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kroy-the-rabbit/usbtoserial.ino

Last active July 14, 2021 16:12
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usb->serial
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usbtoserial.ino
#include <Usb.h>
USB Usb;
// Human Interface Device
#include <hidboot.h>
HIDBoot<HID_PROTOCOL_MOUSE> HidMouse(&Usb);
/* Pin where we received the RTS signal from pin 7 on DB9 */
#define RTS_PROBE 3
/* Flash a LED on startup/moused-up */
#define LED 13
/* MS Mouse protocol */
#define USE_MS_PROTOCOL
/* print out debug stuff, which will definitely break mouse function */
// #define DEBUG
// ----- Mouse Report Parser
class rpt : public MouseReportParser
{
public:
/* Status variables for keeping track of button/probe states */
bool left_status = false;
bool right_status = false;
bool middle_status = false;
bool rts_status = false;
bool left_changed = false;
bool right_changed = false;
bool middle_changed = false;
bool event = false;
bool event_mb = false;
int x_status = 0;
int y_status = 0;
protected:
void OnMouseMove (MOUSEINFO *mi);
void OnLeftButtonUp (MOUSEINFO *mi);
void OnLeftButtonDown (MOUSEINFO *mi);
void OnRightButtonUp (MOUSEINFO *mi);
void OnRightButtonDown (MOUSEINFO *mi);
void OnMiddleButtonUp (MOUSEINFO *mi);
void OnMiddleButtonDown (MOUSEINFO *mi);
};
void rpt::OnMouseMove(MOUSEINFO *mi)
{
x_status = mi->dX;
y_status = mi->dY;
event = true;
};
void rpt::OnLeftButtonUp (MOUSEINFO *mi)
{
//Serial.println("L Butt Up");
left_status = false;
left_changed = true;
event = true;
};
void rpt::OnLeftButtonDown (MOUSEINFO *mi)
{
left_status = true;
left_changed = true;
event = true;
};
void rpt::OnRightButtonUp (MOUSEINFO *mi)
{
right_status = false;
right_changed = true;
event = true;
};
void rpt::OnRightButtonDown (MOUSEINFO *mi)
{
right_status = true;
right_changed = true;
event = true;
};
void rpt::OnMiddleButtonUp (MOUSEINFO *mi)
{
middle_status = false;
middle_changed = true;
event = true;
event_mb = true;
};
void rpt::OnMiddleButtonDown (MOUSEINFO *mi)
{
middle_status = true;
middle_changed = true;
event = true;
event_mb = true;
};
rpt Prs;
/* Serial mouse packet encoding routine */
/* Encodes a 3 byte mouse packet that complies with Microsoft Mouse/Logitech protocol */
void encodePacket(int x, int y, bool lb, bool rb, unsigned char* output)
{
/* Cap values just in case to avoid overflow errors */
if ( x > 127 )
{
x = 127;
}
else if ( x < -127 )
{
x = -127;
}
if ( y > 127 )
{
y = 127;
}
else if ( y < -127 )
{
y = -127;
}
char cx = x;
char cy = y;
/* Packet 0 */
output[0] = ((cx>>6)&0x3) | /* last 2 bits of X */
(((cy>>6)&0x3)<<2) | /* Last 2 bits of Y */
(rb<<4)|(lb<<5)|0x40; /* Mouse buttons and start packet bit */
output[1] = cx&0x3f; /* Packet 1 ( first 6 bits of X ) */
output[2] = cy&0x3f; /* Packet 2 ( first 6 bits of Y ) */
}
void setup()
{
/* Set pin for RTS probe as input */
pinMode( RTS_PROBE, INPUT );
/* For blinking LED */
pinMode( LED, OUTPUT );
digitalWrite( LED, LOW );
Serial.begin( 1200, SERIAL_7N1 );
// Inititialise USB card
Usb.Init();
HidMouse.SetReportParser(0, &Prs);
/* Flash LED to indicate adapter is ready */
delay( 500 );
for ( int i=0; i<4; i++ )
{
digitalWrite( LED, HIGH );
delay( 200 );
digitalWrite( LED, LOW );
delay( 200 );
}
}
void loop()
{
Prs.event = false;
Prs.event_mb = false;
Prs.left_changed = false;
Prs.right_changed = false;
Prs.middle_changed = false;
int data[2];
unsigned char packet[4];
int p_count = 3;
int ctr = 0;
/* Drop some packets. USB is WAAAAAY too fast for serial */
do
{
Usb.Task();
ctr++;
} while (ctr < 475);
/* Divide velocity values to smoothen the movement */
int x_status_d = Prs.x_status; // / 2;
int y_status_d = Prs.y_status; // / 2;
/* Reset X Y counters when divided result is non-zero */
if ( x_status_d != 0 )
{
Prs.x_status = 0;
Prs.event = true;
}
if ( y_status_d != 0 )
{
Prs.y_status = 0;
Prs.event = true;
}
/* Send mouse events if there's any */
if ( Prs.event )
{
#ifdef DEBUG
Serial.print( "LB:" );
Serial.print( Prs.left_status );
Serial.print( " RB:" );
Serial.print( Prs.right_status );
Serial.print( " MB:" );
Serial.print( Prs.middle_status );
Serial.print( " X:" );
Serial.print( y_status_d );
Serial.print( " Y:" );
Serial.print( y_status_d );
Serial.println();
#endif
/* Encode the packet */
encodePacket( x_status_d, y_status_d,
Prs.left_status, Prs.right_status, packet );
/* Send extra byte for the middle mouse button status */
#ifndef USE_MS_PROTOCOL
if ( Prs.middle_status )
{
packet[3] = 0x20;
p_count = 4;
}
else
{
/* 4th byte is sent once when middle button is lifted */
if ( Prs.event_mb )
{
packet[3] = 0x0;
p_count = 4;
}
}
#endif
/* Send packet */
#ifdef USE_SERIAL1
Serial1.write( packet, p_count );
#else
Serial.write( packet, p_count );
#endif
}
#ifdef USE_MS_PROTOCOL
// Send blank packet for middle mouse status
if ( Prs.middle_changed )
{
packet[0] = 0x40;
packet[1] = 0x00;
packet[2] = 0x00;
p_count = 3;
#ifdef USE_SERIAL1
Serial1.write( packet, p_count );
#else
Serial.write( packet, p_count );
#endif
}
#endif
/* Send init bytes when RTS has been toggled */
if ( digitalRead( RTS_PROBE ) )
{
if ( !Prs.rts_status )
{
#ifdef DEBUG
Serial.print("Send init byte!\n");
#endif
delay(14);
#ifdef USE_SERIAL1
Serial1.write( 'M' );
#else
Serial.write( 'M' );
#endif
delay(63);
#ifndef USE_MS_PROTOCOL
#ifdef USE_SERIAL1
Serial1.write( '3' );
#else
Serial.write( '3' );
#endif
#endif
Prs.left_status = false;
Prs.right_status = false;
Prs.middle_status = false;
Prs.rts_status = true;
digitalWrite( LED, HIGH );
delay( 500 );
digitalWrite( LED, LOW );
}
}
else
{
Prs.rts_status = false;
}
}
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