diff --git a/boards/relaycard.mk b/boards/relaycard.mk
new file mode 100644
index 0000000..682c7e7
--- /dev/null
+++ b/boards/relaycard.mk
@@ -0,0 +1,7 @@
+include boards/nano.mk
+
+CPPFLAGS += -DBAUDRATE=$(AVRDUDE_BAUD)
+
+ifndef PROG
+PROG = uart-relaycard
+endif
diff --git a/uart-relaycard.c b/uart-relaycard.c
new file mode 100644
index 0000000..78deee6
--- /dev/null
+++ b/uart-relaycard.c
@@ -0,0 +1,127 @@
+#include <stdio.h>
+#include <avr/io.h>
+#include <util/delay.h>
+#include <avr/interrupt.h>
+
+#define BAUD_PRESCALE (((F_CPU/(BAUDRATE*8UL)))-1)
+
+/* Button matrix between PB3-PB4, PC0-PC3
+ * PC0-PC3 are inputs, default pull-up
+ * PB3-PB4 are pulled to ground (alternating) while the above are read
+ */
+
+uint8_t getButtonState() {
+        uint8_t val = 0;
+
+        // Pull upper button line (PB4) down
+        PORTB |= (1 << PB3);
+        PORTB &= ~(1 << PB4);
+	_delay_ms(1);
+	val = ((~PINC) << 4);
+
+        // Pull lower button line (PB3) down
+        PORTB &= ~(1 << PB3);
+        PORTB |= (1 << PB4);
+	_delay_ms(1);
+	val |= (~PINC) & 0x0F;
+
+	return val;
+}
+
+uint8_t getrelay(uint8_t n) {
+	uint8_t v = 0;
+	switch(n) {
+		case 0: v = (PIND >> PD2); break;
+		case 1: v = (PIND >> PD3); break;
+		case 2: v = (PIND >> PD4); break;
+		case 3: v = (PIND >> PD5); break;
+		case 4: v = (PIND >> PD6); break;
+		case 5: v = (PIND >> PD7); break;
+		case 6: v = (PINB >> PB0); break;
+		case 7: v = (PINB >> PB1); break;
+	}
+	return(~v & 1);
+}
+
+void setrelay(uint8_t n, uint8_t s) {
+	if (s) {
+		switch(n) {
+                        case 0: PORTD &= ~(1 << PD2); break;
+                        case 1: PORTD &= ~(1 << PD3); break;
+                        case 2: PORTD &= ~(1 << PD4); break;
+                        case 3: PORTD &= ~(1 << PD5); break;
+                        case 4: PORTD &= ~(1 << PD6); break;
+                        case 5: PORTD &= ~(1 << PD7); break;
+                        case 6: PORTB &= ~(1 << PB0); break;
+                        case 7: PORTB &= ~(1 << PB1); break;
+		}
+	} else {
+		switch(n) {
+                        case 0: PORTD |= (1 << PD2); break;
+                        case 1: PORTD |= (1 << PD3); break;
+                        case 2: PORTD |= (1 << PD4); break;
+                        case 3: PORTD |= (1 << PD5); break;
+                        case 4: PORTD |= (1 << PD6); break;
+                        case 5: PORTD |= (1 << PD7); break;
+                        case 6: PORTB |= (1 << PB0); break;
+                        case 7: PORTB |= (1 << PB1); break;
+		}
+	}
+}
+
+char umode = 't';
+ISR(USART_RX_vect) {
+        uint8_t c = UDR0;
+	if (c == 't' || c == 'e' || c == 'd') {
+		umode = c;
+	} else if (c >= '0' && c <= '7') {
+		c = c - '0';
+		if (umode == 'e') {
+			setrelay(c,1);
+		} else if (umode == 'd') {
+			setrelay(c,0);
+		} else if (umode == 't') {
+			setrelay(c,1 - getrelay(c));
+		}
+	}
+}
+
+int main() {
+	DDRC &= ~(0b1111); // This sets PC0 to PC3 to input
+	PORTC |= 0b1111; // This makes said pins pull-up per default
+
+	DDRB |= (1 << PB3) | (1 << PB4); // Keypad rows
+
+	DDRD |= 0b11111100; // PD2 to PD7 for relay
+	DDRB |= 0b00000011; // PB0 and PB1 for relay
+
+	// Same with PORT, so relays stay off
+	PORTD |= 0b11111100;
+	PORTB |= 0b00000011;
+
+	// Init uart
+        UCSR0A = (1<<U2X0);
+	// Transmit is enabled to set PIN levels, but we will never write
+        UCSR0B = (1<<RXEN0) | (1<<TXEN0) | (1<<RXCIE0);
+        UCSR0C = (1<<UCSZ00) | (1<<UCSZ01); // 8N1
+        UBRR0 = BAUD_PRESCALE;
+
+	sei();
+
+	// Now handle button inputs
+	uint8_t c,p,d,i;
+	p = 0;
+
+	while (1) {
+		c = getButtonState();
+		d = c ^ p;
+		p = c;
+		for (i = 0; i<8; i++) {
+			if (d & c & 0x80) {
+				setrelay(i, 1 - getrelay(i));
+			}
+			d = d << 1;
+			c = c << 1;
+		}
+	};
+}