megadmx

Minimalistic DMX & ArtNet projects using the ATmega8

• ArtNet to DMX bridge using an ATmega8 and an ENC28J60
• DMX receiver with PWM outputs using an ATmega8 and a MAX481
• DMX receiver with PWM outputs using an ATtiny13 and a MAX481

In order to properly receive DMX data, the oscillator must run at 8MHz, either by supplying an external clock source or flashing the fuse bytes to provide this via the internal oscillator.

A target to flash the respective controllers to an 8MHz internal clock is provided in the respective makefiles.

Hardware Setup

Bridge

MAX485 DI	<->	PD1 (UART TX)
MAX485 DE/RE	<->	HIGH
LED1		<->	PC5
LED2		<->	PC4
ENC CS		<->	PB0
ENC INT		<->	PB1
ENC SPI		<->	ATmega SPI
ATmega SS	<->	HIGH
ENC RST		<->	HIGH
ENTER button	<->	PD0
UP button	<->	PD2
DOWN button	<->	PD3
SSD1306 SPI	<->	ATmega SPI
SSD1306 CS	<->	PC3
SSD1306 DC	<->	PC2
SSD1306 RES	<->	PC1

Receiver (mega8)

MAX481 RO	<->	PD0 (UART RX)
MAX481 DI/DE/RE <->	LOW
DMX ADDR	<->	PC012345 PD567
PWM OUT		<->	PB123

Receiver (tiny13)

MAX481 RO	<->	PB3
MAX481 DI/DE/RE <->	LOW
PWM OUT		<->	PB01
ADDRSWITCH	<->	PB2

Hold the ADDRSWITCH down to set the channel addresses
to the first two DMX channels with value > 127