Hi,

I recently purchased an emPower USB-Host board (6.90.00) to test, hoping that adding an LPC546 with emUSB_Host software would be a quick and easy way to add a USB HID host (and thus a USB keyboard) to my home-made computer to replace the existing PS2 one there.

I have the USB HID demo working on the USB-Host board and can read keypresses/releases via the J-Link debugger and I am now trying to get my head into the complexities of the C++ dev environment so I can tweak the USB_HID demo project. I want to be able to modify the project so that instead of (or as well as) sending the keypresses to the J-Link via the SWD interface, I can get the LPC54605 to send the keycodes out via a serial interface to an FPGA in a custom board I'm creating. I realise there are better methods of connecting the LPC to an FPGA, but I'm happy with a two-wire serial (with CTS/RTS if necessary) for the moment if I am going to stick to just a USB keyboard peripheral.

I seem to need a bit of help and/or a pointer in the right direction though, as I can't work out how to set up a simple serial interface in the LPC546. I'm brand-new to the LPC546xx and very inexperienced with C++ (I'm probably a basic C# programmer, with lots more experience in Javascript, PHP, HDL/Verilog and Z80 assembly than anything else).

Can anyone point me to a (simple) example of a serial interface for the LPC546xx, so I can decipher how to set up my chosen pins (probably Flexcomm 3 USART Tx/Rx on PIO0_2 and PIO0_3) and send data via the serial interface instead of to the SWD interface? I guess some simple tutorials on what I'd need to know re: C++ project management would be important too, as telling me to 'add this file to the project' may be met with a confused question...

Any help would be gratefully received - any code or step-by-steps would be massively appreciated.

Thanks in advance!

Thanks for your reply, Nino.

Sorry if I wasn't clear enough in my original question - I'm not looking to connect the emPower_USB_Host Board to my FPGA. I just got the emPower_USB_Host Board to test out the demo software and prove the concept.

I'm actually looking to build a custom PCB with an FPGA and an LPC546 on it, using the emPower_USB_Host Board schematic as a template for the LPC546 and supporting components on my custom PCB. I intend to install the embOS/emUSB-Host firmware onto the LPC546, then load in my custom USB-HID software to output the keyboard keycodes to the FPGA via the serial interface I outlined in my question.

I just need to know how to set up a simple serial interface on an LPC546. I'll take a look at those examples you've linked and see if there's anything of help in them.

Thanks!