I2C-RPT

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Tindie-larges-v2.png

I2C Repeater (I2C-RPT-01)

Connect more than one I2C device with the same address to your microcontroller.

Here is the page for the I2C-RPT-01 Rev X1 card.

I2C-RPT-01 X1vsX2-CCA-720px.jpg

I2C-RPT-01-X2-CCA 6031-640px.jpg

Features

  • I2C Hub / Repeater / Replicator / Multiplexer / De-multiplexer
  • Four I2C Ports
  • Host port
  • Controlled via I2C
    • I2C address = 0x70
  • PCA9544A IC
    • Multiple vendors
  • 3.3V or 5V host operation
  • 3.3V or 5V slave ports operation
  • Voltage translation between the ports
    • A Raspberry PI which runs 3.3V can control an I2C device which runs at 5V
  • Interrupt line on each channel and host
  • 100KHz/400KHz operation
  • On-board termination resistors
  • 49x49mm form factor
  • 4 solid 4-40 mounting holes

Connectors

  • J1-J5 are 0.1" pitch, right-angle connectors

J1 - I2C #0

  1. Ground
  2. Vcc - Jumper determines whether pin provides or receive power
  3. SCL
  4. SDA
  5. INT*

J2 - I2C #1

  1. Ground
  2. Vcc - Jumper determines whether pin provides or receive power
  3. SCL
  4. SDA
  5. INT*

J3 - I2C #2

  1. Ground
  2. Vcc - Jumper determines whether pin provides or receive power
  3. SCL
  4. SDA
  5. INT*

J4 - I2C #3

  1. Ground
  2. Vcc - Jumper determines whether pin provides or receive power
  3. SCL
  4. SDA
  5. INT*

J5 - I2C Host I/F

  1. Ground
  2. Vcc - power input - power the card on this pin
  3. SDA
  4. SCL
  5. INT*

Power Configuration Jumpers

  • The I2C interfaces can be configured to be on different voltages.
    • The jumper by each connector allows the external power to be isolated from the I2CRPT01 card.
    • If the jumper is installed power will be sourced from the I2CRPT01 card.
    • If the jumper is removed power will be isolated between the I2C Target and the I2CRPT01 card.

H1 - I2C #0 Power

  • Install to power this I/F from the Host power
  • Remove jumper to power interface from J1 5 pin connector

H2 - I2C #1 Power

  • Install to power this I/F from the Host power
  • Remove jumper to power interface from J2 5 pin connector

H3 - I2C #2 Power

  • Install to power this I/F from the Host power
  • Remove jumper to power interface from J3 5 pin connector

H4 - I2C #3 Power

  • Install to power this I/F from the Host power
  • Remove jumper to power interface from J4 5 pin connector

Drivers

PCA9544_Programming

Arduino Library

Raspberry Pi Example

BeagleBone Black Driver

Layout

I2C-RPT-01-X3.png

Assembly Sheet

I2C-Assy-Sheet

Factory Test Procedure

  • Blue Pill Hub card
    • 1 pin goes to Arduino D9 (interrupt)
    • Port 0 goes to UUT J5
  • (4) I2CIO-8 I2C targets
    • MCP23008 8-bit I2C port expanders
    • 4 LEDs and 4 input jumpers
    • Interrupt line programmed to activate on input change
    • All set to address 0
    • Terminators disabled
    • Jumper on input
  • UUT (I2C-RPT-01)
  • Cables
    • 4x 1:1 5-pin cables
      • Connect between J1-J4 and the I2C connectors on each I2CIO-8 card
  • Running ODAS Test Software
  • Serial monitoring COMxx at 9600 baud
  • Light will bounce across LEDs and cards
  • Remove/install input Input jumper on each card
    • Observe Serial messages for each port

Checkout Notes

  • UUT is Rev X2 card

Hardware

Future Improvements

  • Add multiplexer I2C offset addressing