More experiments,

add LICENSE

LICENSE

@@ -0,0 +1,26 @@
+Copyright (c) 2019, Mark Robson
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+The views and conclusions contained in the software and documentation are those
+of the authors and should not be interpreted as representing official policies,
+either expressed or implied, of the Malenki-ESC project.

firmware/README.md

@@ -16,3 +16,7 @@ pyupdi can be used with a simple serial cable + 1 resistor.
 
 See https://github.com/mraardvark/pyupdi/
 
+Useful examples:
+
+https://github.com/chromia/attiny1614example
+

firmware/demo1/PIN_ASSIGNMENTS.txt

@@ -0,0 +1,47 @@
+Pin assignments / usage
+
+PA0 - RESET / UPDI - default - not used by code. Used for programming
+	firmware, wired to a pogo pin on underside.
+PA1 - UART0 TxD - used for diagnostic serial output.
+	connected to pin 3 of the pogo pins J6 on underside of board.
+
+PA2 - UART0 RxD - connected to the RXIN connection.
+	This is used to receive either PPM signals, or serial
+	from the radio.
+
+PA3 - Motor1F (Weapon)
+PA4 - Motor3R (Right)
+PA5 - Motor3F (Right)
+
+PA6 - BLINKY - high for blue LED, low for red LED.
+PA7 - VSENSE - senses battery voltage.
+	This is connected to two resistors pulled down by 10k, pulled up by 33k.
+	So it will give the voltage of approximately VBAT * (10 / 43)
+	Or approx 1/4 of the bat voltage.
+
+PB0 - Motor1R (Weapon)
+PB1 - Motor2R (Left)
+PB2 - Motor2F (Left)
+
+PB3 - Unused
+
+Peripheral usage
+
+USART0 - transmitter - for debug messages
+	receiver - to receive digial data from rx
+
+TCA0 - timer generates 6x PWM pulses on motors
+	use in "split mode"
+
+TCB0 - Count the pulse width on PA2 for pulse input
+	could generate irq when pulse ends
+TCB1 - Generate periodic interrupts
+	- so that we can increment a time counter
+	to run periodic tasks every so often
+
+TCD0 - unused
+
+EVENTSYSTEM - need to route event from pin PA2 to
+	the TCB0 to sense pulses.
+
+ADC - need just one channel to read bat. voltage

firmware/demo1/main.c

@@ -9,7 +9,7 @@
 char unused1;
 unsigned char somestorage[10];
 
-void init_ports_out()
+void init_hardware()
 {
 	// Set all the ports which need to be outputs, to be outputs.
 	// should all be low initially.
@@ -23,6 +23,19 @@ void init_ports_out()
 	PORTB.DIRSET = 1 << 0;
 	PORTB.DIRSET = 1 << 1;
 	PORTB.DIRSET = 1 << 2;
+
+	// Timer A = generate PWM on thos pins
+
+	// UART0- need to use "alternate" pins 
+	// This puts TxD and RxD on PA1 and PA2
+	PORTMUX.CTRLB = 1; // Bit 0 = alt. usart pins
+
+	// TxD pin is used for debug, should be an output
+	PORTA.DIRSET = 1 << 1;
+
+	//
+	// Timer A should be in split mode
+	//
 }
 
 void init_timer_interrupts()
@@ -46,7 +59,7 @@ ISR(TCB0_INT_vect)
 int main(void)
 {
 	memset(somestorage, 0, sizeof(somestorage));
-	init_ports_out();	
+	init_hardware();	
 	init_timer_interrupts();
 	sei();  // enable interrupts
 	_delay_ms(100);