USBFTDIPassthru.ino

/*
 * Edited by Robert Woodruff 2021
 * From the USBFTDILoopback.ino example provided with the USB Host Shield 2.0 library
 * https://github.com/felis/USB_Host_Shield_2.0
 * Released under GNU General Public License
 * 
 * This example will check the UART receive buffer once every program loop
 * If data is available, one byte will be read in and sent to the MAX3421E
 * 
 * The MAX3421E USB receive buffer will be checked once every program loop
 * If data is available, 0 - 62 bytes will be retrieved and sent over UART
 */

#include <cdcftdi.h>
#include <usbhub.h>

#include "pgmstrings.h"

// Satisfy the IDE, which needs to see the include statment in the ino too.
#ifdef dobogusinclude
#include <spi4teensy3.h>
#endif
#include <SPI.h>

class FTDIAsync : public FTDIAsyncOper
{
public:
    uint8_t OnInit(FTDI *pftdi);
};

uint8_t FTDIAsync::OnInit(FTDI *pftdi)
{
    uint8_t rcode = 0;

    rcode = pftdi->SetBaudRate(115200);

    if (rcode)
    {
        ErrorMessage<uint8_t>(PSTR("SetBaudRate"), rcode);
        return rcode;
    }
    rcode = pftdi->SetFlowControl(FTDI_SIO_DISABLE_FLOW_CTRL);

    if (rcode)
        ErrorMessage<uint8_t>(PSTR("SetFlowControl"), rcode);

    return rcode;
}

USB              Usb;
//USBHub         Hub(&Usb);
FTDIAsync        FtdiAsync;
FTDI             Ftdi(&Usb, &FtdiAsync);

void setup()
{
  Serial.begin( 115200 );
#if !defined(__MIPSEL__)
  while (!Serial); // Wait for serial port to connect - used on Leonardo, Teensy and other boards with built-in USB CDC serial connection
#endif
  Serial.println("Start");

  if (Usb.Init() == -1)
      Serial.println("OSC did not start.");

  delay( 200 );
}

void loop()
{
    Usb.Task();

    if( Usb.getUsbTaskState() == USB_STATE_RUNNING )
    {
        uint8_t  rcode;
        char strbuf[2] = "";

        if (Serial.available())
        {
            // Read character from UART buffer
            strbuf[0] = Serial.read();
            // Echo character to terminal
            Serial.print(strbuf[0]);
            // Add LF after a CR
            if (strbuf[0] == '\r') {
                Serial.print('\n');
            }      

            rcode = Ftdi.SndData(strlen(strbuf), (uint8_t*)strbuf);
    
            if (rcode)
                ErrorMessage<uint8_t>(PSTR("SndData"), rcode);

            // delay(50);
        }

        uint8_t  buf[64];

        for (uint8_t i=0; i<64; i++)
            buf[i] = 0;

        uint16_t rcvd = 64;
        rcode = Ftdi.RcvData(&rcvd, buf);

        if (rcode && rcode != hrNAK)
            ErrorMessage<uint8_t>(PSTR("Ret"), rcode);        

        // The device reserves the first two bytes of data
        //   to contain the current values of the modem and line status registers.
        if (rcvd > 2)
        {
            // Print buffer at once
            // Serial.print((char*)(buf+2));

            // Print buffer characters individually
            for (uint8_t i = 2; i < rcvd; i++)
            {
                Serial.print((char)buf[i]);
                // Check for newline
                if (buf[i] == '\n') {
                    // Add return
                    Serial.print('\r');
                }
            }                      
        }

        // delay(10);
    }
}