Week 8 - Embedded programming
After making a programmer and a board it is time to write a little program and transfer it to the board. The chip, I am using, is the ATTiny 44 SSU. It is a 8 Bit chip, that is important to know for the baud rate, if communicating via serial port (USB). A baud is bits/second. For USB it is 115200 baud. In week six I figured out the right delay time of 7.85 µs to communicate with my board. For using it right now, I need to write a c-code and a make file and upload it with my programmer. I used the FABISP USBtiny and the smae routine, as for programming the helloechoworld program.
Blink
My first program was to make the LED blink. First I wanted to try interrupts but I ended up using the delay command.
Switch
My second program uses the switch in the board. The LED lights up, as soon as the swicht-button is pressed.
What the code does, is making all A registers inputs, except PA7. In the while loop the 3rd register
(button) is read and moved 4 bits to the left, to PA7. If PA3 is high, then PA7 is high and the LED is on.