Have you looked at porting it to the QMTECH Xilinx Zynq7000 Bajie Board? Just a $60 board that is in stock and also has more breathing room. Also includes hard ARM cores as part of the SoC, so you likely wouldn't need to allocate a RISC-V core in the PL. No need to design a new board, and still a cheap and readily available board then.
That board has been sitting in my shopping cart for over half a year now, and I never get around to buying it, because I suspect I won't be able to use it. My problem with the full SoC boards is that the memory can, typically, go either to the CPU or the FPGA, but not easily both. Since the focus of this project is the FPGA, this means I'd be wasting funds on a CPU I'll end up not being able to use. You can see it really well with the MiSTer, where despite having memory on board, if you want your 8-bit device to have memory you need to buy it an SRAM module. Those are _expensive_. In the end, cost is a huge factor here. The reason those boards cost $60 is because they were produced before the supply chain collapse and the stock never ran out (a red flag in and on itself). If you check the cost of just the SoC chip on mouser, the cheapest one go for over $130. This means the project will not reach the price point I want for it. At those prices, you might as well go get a MiSTer and receive a more mature product.
@@CompuSAR Cheers, that makes sense. How about the Basys3? It's quite a bit more costly at $160, but they're readily available in good stock. They include a USB HID controller which emulates a PS/2 bus to the FPGA too. It also has the advantage of being the primary hardware target of the very nice hneemann's "Digital" logic simulator, so they're a good FPGA to buy for people generally interested in learning hardware architecture. They include a VGA port, though you could also drive HDMI over PMOD with something like the adapter 1BitSquared offers.
Another very nice FPGA board that's available in quantity is the ULX3S. This is probably the nicest board available that is well supported by the open source yosys toolchain, and there are many well documented examples targeting the board. The problem here for you might be that it is a Lattice ECP5 FPGA, so would be a more involved port and wouldn't work with your current Vivado setup. It is also costly, in the ballpark of $150. Though I suspect that the $60 Colorlight i9-v7.2 board which uses the same FPGA could be an option, and is also available in quantity.
@@australai It seems to me you might be missing important context. If you can spare the 8 minutes it takes, I explained the project's goals in the video at ua-cam.com/video/s1zQQAN6jmU/v-deo.html.
@@CompuSAR Thanks, I've seen it. Worth noting that now the DE10-Nano has increased in price to $230 and is not in stock. The price of a MiSTer kit has risen from ~$370 to more than $500. So, a $150 board that is actually in stock would still be a nice option. The Colorlight i9-v7.2 with lots of stock on Aliexpress for $60 is super barebones and has lots of PMOD IO. FWIW, I just had a look through the reference manual of those Zynq 7000 FPGAs, and it seems the DDR3 is connected to both the PS and the PL via a high-speed fabric, though I think you're right in suspecting that the stock is limited, and those boards will all be gone soon.
What an interesting and highly educational project. Nice work!
Thank you. It is much appreciated.
Have you looked at porting it to the QMTECH Xilinx Zynq7000 Bajie Board? Just a $60 board that is in stock and also has more breathing room. Also includes hard ARM cores as part of the SoC, so you likely wouldn't need to allocate a RISC-V core in the PL. No need to design a new board, and still a cheap and readily available board then.
That board has been sitting in my shopping cart for over half a year now, and I never get around to buying it, because I suspect I won't be able to use it.
My problem with the full SoC boards is that the memory can, typically, go either to the CPU or the FPGA, but not easily both. Since the focus of this project is the FPGA, this means I'd be wasting funds on a CPU I'll end up not being able to use. You can see it really well with the MiSTer, where despite having memory on board, if you want your 8-bit device to have memory you need to buy it an SRAM module. Those are _expensive_.
In the end, cost is a huge factor here. The reason those boards cost $60 is because they were produced before the supply chain collapse and the stock never ran out (a red flag in and on itself). If you check the cost of just the SoC chip on mouser, the cheapest one go for over $130. This means the project will not reach the price point I want for it. At those prices, you might as well go get a MiSTer and receive a more mature product.
@@CompuSAR Cheers, that makes sense. How about the Basys3? It's quite a bit more costly at $160, but they're readily available in good stock. They include a USB HID controller which emulates a PS/2 bus to the FPGA too. It also has the advantage of being the primary hardware target of the very nice hneemann's "Digital" logic simulator, so they're a good FPGA to buy for people generally interested in learning hardware architecture. They include a VGA port, though you could also drive HDMI over PMOD with something like the adapter 1BitSquared offers.
Another very nice FPGA board that's available in quantity is the ULX3S. This is probably the nicest board available that is well supported by the open source yosys toolchain, and there are many well documented examples targeting the board. The problem here for you might be that it is a Lattice ECP5 FPGA, so would be a more involved port and wouldn't work with your current Vivado setup. It is also costly, in the ballpark of $150. Though I suspect that the $60 Colorlight i9-v7.2 board which uses the same FPGA could be an option, and is also available in quantity.
@@australai It seems to me you might be missing important context. If you can spare the 8 minutes it takes, I explained the project's goals in the video at ua-cam.com/video/s1zQQAN6jmU/v-deo.html.
@@CompuSAR Thanks, I've seen it. Worth noting that now the DE10-Nano has increased in price to $230 and is not in stock. The price of a MiSTer kit has risen from ~$370 to more than $500. So, a $150 board that is actually in stock would still be a nice option. The Colorlight i9-v7.2 with lots of stock on Aliexpress for $60 is super barebones and has lots of PMOD IO. FWIW, I just had a look through the reference manual of those Zynq 7000 FPGAs, and it seems the DDR3 is connected to both the PS and the PL via a high-speed fabric, though I think you're right in suspecting that the stock is limited, and those boards will all be gone soon.