Snap - just done the same. - bench power supply drawing 460ma - components all cool to touch.Forgottenmyname wrote: Fri Sep 14, 2018 10:15 pm Ok so a brief update.
I've plugged the board into my bench power supply, just the two five volt and two 0 volt rails and recorded a current use of 440ma.
None of the components are even warm to touch after being on for 5 mins but no video as yet.
PCB Build - Progress - Post your Pics here :-)
Re: PCB Build - Progress - Post your Pics here :-)
Re: PCB Build - Progress - Post your Pics here :-)
Ok, so far:
Reset circuit toggles cpu ok.
_Halt is high, so the cpu is running.
8mhz to you is stable.
16 and 32mhz at shifter seem good to me.
_AS at cpu has a square 1mhz signal and the datalines seem to all have the same 1mhz triangular signal.
MMU seems to be communicating ok with data on the MAD lines.
I'm willing to bet either I've miss soldered something on the rgb circuit or something is missing, as nothing really happening on the monitor plug.
Will dig out my old CRT tv tomorrow and see what that does.
Reset circuit toggles cpu ok.
_Halt is high, so the cpu is running.
8mhz to you is stable.
16 and 32mhz at shifter seem good to me.
_AS at cpu has a square 1mhz signal and the datalines seem to all have the same 1mhz triangular signal.
MMU seems to be communicating ok with data on the MAD lines.
I'm willing to bet either I've miss soldered something on the rgb circuit or something is missing, as nothing really happening on the monitor plug.
Will dig out my old CRT tv tomorrow and see what that does.
If it ain't broke, test it to Destruction.
Re: PCB Build - Progress - Post your Pics here :-)
Cool, we can't be far off with similar figures.Icky wrote: Sat Sep 15, 2018 9:46 pm
Snap - just done the same. - bench power supply drawing 460ma - components all cool to touch.
Did you have no video either Icky?
If it ain't broke, test it to Destruction.
- alienkidmj12
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Re: PCB Build - Progress - Post your Pics here :-)
this all sounds awesome, well done guys, been a bit busy but had a good read tonight 
Re: PCB Build - Progress - Post your Pics here :-)
Hi - No video yet. The monitor did sense something at one point i.e. no-signal to a flicker, but I'm putting that down to just background noise as I have not seen it since.Forgottenmyname wrote: Sat Sep 15, 2018 9:58 pm Cool, we can't be far off with similar figures.
Did you have no video either Icky?
Like you I will start looking tomorrow more closely with my scope
Re: PCB Build - Progress - Post your Pics here :-)
And now I have life but no meaning
Not sure what I have here but I have output.
- BlankVector
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Re: PCB Build - Progress - Post your Pics here :-)
Exciting progress 
Subscribe to my Vretrocomputing channel on YouTube and Facebook. Latest video: Display a color pixel in assembly language on Atari ST.
- alienkidmj12
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- Joined: Tue Aug 22, 2017 1:39 pm
Re: PCB Build - Progress - Post your Pics here :-)
i can see trees and sunset there, in the distance !! or you could actually say, waves washing up on the shoreline
Re: PCB Build - Progress - Post your Pics here :-)
Does the floppy drive get accessed ?
Looks like a sync issue so far.. Even without tos running the video should be stable.. Its worth checking back from the monitor port to glue etc.. Don't assume I've wired the connector up right either
Looks like a sync issue so far.. Even without tos running the video should be stable.. Its worth checking back from the monitor port to glue etc.. Don't assume I've wired the connector up right either
Re: PCB Build - Progress - Post your Pics here :-)
I don't have the floppy connected at the moment.exxos wrote: Sun Sep 16, 2018 12:11 am Does the floppy drive get accessed ?
Looks like a sync issue so far.. Even without tos running the video should be stable.. Its worth checking back from the monitor port to glue etc.. Don't assume I've wired the connector up right either![]()
But here is video of first boot. As you can see I get the black screen then it starts to go out of sync.

