Reviving A1200 that does not boot - Page 2

tygre · 06 June 2011, 16:00

Unfortunately, the screen remains black in all the configurations that I tried so far...

tygre · 07 June 2011, 01:47

Ah, I see it: is it indeed the IC labelled "D215"?

In my Amiga, it is written on the IC:

286X
385-12

no "555" to be seen on it...?

Thanks!
Yann

rkauer · 07 June 2011, 19:16

U29

tygre · 08 June 2011, 01:27

Thanks! Found it

So, it is really a 556 (a 14-pin combining two 555)... I am going to test the input and the two outputs to see if there are indeed some pulses... Any idea of the frequencies that I should get?

Cheers!
Yann

rkauer · 08 June 2011, 04:03

No frequencies: when the Amiga is turned on, expect to see one of the outputs switching to low (or high, cannot remember).

Check the schematics to see which pin is the correct.

tygre · 08 June 2011, 05:02

Ah, so it is really in "pulse" mode... Okay, I will check and keep you posted!

Thanks!
Yann

07 June 2011, 01:47	#22
tygre Returning fan! Join Date: Jan 2011 Location: Montréal, QC, Canada Posts: 1,434	Ah, I see it: is it indeed the IC labelled "D215"? In my Amiga, it is written on the IC: 286X 385-12 no "555" to be seen on it...? Thanks! Yann Last edited by tygre; 07 June 2011 at 01:53.

08 June 2011, 01:27	#24
tygre Returning fan! Join Date: Jan 2011 Location: Montréal, QC, Canada Posts: 1,434	Thanks! Found it So, it is really a 556 (a 14-pin combining two 555)... I am going to test the input and the two outputs to see if there are indeed some pulses... Any idea of the frequencies that I should get? Cheers! Yann Last edited by tygre; 08 June 2011 at 05:02.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Reviving our dead A1200 mainboards	ancalimon	support.Hardware	4	07 December 2011 21:07
Reviving my BlizzardPPC help	ancalimon	support.Hardware	3	28 October 2011 19:10
Reviving my old A1200 :)	iridium	New to Emulation or Amiga scene	36	25 April 2010 20:55
A1200 HD - how to boot from HD	HRMeinert	support.Hardware	31	09 May 2009 04:45
Help reviving A2000 rev 6.2	gdanko	support.Hardware	2	06 August 2006 12:03

06 June 2011, 16:00	#21
tygre Returning fan! Join Date: Jan 2011 Location: Montréal, QC, Canada Posts: 1,434	Unfortunately, the screen remains black in all the configurations that I tried so far...

07 June 2011, 19:16	#23
rkauer I hate potatos and shirts Join Date: Oct 2007 Location: Sao Leopoldo / Brazil Age: 58 Posts: 3,482	U29

08 June 2011, 04:03	#25
rkauer I hate potatos and shirts Join Date: Oct 2007 Location: Sao Leopoldo / Brazil Age: 58 Posts: 3,482	No frequencies: when the Amiga is turned on, expect to see one of the outputs switching to low (or high, cannot remember). Check the schematics to see which pin is the correct.

08 June 2011, 05:02	#26
tygre Returning fan! Join Date: Jan 2011 Location: Montréal, QC, Canada Posts: 1,434	Ah, so it is really in "pulse" mode... Okay, I will check and keep you posted! Thanks! Yann

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)