Week

seven

embeded programming

embeded programming 🔦

highlights

Attiny44 button blink USBtinyISP as Programmer
Find some interesting mistake on my homebrew CNC pcb mill Summerized some tips for designer used arduino before to jump on to programming Attiny in C

Attiny44 echo program
had some questions about using 8mhz resonator.

Attiny44 button blink Arduino as Programmer
easy peasy

usbtinyISP
as programmer

push button blink program with USBtiny ISP

notes for designers used arduino before

1.Read Data sheet to know if the Pin is located on A/B
DDRA/B = 0b00000001 (1st pin set as output)
PORTA/B = 0b00000001(1st pin set as high)
PINA/B & 0b0010000 (to get data from 5 bits from A)
2.Arduino PinMode/Digital Read/Digital Write Replacement in C:
//Preamble
#define bit_get(p,m) ((p) & (m))
#define bit_set(p,m) ((p) |= (m)) //no idea why OR is necessary
#define bit_clear(p,m) ((p) &= ~(m)) //no idea why AND is necessary
//main
bit_set(DDRA,BIT(7)); //Enable output on the LED pin
if(bit_get(PINA,BIT(3)))//button is pushed or not
bit_clear(PORTA,BIT(7));//LED is off
3.Bit Shift
#define output_pin (1 << PB2) // output_pin = 0b00000100 ( 1<<2)
//so btw is “PB” ignored?

The first time I use my home brew PCB mill and I found out I install one motor on the wrong side and the result circuit is mirrored lol

the setup if using mac 2017 ver. make sure you have usb 2.0 for everything

code loaded

The left is button pushed and swing the board. The led is blinking so fast that people hardly recongnized when staring at. Through swinging it, it's revealed as dash line in the air (from Elliot Williams's AVR programming)

Attiny 44
echo program

attiny 44 echo program
why can't be run on 8mhz?

echoing using arduino serial monitor, works perfectly using the board with 20mhz resonator

using a board with 8mhz resonator, I changed the make file to 8mhz, but it didn't echo on all BAUD channel. Why changing clock speed influnce the program