Hello, I have two 6851s and I am going to try and build a double SID module. I was going to build a SEQ so I have a lot of the parts already, but I realize that I’m missing a couple, pretty important parts. Namely 4 Stryoflex caps (470pf) and 2 Transistors (BC547). I can basically re-purpose a lot of my other parts to work as I already have some DOUT 74HCs, and I believe the SIDs are as wide as the PICs, so I can just cut up some 40-pin IC sockets to work etc. So anyway, considering last time I had to pay 60$ to ship my stuff from Mouser, I was wondering if anyone here had just those parts that they could mail to me in Canada? I can pay you for everything, but it’s just going to be cheaper if you stuff them in an envelope for me in place of having a box shipped.
Here’s a pic of the board I designed based on Wilba’s wiring. I excluded the J10 connection as I am going to just straight connect with a ribbon cable like the FM controls. The pins are way too splayed out to be worth while.
EDIT: Removed one-sided .brd file as it is updated below
I guess it’s possible, but it would require several bridges, which are just as time consuming as a direct connection underneath. And the J10 would not be completely compatible and the core would have to have one trace moved into another place. If it was a double-sided board it would be very easy and very nice, but I made it for myself, and I only have access to copper-clad boards. I wish I could have a smash board but I just don’t have the facilities.
Here’s an attached file of the board. I looked again at having a J10 connection, like maybe a SIL or something, but it is still really difficult. Basically you’d have to just do 6 jumpers to the connector, and would still have to modify the core.
I guess it’s possible, but it would require several bridges, which are just as time consuming as a direct connection underneath. And the J10 would not be completely compatible and the core would have to have one trace moved into another place. If it was a double-sided board it would be very easy and very nice, but I made it for myself, and I only have access to copper-clad boards. I wish I could have a smash board but I just don’t have the facilities.
The list of pins to connect are the following:
Pin 8 (SID A) —> Pin 24 PIC
Pin 8 (SID B) —> Pin 22 PIC
Pin 6 (SID) —> Pin 17 PIC
Pin 12 (both 74HC) —> Pin 23 PIC
Pin 11 (both 74HC) —> Pin 28 PIC
Pin 14 (74HC A) —> Pin 29 PIC
You can get double sided copper clad boards. Anybody else who is wanting to include J10 and wants to mess around could look in to adaptin the design.
Thanks for the suggestions, I’m implementing them now, and giving the board more breathing room because of it. The caps were under the SIDs out of convenience, but I did move them out from under just cause it might save someone some time when building.
I know there are dual sided boards, I just don’t have any. I might just go ahead and work on a double layer design, but people would still have to modify the core.
EDIT: Here it is, with a SIL Connector that should easily turn into a DIL J10 connector. I wish that I could make such a board. But anyhow it has most of your improvements. Now I just wish that I could make myself a double - sided one.
I’ve never really understood how to do the ground if it’s covered in a ground plane. So I make small 16 sized connections for them all, sometimes they’re cut, but still maintain continuity and connection to ground via the ground plane. So I guess before you fill it looks a little messy.
I know what you mean. Certain programs like ExpressPCB seem to just use via’s as the ground connection, which is not always ideal really. Well, maybe it is, but I don’t really have a great deal of experience with ground plane or double sided layouts just yet!
I don’t suppose you could upload a ready to print PCB layout could you?? I’d definitely like to give your single sided board a go, and i’m at work now so I have access to a laser printer
Wops, i had same problem with board and thinked, that Linux version of Eagle had some problem with rendering it, so I have been waiting for access to some Windows machine to print it…
ACtually, I believe the dual-layered version has about the same amount of bridges needed if you’re not making a double-layered board. However I guess it requires more drilling as the interconnections to the core would require holes (if using the SIL connector)
Sweet, thanks a lot for doing that! I’ll be getting my print on tomorrow I think!!!
Comparing the double and single sided layouts, I can’t see any advantage at all with the dual layer if you’re etching yourself. There are a few bridges to make, but that’s hardly the end of the world!
I’m not sure what you mean, I looked at me PDF of the image and it was the same as yours. As for those PNGs, they are just screen captures to show what the board looks like. At any rate your posting is as good.
Those are copies of the topside. But shouldn’t the topside be mirrored? I may not. Hrrmmm. Also, I did never add the holes, because I could never find the right ones
