also from the top menu I select the option 'Execute Command'. Here when I press any key everything enter fine. When I press 'Ctrl' + 'X' the text already entered is cleared! So I assume the Ctrl also works.

I also tried the 'Shift' button and all other button on the keyboard all seem to work fine.

So at this point I think that the Ctrl and the two Amiga buttons both work. I read somewhere that the problem could be coming from some transistor on the keyboard however not sure if this is relevant for the A500+.

I am happy the all buttons seem to work fine but feel at a loss why the Ctrl + Amiga + Amiga (Reset) is not working

I am going to change the battery tomorrow or the day after, maybe I try to put a cell holder from a dead PC as you suggested Maybe this is somehow related although I am afraid it is not

Is there anyone who is maybe running an A500+ without battery which has the same problem?

Regards,
Sim085

[davideo]

The battery on a 500+ does nothing more than keep the time while your Miggy is turned off - as far as I know.

So I wouldn't have thought that was the problem.

Dave G  8-)

[Zac67]

If Ctrl-A-A doesn't work there are three possible causes:
- one of the keys is dead (check Ctrl in a shell window: Ctrl-M is , Ctrl-I and so on)
- the line from keyboard to mainboard is dead - check with a multimeter
- the line from the keyboard connector to the rest of the board is dead - check by powering up with disconnected keyboard and short pin 3 to ground; if Amy doesn't reboot, you've found the problem

[Lockon_15]

Actually, there is a fourth reason.
- a dead transistor on keyboard PCB
There are 2 transistors, one of them is used for reset action. I had this scenario a year ago, solved with equivalent transistor (can remember, BC5xx series for sure)

[sim085]

Hi Zac67,

Thanks for your reply. The Ctrl seems to be working fine but I will test it again. I will then check the other two points when I open the A500+ to change the battery.

What is the solution for each case? Or the olution is always the same; changing the keyboard?

Regards and Thanks,
Sim085

[rkauer]

 No need to change the keyboard.

 Look for the 3rd wire (looking on the motherboard connector, left to righ), normally a red one.

 It is the reset wire.

 Using a wire jumper (with Amiga turn on), short it to the thin shield somewhere. The Amiga must reboot. If so, you have the reset transistor burned (just change it to another equivalent), but first check the wire itself (it may have a bad contact on the connector).

[Zac67]

Actually it's been ages since I've seen an A500+...

Which transistor are you referring to? Q711? That one is only required for power on reset, not for KB reset.

[rkauer]

 Checking again the keyboard circuit, the reset line/wire is connected to the pin #8 of the 74LS27 chip on the kb board.