I have questions about this article:
VGA video generator and moving objects with PS2 keyboard:
https://olimex.wordpress.com/2016/07/13/fpga-tutorial-vga-video-generation-with-ice40hx1k-evb-ice40-io-in-verilog/
Can you connect a PS/2 mouse to the PS/2 connector of Olimex iCE40-IO IO-modul VGA/PS2/IRDA? If you use Y-splitter cable for PS/2, can you connect both a keyboard & a mouse at the same time? Otherwise I think you should develop a new version of the board that can use a Y-split cable.
Can you use this example also with Olimex iCE40HX8K-EVB? Are there any changes in that case? Is an open source tool-chain also available for iCE40HX8K-EVB?
QuoteCan you use this example also with Olimex iCE40HX8K-EVB? Are there any changes in that case? Is an open source tool-chain also available for iCE40HX8K-EVB?
Yes, you can use it. If there are changes needed, they would be minimal, but I assume there are none. The same tool-chain will work for both iCE40HX?K-EVBs. Links are on the product pages.
QuoteCan you connect a PS/2 mouse to the PS/2 connector of Olimex iCE40-IO IO-modul VGA/PS2/IRDA? If you use Y-splitter cable for PS/2, can you connect both a keyboard & a mouse at the same time? Otherwise I think you should develop a new version of the board that can use a Y-split cable.
The PS/2 connector just connects the input device to the FPGA. What happens with then has to be programmed in the FPGA. https://github.com/OLIMEX/iCE40HX1K-EVB/blob/master/demo/ice40-io-video/example_7.v (https://github.com/OLIMEX/iCE40HX1K-EVB/blob/master/demo/ice40-io-video/example_7.v) shows how to use signals from a keyboard. You could just as well program correct responses to mouse movements. There's an example at opencores.org: https://opencores.org/websvn,filedetails?repname=ps2&path=%2Fps2%2Fweb_uploads%2Fps2_mouse.v (https://opencores.org/websvn,filedetails?repname=ps2&path=%2Fps2%2Fweb_uploads%2Fps2_mouse.v). Once you have both working, you can study how the splitter multiplexes the signals, and handle that on the FPGA too.
Good luck with your project!
I've looked at the schematics now and you can't connect a PS/2 Y-splitter cable (https://www.amazon.com/StarTech-Keyboard-Splitter-Adapter-KYC1MF/dp/B000067SLZ) since pin 2 and 6 are not connected. :(
https://github.com/OLIMEX/iCE40-IO/raw/master/ICE40-IO_Rev_A.pdf
https://en.wikipedia.org/wiki/PS/2_port
Pin 2: Sometimes, keyboard Data for splitter cable.
Pin 6: Sometimes, keyboard Clock for splitter cable.
The mouse/keyboard splitter does not multiplex signals, but uses unused pins, and old laptops support this.