Here is an example of another nice layout package. PLCC packages were heavily common before BGAs, etc, for very reliable high pin count IC packages. These FPGA modules utilize the PLCC68 package form factor which allows several mounting options and socket options in SMT and TH. Would also allow use as a castellated module.
I think I want is a Prop II and minimal associated circuitry to get it running on a board like this: http://www.acmesystems.it/aria
Preferably without eating any pins wasted on an SDRAM that we don't need.
These FPGA modules utilize the PLCC68 package form factor which allows several mounting options and socket options in SMT and TH. Would also allow use as a castellated module.
Wow, now that is clever, I've seen & mentioned the simpler routed.sliced holes in many designs, but this plates-after-route1, then does a post-plate route. - so the added cost will be small & PCB thickness may need to be carefully selected, but there are no brick walls to doing this.
That can direct mount just as easily as the simpler edge details, but has the benefit it can also fit into a socket.
I think you can still get gold plated PLCC sockets.
Edit: yes, Mouser show PLCC68 151-1569 and PLCC84 151-1585 in stock in Gold. & Digikey have them too.
Removal could be tricky, looks like they actually try to prevent the common removal tool, which is likely to damage the PCB corners.
Thru hole Sockets do have 4 holes, and standoffs, so those holes could be left open for a Push removal tool ?
The module pictured at the link at the end has a component layout that resembles the proposed layout of the Prop 2 module. Upon clicking the pic, four large close-up views are available (by repeatedly clicking), including one showing the module mounted to a carrier board. It's another castellated design. Although it doesn't permit ready insertion into a standard socket (as above), it allows for an easy-to-solder, low-profile mount with a carrier board. But I wonder if a module with this kind of edge connections is relatively expensive to manufacture. Link: http://www.ghielectronics.com/catalog/product/373
I really love Chip's module. At the same time, I see advantages to Andrew, Rayman and Jret's ideas.
For instance, I can imagine a series of Chip's modules all plugged into a backplane, all with adequate memory and processing power to handle a vigorous stream of image data flowing
down a pipeline to them (or other large data related task, which can be similarly partitioned). But then... with Chip's module, in a backplaned multi-prop2 system what is to be done about common components that need to be added to each module? Do they sit on the backplane between the modules?
With the other approaches, you would have to add a carrier board to plug it into a back plane... but then you
have the opportunity of differentiating among the modules... each could also be given unique resources and tasks.
With ethernet... is the idea of a backplane really the right idea?
I think what I would do is ... keep Chip's idea, but add an identical connector on both ends!!!
I really don't know (of course)... But I do know is that when the second crate comes off that very slow boat from you know where... I want a bunch of those modules and I will be very happy with whatever board arrives first;)
Another retro computing thing with BASIC and "Glory Days" appeal ....
We just sit around talking about the old times,
she says when she feels like crying
she starts laughing thinking about ...
Glory days well they'll pass you by
Glory days in the wink of a young girl's eye
Glory days, glory days....
Only my "glory days", as a Brit, were filled with other things. The "Wendy" song made an impression at some point. After that came the "bored in the USA song"...
Ok, 6 attempts as posting something to add to this conversation, and all I can come up with is there are good and bad sides to each and every design offered. This being said, if not for the professional development boards I've purchased, I would not have done nearly as many projects as I have, simply because of the hardware requirements needed to "test" or "play" with an idea or two.
While the simpler Demo boards and BOE's offer hardware and everything you need to do, the simple fact that a single board with most everything needed to develop with is contained really helped me grow with the hobby.
Comments
http://www.hdl.co.jp/en/index.php/products/plcc68-series.html
Preferably without eating any pins wasted on an SDRAM that we don't need.
If I had any of those Euro things
Wow, now that is clever, I've seen & mentioned the simpler routed.sliced holes in many designs, but this plates-after-route1, then does a post-plate route. - so the added cost will be small & PCB thickness may need to be carefully selected, but there are no brick walls to doing this.
Zoomed detail is here
http://www.hdl.co.jp/PLCC/img/PLCC68img2.jpg
That can direct mount just as easily as the simpler edge details, but has the benefit it can also fit into a socket.
I think you can still get gold plated PLCC sockets.
Edit: yes, Mouser show PLCC68 151-1569 and PLCC84 151-1585 in stock in Gold. & Digikey have them too.
Removal could be tricky, looks like they actually try to prevent the common removal tool, which is likely to damage the PCB corners.
Thru hole Sockets do have 4 holes, and standoffs, so those holes could be left open for a Push removal tool ?
For instance, I can imagine a series of Chip's modules all plugged into a backplane, all with adequate memory and processing power to handle a vigorous stream of image data flowing
down a pipeline to them (or other large data related task, which can be similarly partitioned). But then... with Chip's module, in a backplaned multi-prop2 system what is to be done about common components that need to be added to each module? Do they sit on the backplane between the modules?
With the other approaches, you would have to add a carrier board to plug it into a back plane... but then you
have the opportunity of differentiating among the modules... each could also be given unique resources and tasks.
With ethernet... is the idea of a backplane really the right idea?
I think what I would do is ... keep Chip's idea, but add an identical connector on both ends!!!
I really don't know (of course)... But I do know is that when the second crate comes off that very slow boat from you know where... I want a bunch of those modules and I will be very happy with whatever board arrives first;)
Rich
http://dimitech.com/
Not sure I'm so happy about that big ugly socket thing.
Sometimes I wish it was.
All I want is a Prop II on a board where I can use all free I/Os at will.
P.S. Who is this Bruce Spingsteen of which you speak?
A USA Singer-Songwriter-Musician I listened to in my own glory days ....
Only my "glory days", as a Brit, were filled with other things. The "Wendy" song made an impression at some point. After that came the "bored in the USA song"...
<homer simpson>Doh!</homer simpson>
The Association WIndy? That melody still rots my brain.
Is there any update on the pcb???
Pinouts???
Dimensions???
While the simpler Demo boards and BOE's offer hardware and everything you need to do, the simple fact that a single board with most everything needed to develop with is contained really helped me grow with the hobby.