Hardware
The Reef Angel Controller kit is based on a very known and widely used microcontroller (uC) called ATMega328P. It is the same uC used on the Arduino boards, an open source electronics prototyping platform.
Click here to download the Eagle files
The uC pins used by Reef Angel Controller kit are:
PB0: 1-wire network
PB1: Daylight PWM
PB2: Actinic PWM
PB3: Low ATO
PB4: High ATO
PB5: Joystick select button
PB6: XTAL1
PB7: XTAL2
PC0: Joystick vertical signal
PC1: Joystick horizontal signal
PC2: Buzzer
PC3: N/C
PC4: I2C data
PC5: I2C clock
PC6: PH circuit input
PC7: N/C
PD0: Serial UART RX
PD1: Serial UART TX
PD2: LCD Backlight
PD3: LCD SPI Chip Select
PD4: LCD SPI Clock
PD5: LCD SPI Data
PD6: LCD Reset
PD7: Status LED
1-Wire Network
DS18B20 - Temperature sensors configured to read at 12-bit precision. The address of each sensor is unique and etched into the chip.
I2C Network
24LC256 - The 2 banks of 32K EEprom.
I2C address 0x50 is allocated to one EEprom, which has read and write enabled all the time.
I2C address 0x54 is allocated to one EEProm, which has read only or read/write enabled set by jumper JP1.
JP1 on = read/write
JP1 off = read only
DS3231 - High precision real time clock with built in oscilator.
I2C address 0x68
PCF8574 - 8 port I/O expander
I2C address 0x20 is allocated to one expander, which comes with the kit.
I2C address 0x21 is allocated to one expander, which does not come with kit, but can be soldered to expand general I/Os to 18.
