LED RGB Strips and library

DragonSoul · November 25, 2019, 11:16am

Hello.
I’m using the library https://github.com/pololu/pololu-led-strip-avr for controll RGB strips, which is working fine.
I’m using ATMEGA64. Unfortunatelly I can’t control the RGB strips, when the control line is connected to PORTF and PORTG. As I readed, those ports are in extended register and should be handled as memory.
But I’m very bad at assembler, so I don’t know how to change the library to make it working.
Can you help me please?

DavidEGrayson · November 26, 2019, 10:08pm

Hello. I just added a new example that should work with any AVR pin.

github.com

pololu/pololu-led-strip-avr/blob/master/led_strip_ds.c

// This is AVR code for driving the RGB LED strips from Pololu.
//
// This version can control any AVR pin.  It uses "lds" and "sts" instructions,
// which means it has to write to the entire port register every time it toggles
// the I/O line, but that should be safe because interrupts are disabled.
//
// It allows complete control over the color of an arbitrary number of LEDs.
// This implementation disables interrupts while it does bit-banging with
// inline assembly.

// This line specifies the frequency your AVR is running at.
// This code supports 20 MHz, 16 MHz and 8MHz
#define F_CPU 20000000

// These lines specify what pin the LED strip is on.
// You will either need to attach the LED strip's data line to PH3
// (pin 6 on the Arduino Mega 2560) or change these
// lines to specify a different pin.
#define LED_STRIP_PORT PORTC
#define LED_STRIP_DDR  DDRC

This file has been truncated. show original

Does that work for you?

–David

DragonSoul · November 27, 2019, 9:05am

Thanks,
I will check today or tomorow.

DragonSoul · November 27, 2019, 7:52pm

Hello Mr. Grayson.
I can confirm, that following function is working with all ports.
Tested on PORTG and PORTF, tested at 8MHz.
Thank you for you effort