Hi

I have been using the Mach XO3 for a few things, but the issue is usually that its in a BGA-256 which is not so easy to handle and replacing it is hard once its been soldered to the board.
For that reason I am considering making a DIP package with the MachXO3, flash, FTDI2232, USB plug and some memory on it. Either as a DIP40 or DIP64.

I was thinking of using jlcpcb and their assembly service. I would need to use the 3.3V version with 9400 cells. I am leaning towards 1 or 16MByte SRAM.

Would this be a product that anyone else (here) would be interested in?

Do you already have a breakout strategy that is compatible with JLCPCB manufacturing guidelines?

I have used jlcpcb to make one of my cards with the MachXO3 in the past. It had 4 layers and manual routing to get to about 85% of the connections. Those cards worked fine. I may test 6 layers, but I don’t think its strickly necessary for the BGA itself…but that doesn’t mean its a bad idea..

With a DIP40 it would be interesting to make the power lines 6502 and 6522 compatible (and maybe some other 65xx). I haven’t thought too hard about it yet since I am on holiday without my pc…

Once I get home I will try some preliminary routing with one SRAM to see how it maps out. If there is some way to get the pins on one side without holes all the way through, that may be beneficial for the size. Edit: Surface-hold pins was what I had in mind..

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

JLCPCB doesn't support blind vias, but PCBWAY does. They are more expensive though. I just ordered 10 small boards with blind, filled microvia in pad, and it was about $500 total. That was for a BGA 176 with 0.65 mm pitch.

Right now JLCPCB has no MACH (XO2 or XO3) parts available, and I'm afraid it's going to be like that for a while. The BGA packages are ideal, since you can have standard through hole headers.

I'm not so sure how the SMT headers will handle the stress of being inserted and removed from sockets several times.

I have looked into the routing and in order to get everything on a 6502-sized PCB, I will need a smaller SRAM than what I used before. Luckily, its available in BGA so then its just about routing. I probably need to do some serious manual work to get it done, but its not impossible. As for MachXO3, they are available in october, but I will need to buy like 100pcs… Still, its not that bad if the interest is there. I do have a few already (from an earlier project) which is good enough for a couple of test rounds.

If the device is made, I think it can be done to a cost of around $50 without USB and around $60 with USB. The one without USB will require a JTAG programmer.

Trying follow up on this.

There is no way I can place the MachXO3 at 14x14mm without blind vias. You can get smaller packages, but I have to keep those BGA balls at 0,8mm spacing in order to hand solder them (with stencil and paste)... even that is pushing it... So the DIP pins can't penetrate the board. On the positive side, using BGA256 will also enable this to be used with the new MachXO5 which has 25K logic cells.

PCBWay seems to give a decent price on blind vias... if I order 100pcs that is. Almost same price for 10pcs.. but at 100pcs I can get them at $4.11/pc... Kind of expensive if I get bugs... which I will... so for prototypes one needs to cheat. That is to make two independent PCBs and simply solder them together.

As for programming, I think the FTDI 2232 chip and USB can be on a separate PCB. I want to keep the PCB close to the 2.08x0.6 inch of the 6502 DIP40, and its easier if you just plug the other pcb into it when you want to reprogram.

I'm interested in FPGA which can be programmed via an open source, command line utility. However, I am not interested in any BGA chips. If you plan something for a chip with less pins, especially if it is pre-soldered, I am very interested.

_________________
Modules | Processors | Boards | Boxes | Beep, Beep! I'm a sheep!