Hi,I'm trying to use the USB OTG present on the DECA MAX10 evaluation kit to receive and transfer data from the kit to my system. In the Qsys I have added an UART(RS-232) module in order to make the transmission possible. As per the data sheet of the DECA MAX10 kit it says that the USB OTG is connected to the transceiver chip from TI for the UART purpose. So in my top level file I need to map the receiver and the transmitter port of the UART module present in the Qsys to the receiver and the transmitter port of the USB OTG(as it's connected to a transceiver chip) but it's not clear to me which pins of the USB should be mapped. Can anyone please help me with this ? Thanks, Swarnava Pramanik
The OTG port cannot be used for RS232 without lots of software support.If you just need to see printf output for debugging, add a JTAG UART to your system. The debugger can show you printf output, but the system won't run without the debugger running. I if you need an RS232 that operates independently, you use a regular UART. Get a 3.3 volt compatible Rs232 to USB adapter. In the US, they are available from Adafruit, Sparkfun, element-14, and others. You then wire it to some pins on the expansion connector, you will need TX, RX, and ground. Use the pin planner to set 3.3 volt logic, and define the pins being used. Don't forget to configure the pin wired to TX on the adapter as RX on th FPGA and the pin wired to RX on the adapter to TX on the FPGA.
Hi Galfonz,Thanks for your reply. I already have one JTAG UART in my Qsys system. Can I use that for transferring data between my system and my FPGA kit ? Can't the USB OTG be used from transferring data from the FPGA board to my system and vice-versa ? Thanks, Swarnava Pramanik
USB can be used, but it needs a lot of software that has to work perfectly before you can transfer data. Doing a physical UART with UART to USB converter is much easier. USB IP also uses much more FPGA resources than a UART if that is an issue.If you want your project to be about getting USB working, then go for it. If you have something else in mind, use a UART.
--- Quote Start --- USB can be used, but it needs a lot of software that has to work perfectly before you can transfer data. Doing a physical UART with UART to USB converter is much easier. USB IP also uses much more FPGA resources than a UART if that is an issue. If you want your project to be about getting USB working, then go for it. If you have something else in mind, use a UART. --- Quote End --- Hi Galfonz, I got a Pmod USB to UART module in order to transfer the data. I'm connecting the module to the GPIO pins present in the board. I've assigned one pin of the GPIO to Vcc which is connected to the Vcc pin of the pmod module and explicitly mapped 2nd pin of the GPIO to 0 in my code. Also in Qsys I incorporated an UART core and mapped the rxd and txd of the UART core to the other two pins of GPIO in my code which are connected to RXD and TXD pins of the pmod module respectively physically. I have not mentioned any pins explicitly for these in the pin planner. When I'm connecting the pmod module to my system it's showing USB Serial Port( COM5 ) but data transfer is not possible still. Do I need to explicitly mention the pins of the GPIO in the pin planner which are connected to RXD and TXD of the pmod module ? Thanks, Swarnava Pramanik.