Sorgelig wrote:It's not hard to use UART connection. MiSTer framework provides standard UART signals to connect to supported core. So, need some one who knows how to connect C64 side to UART and knows the required software.
You don't need a UART. You just need to add 3 lines from the CIA to FPGA pins:
Tx = USER PORT 'M' (pin 23), connected to CIA U2 pin 4 (PA2).
Rx = USER PORT 'B' (pin 14), connected to CIA U2 pin 24 (/FLAG2).
Rx = USER PORT 'C' (pin 15), connected to CIA U2 pin 10 (PB0).
Tx -> Tx port pin USB-C connector
The two 'RX' connections are tied together -> Rx port pin (USB-C connector)
If this was supported in the core, then you could use any modern modem through the USB-C connector.
One thing that the C64 emulation does need is the removal of the copyrighted ROM code (computer and disk drive) and make it load an external ROM files like the arcade cores do.