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Re: ALPHA MODIFICATIONS
Posted: 27 Sep 2018 16:47
by exxos
Forgottenmyname wrote: 27 Sep 2018 16:22
If you've kept up, your board should now look a little something like this :)
*real* computing this is :thumbup:
Re: ALPHA MODIFICATIONS
Posted: 27 Sep 2018 22:50
by Icky
Forgottenmyname wrote: 27 Sep 2018 16:22
If you've kept up, your board should now look a little something like this :)
P.s. not done the 16mhz mmu fix as it was optional.
:coolpics: - Looking good.
Re: ALPHA MODIFICATIONS
Posted: 29 Sep 2018 15:17
by PaulJ
Icky, I'm putting in missing pullups on cpu. Your picture with the extra sip pullup pac shows a pullup connected to pin 10 (dtack) but nothing on pin 9 that is identified as needing a pullup. Initially I put the extra pullups in according to your picture but dtack then reads ~680 ohms which means the 1k pullup is ther and the 2.2 k is in parallel with it. Did you get the rw pullup on dtack or am I a marble short of a full deck?
Paul
Re: ALPHA MODIFICATIONS
Posted: 29 Sep 2018 17:43
by exxos
Looks ok to me...
11111111.JPG
DTACK is on RP1 (1K) so doesn't need a pull up, Icky doesn't have one on that pin, its RW.
Re: ALPHA MODIFICATIONS
Posted: 29 Sep 2018 21:32
by PaulJ
Your right, I'm one marble short. The prior picture is 90 degree different and I've been looking at it from this perspective.
Paul
Re: ALPHA MODIFICATIONS
Posted: 01 Oct 2018 08:20
by Icky
PaulJ wrote: 29 Sep 2018 21:32
Your right, I'm one marble short. The prior picture is 90 degree different and I've been looking at it from this perspective.
Paul
Hi Paul. Nice to see you working on the board.
Why not open a topic for your pics and experience in the Alpha User Builds section.
https://www.exxosforum.co.uk/forum/viewforum.php?f=64
We would like to see where you are and some photos.
Re: ALPHA MODIFICATIONS
Posted: 01 Oct 2018 15:42
by PaulJ
I'll put something up later today.
Re: ALPHA MODIFICATIONS BGACK pull-up
Posted: 02 Oct 2018 17:54
by PaulJ
Do we need another pullup on BGACK pin 12 on processor. Once SJ1 is shorted it connects the 4.7k pullup on GLUE_BGACK (pin 40)? I may just change R150 to 2.2k?
Please advise..
Re: ALPHA MODIFICATIONS
Posted: 08 Oct 2018 16:43
by troed
Is the description for RESET FIX complete? Icky has moved the leg of the resistor which is not in the description, but without it the cut tracks don't really make sense.
edit: Ah, read further down. Also the resistor connects to internal plane I guess. I'm not used to 4 layer boards ;)
Re: ALPHA MODIFICATIONS BGACK pull-up
Posted: 08 Oct 2018 16:50
by exxos
PaulJ wrote: 02 Oct 2018 17:54
Do we need another pullup on BGACK pin 12 on processor. Once SJ1 is shorted it connects the 4.7k pullup on GLUE_BGACK (pin 40)? I may just change R150 to 2.2k?
Please advise..
There is already a pull-up on it so it resistor is not needed as previously thought..