Amiga 1200 not booting

[Aminator]

My amiga 1200 won't boot. I have recapped the system but that did nothing.
There doesn't seem to be visible corrosion on the motherboard.

The symptoms are as follows:
-When i turn on the machine the power led blinks 6 times and then seems to reboot.
-The hard drive and floppy drive leds are constantly on.
-When turning on the amiga, on the display, you can see either a quick flash of a green line on top of the screen or a quick flash of white or grey line on the bottom of the screen.

[zx80]

Have you opened it and inspected it visually e.g. dead leaked battery, some old blown up ELCOS etc?

[Leon Besson]

Originally Posted by Aminator

My amiga 1200 won't boot. I have recapped the system but that did nothing.
There doesn't seem to be visible corrosion on the motherboard.

The symptoms are as follows:
-When i turn on the machine the power led blinks 6 times and then seems to reboot.
-The hard drive and floppy drive leds are constantly on.
-When turning on the amiga, on the display, you can see either a quick flash of a green line on top of the screen or a quick flash of white or grey line on the bottom of the screen.

Okay Bromigo! Have you checked the ROMs have been seated correctly? They are in the right way round as well?

Green would also indicate a CPU issue. I take it you aren’t running an accelerator?

Which revision is the Mainboard? Which ROM version? Original ROMs or aftermarket ones?

[Aminator]

Originally Posted by Leon Besson

Okay Bromigo! Have you checked the ROMs have been seated correctly? They are in the right way round as well?

Green would also indicate a CPU issue. I take it you aren’t running an accelerator?

Which revision is the Mainboard? Which ROM version? Original ROMs or aftermarket ones?

Motherboard revision 1B
I have reseated the roms and tested with known working ones but it makes no difference.
And no accelerator installed.

[nikosidis]

If the light on the driver is on all the time it seams to me that you inserted the cables wrong way.
What do you have connected?
Only Floppy? If you have HDD connected, disconnect it.

[aeberbach]

Got a voltmeter? Anything less than about 4.7v on the board and things get a bit iffy. You have to check on the Amiga board rather than on the power supply because the cable and connector can also be causing losses.

[Aminator]

Originally Posted by nikosidis

If the light on the driver is on all the time it seams to me that you inserted the cables wrong way.
What do you have connected?
Only Floppy? If you have HDD connected, disconnect it.

Hard drive and floppy are connected the right way, but the leds stay on.
when I remove the drives the leds turn off.

[Aminator]

Originally Posted by aeberbach

Got a voltmeter? Anything less than about 4.7v on the board and things get a bit iffy. You have to check on the Amiga board rather than on the power supply because the cable and connector can also be causing losses.

The voltages on the motherboard are around 4,8v.

[Aminator]

Some more info:
Let's say we have the first boot of the day, at this time the amiga power led blinks 6 times then reboots and continues this cycle until i manually turn it off. But when I turn the power back on, the power led now blinks only once and doesn't seem to reboot. The display only stays in black, again with hdd led and floppy led constantly lit, if connected

[TCD]

I found this thread: http://eab.abime.net/showthread.php?t=84158
Hopefully it's useful.

[Aminator]

Originally Posted by TCD

I found this thread: http://eab.abime.net/showthread.php?t=84158
Hopefully it's useful.

I tried booting without the monitor, (assuming it should boot now if i understood correctly) but the problem remains.

[Kin Hell]

Are your ROM's correctly aligned to the right of their respective sockets?

2nd Pic down....

https://www.retro-kit.co.uk/page.cfm...-Kickstart-31/

Try another PSU?

[cpiac64]

use diagnostic roms

[Aminator]

Originally Posted by Kin Hell

Are your ROM's correctly aligned to the right of their respective sockets?

2nd Pic down....

https://www.retro-kit.co.uk/page.cfm...-Kickstart-31/

Try another PSU?

The roms are in the correct place and like said earlier in this thread, tested with known working ones. The power supply is also a working one but i tested with another one too. No difference.

[jlin_au]

Originally Posted by Aminator

The roms are in the correct place and like said earlier in this thread, tested with known working ones. The power supply is also a working one but i tested with another one too. No difference.

The ROM sockets on an A1200 are 42 pin IC sockets while the actual ROM ICs are only 40 pin. Pins 1 and 42 (at the notch end) on both ROM sockets should be empty when the two matched A1200 v3.0 or higher ROM ICs are inserted.

It would help everyone if you could upload close up pictures of the A1200 motherboard showing the following:

1. the roms in their sockets (covering up just the license ids on their labels if any)
2. the orientation of your FDD cable connections at both the motherboard and FDD sides
3. any HDD connection
4. overlapping areas of the top and bottom of the A1200 motherboard so we can see if there is anything damaged, misconnected with bodge wires, or misplaced.

From your description the A1200 was not working prior to the recap. Are the symptoms seen the same as those prior to the recap?

[Leon Besson]

Originally Posted by Aminator

Motherboard revision 1B
I have reseated the roms and tested with known working ones but it makes no difference.
And no accelerator installed.

Okay. The only thing I can think of is if all the bodged factory wiring is in place still?

https://bigbookofamigahardware.com/b...00mbr1bbig.jpg

Have a look at the link above with a picture of a 1B revision board and check you have the bodged wiring traces that Commodore fitted to this revision.

I bought a 1D1 with a broken wire trace that did something similar.

[Aminator]

Originally Posted by jlin_au

The ROM sockets on an A1200 are 42 pin IC sockets while the actual ROM ICs are only 40 pin. Pins 1 and 42 (at the notch end) on both ROM sockets should be empty when the two matched A1200 v3.0 or higher ROM ICs are inserted.

It would help everyone if you could upload close up pictures of the A1200 motherboard showing the following:

1. the roms in their sockets (covering up just the license ids on their labels if any)
2. the orientation of your FDD cable connections at both the motherboard and FDD sides
3. any HDD connection
4. overlapping areas of the top and bottom of the A1200 motherboard so we can see if there is anything damaged, misconnected with bodge wires, or misplaced.

From your description the A1200 was not working prior to the recap. Are the symptoms seen the same as those prior to the recap?

I'll upload some pictures later this week since i'll be out of town for few days.
The symptoms were the same before and after recapping.

[Kin Hell]

https://www.diagrom.com/

[Aminator]

I got the diagrom and this is what it shows:
[ Show youtube player ]

It seems to automatically scroll through the menu.

[cpiac64]

problem with connector and/or chip of keyboard