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General Category => Technical Support - General => Topic started by: WacKEDmaN on 17:15, 17 November 22

Title: boards with 40007 and 40010 slots
Post by: WacKEDmaN on 17:15, 17 November 22
ive been working on a board that has both 40010 and 40007 slots... the 40010 was populated originally but its looking like it maybe bad...
i have some 40007 i tried to run in this board...but there was nothing.. nothing on data lines.. and looked like the 40007 wasnt even powering up...

so i had a look at the slot... it seems this board doesnt have VCC2 required for the 40007..both the VCC2 pins are at ground

from what i read these GAs are interchangable on these boards....
but is there anything else that needs to be done to get VCC2 on pin 9 and 33?
Title: Re: boards with 40007 and 40010 slots
Post by: robcfg on 19:17, 17 November 22
Don't mix them!

The pinout is different so they don't get voltage through the same pins! Putting one into the slot of the other will just fry them.

You may need to add a capacitor or a resistor in front of the unused socket in order to use it.

Bur please, double-check it first to avoid ant problem!
Title: Re: boards with 40007 and 40010 slots
Post by: WacKEDmaN on 19:38, 17 November 22
oh of course, im not trying to run both at the same time! and i realise they have different pinouts

the capacitor is populated for both slots...

the issue is the 40007 doent have power on both of its VCC2 pins...they are connected to ground instead of 5v (VCC1 is there only)
(look at 664 vs 464 schematic, i should have mentioned this is a MC0002C 464 board)
Title: Re: boards with 40007 and 40010 slots
Post by: TotO on 19:47, 17 November 22
And the 40007 require a heatsink.
Title: Re: boards with 40007 and 40010 slots
Post by: WacKEDmaN on 19:56, 17 November 22
not if its not getting power!... doesnt seem to be even warming up in the slightest!
with the 40007 there is zero activity on the data bus...

and ive checked the chip works fine in a 40007 only board
Title: Re: boards with 40007 and 40010 slots
Post by: robcfg on 20:06, 17 November 22
That's pretty strange, as both gate arrays get their voltages from the same rails.

To illustrate it, I've done some GIMP magic to show how the traces go to both gate array sockets.
Title: Re: boards with 40007 and 40010 slots
Post by: dragon on 20:06, 17 November 22
Check acme servĂ­ce  manuals I remember that there is one Schneider with double socket that speak about the two configurations.

https://acpc.me/ACME/

And tell us the motherboard model.
Title: Re: boards with 40007 and 40010 slots
Post by: WacKEDmaN on 20:18, 17 November 22
this is what im seeing on the 2 different 464 boards i have here 

original 464 board
464-vcc2.png

MC002C board (based on 664...this is from that 664 schematic and is how this board is setup)
664-vss.png

if i check pin 9 and pin 33 on the 40007 slot there is NO power...its at ground voltage...also the 2 resistors for VCC2 are nowhere to be found!
Title: Re: boards with 40007 and 40010 slots
Post by: robcfg on 20:19, 17 November 22
He mentioned that it is a MC0002 board, that's what I've used for my picture.

Point is, if the 40010 has the right voltages, the 40007 must be getting them too.

Corroded or damaged socket, maybe?
Title: Re: boards with 40007 and 40010 slots
Post by: WacKEDmaN on 20:39, 17 November 22
ooh wait... i found where R138 and R139 are.... and they are unpopulated!

well that explains why theres no power!... guess they left them out to save pennies (but why populate the capacitor for the 40007 slot!)
Title: Re: boards with 40007 and 40010 slots
Post by: WacKEDmaN on 20:54, 17 November 22
guess i need to go grab couple of 1/2W 12ohm resistors today....another 90min walk! LOL

thanks for the help peepz
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