I2C-RPT-08

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Tindie-mediums.png

I2C-RPT-08-X1-P218-720px.jpg

Features[edit]

  • I2C Hub / Repeater / Replicator / Multiplexer / De-multiplexer / Switch
  • Host port
    • Controlled via I2C
    • 3.3V or 5V host operation
    • Can power slave cards if they are at the same voltage
  • 3.3V or 5V slave ports operation
    • Removable jumper(s) to supply power from slave
  • Voltage translation between the ports
  • Ex: a Raspberry Pi which runs 3.3V can control I2C devices which run at 5V
  • On-board 2.2K termination resistors
  • 49x49mm form factor
  • 4 solid 4-40 mounting holes

Connectors[edit]

I2C-RPT-08-X1-Conns-P218-720px.png

H1-H8 - Power to/from I2C Connectors[edit]

  • Install shunt to power the I2C slave card from the I2C-RPT-08 Card
    • Default factory ships as installed to power external I2C interfaces from the card
  • H1 - PORT #0
  • ...
  • H8 = PORT #7

Host I2C Connection[edit]

  1. GND (GND pin marked)
  2. 3.3V or 5V VCC
  3. SDA
  4. SCL

Slave I2C Connections (x8)[edit]

  1. GND
  2. 3.3V or 5V VCC (Power Out - if jumper 1-2 installed, Power in - if jumper 1-2 is not installed)
  3. SDA
  4. SCL (Board marked with SCK)

Jumpers[edit]

A0-A2 - Multiplexer I2C Base Address[edit]

  • Install for Ax = 0 (factory default address = 0)
  • Remove for Ax = 1

Schematic[edit]

Drivers/Example Code[edit]

Programming Note[edit]

  • The mux chip allows multiple or single I2C ports to be written at the same time
    • To only enable one port at a time make sure you disable a channel after use or disable last channel used before enabling new channel

Testing[edit]

P963-cropped-720px.jpg

Issues[edit]

  • Silkscreen shows SCK, should be SCL

Assembly Sheet[edit]