DIGIO32-I2C

Features

• 32-bit Digital I/O
  • Two MCP23017 16-bit I2C I/O Expanders
• 24LC024 Configuration/Personality EEPROM
  • Write Enable jumper protects EEPROM against accidental damage
• I/O Connector is inexpensive/standard DB-37 Female
• I2C Interface
  • Daisy-chain I2C connector
  • I2C Termination jumpers for end of I2C chain
  • I2C Address select jumper (2 addresses - can support up to 4 cards)
• Power Options
  • Supports 3.3V or 5V signal levels
  • Fuse protected power output on DB-37
• Power connector (not required for minimal loads
• ODAS form factor (width is 95 mm)
• 6-32 Mounting holes

Connectors

DB-37 Female Pinout

Schematic

• DIGIO32-I2C Schematic

Testing

• There are two card tests
  • Bounce LED test
    • Good for visual verification/debugging
    • Only tests outputs from UUT
  • Card to card test
    • More flexible/faster test
    • Tests both inputs/outputs from/to the card

Cards

• Arduino Based Test Station
  • Black Pill Hub
  • A copy of this card (not used for bounce LEDs test)
  • LED-32
• DB37RIBBON plugged into UUT
• (2) of 2x10 cables to connect between DB37RIBBON and LED-32
  • DB37-1 marked on cable end goes near P1 marked on DB37RIBBON
• LED32-1 marked on cable end goes near HDR1 marked on LED-32
• I2C cable from Arduino Based Test Station to I2C connector on UUT
• Unit Under Test (UUT)
• Check chip pin 1 orientation
• Power test card for shorts

Card Test Procedure

• Connect USB-C to Test Station
• Run puTTY on PC
  • Select serial port
    • Find COMx using Device Manager
  • 9600 baud

Program EEPROM

• Run ODASTESTER Software
  • Type E to select EEPROM menu
  • Type W to write EEPROM
  • Type 5 to select DIGIO32-I2C card
  • Type X to exit to top level menu

Bounce LED Test

• Type C to select card test
• Type B to bounce LED across the UUT card
• Should see the LEDs go around the LED-32 card
• Hit any key to stop (after finishing rotation)

Card-to-Card Test

• Can be used in place of the Bounce LED test
• (2) DB37RIBBON cards
• Cables to connect two DB37RIBBON cards
• Type C to select card test
• Type T to test the card
• puTTY will display test pass/fail
• Can set L for loop test then T to run test
• Mark bottom TEST block on bottom of card

Code Header

  //////////////////////////////////////////////////////////////////////////////////////
  // uint8_t testDigio32Card() - Test the DIGIO32 card.
  // The Test Station and the UUT both are DIGIO32 cards.
  // Cable from UUT DB-37 connector to the DIGIO32 card DB-37 in the Test Station.
  // The DIGIO32 internal to the Test Station is set to all inputs with pull-ups.
  // The DIGIO32 that is the UUT is set up to all outputs.
  //////////////////////////////////////////////////////////////////////////////////////

Drivers

• GitHub repo for the DigIO32-I2C Card Arduino Driver
  • Importing an Arduino ZIP library
• GitHub repo for the DigIO32-I2C Card Arduino examples

Assembly Sheet

• DIGIO32-I2C Assembly Sheet