DIGIO-128
Contents
Features
- 128 bits of General Purpose Digital I/O (GPIO)
- Card uses I2C addresses 0x20-0x27 for I/O and 0x50 for Configuration EEPROM
- (8) of MCP23017 - 16 bit GPIO
- I2C (Two Wire) host interface
- 100/400 KHZ operation
- 25mA sink/source capability per I/O
- Limited by current in/out of the IC
- 24LC024 Configuration/Personality EEPROM
- Jumper selectable I2C terminators
- Single 4-pin host interface connector (Ground, Power, Clock, Data)
- (8) I/O Connectors
- 20 pin, 0.1" Pitch
- 16 digital I/O
- 2 Power
- 2 Ground
- Interrupt connectors
- Power Connector
- 3.3V or 5V operation
- 24LC024 I2C Personality EEPROM
- Compatible with Arduino, Raspberry Pi, BeagleBone Black
- 95x95mm form factor
- (4) 6-32 mounting holes - one on each corner
I2C Addresses
- MCP23017 parts 0x20 - 0x27
- EEPROM 24LC024 = 0x50
Connectors
P1-P4, P6-P9 - Digital I/O Connectors
- 16 bits per connector
- (2) Power
- (2) Ground
P5, P10 - Interrupt Outputs
- Useful for detecting input changes or levels
- Can be ignored if not needed
- If the inputs are polled, the pins can be ignored
J1 - External Power
- Can be ignored if the card is powered through I2C connector
J2, J3 - I2C Connectors
- Daisy chained connections
- 2nd connector can be ignored
- Card can be powered through this connector(s)
- MCP23017 parts use I2C slave addresses 0x20-0x27
- EEPROM 24LC024 parts use I2C slave address 0x50
- Can't use more than one DIGIO-128 per I2C bus without separating busses with an I2C multiplexer
- I2C-RPT - Land Boards 4-Channel I2C Multiplexer/Repeater
- I2C-RPT-08 - Land Boards 8-channel I2C Multiplexer/Repeater
J4 - I2C Terminators and EEPROM Write Enable
- SDA, SCL I2C Terminators
- Install jumper to use terminators
- WE - EEPROM Write Enable
- Install To enable writing config EEPROM
Schematics
Testing
Software Examples/Drivers
- DIGIO-128 Arduino example code
- DIGIO-128 Arduino Driver
- DIGIO-128 - 64-bit version Arduino Driver
- DIGIO-128 Micropython Driver (ESP-32)
- Raspberry Pi Example Code - Requires some knowledge of the MCP23017 (datasheet)