1435 - USB to I2C master
Description: This module provides the ability to quickly test I2C slave devices by generating all of the standard master functions compiled from a simple text script. Additionally the
GPIOs, interrupt input and delay functions allow complex control scenarios and testing of your I2C system robustness. The on board level shifting circuitry allows interface to
slave devices operating with buses between 1.5V and 5.0V.
Module Hardware Features:
- USB-B control connector and 10 pin header for I2C, GPIO and power connections.
- Bus powered module can deliver VBus and/or a programmable 0-5V @ 200mA, short circuit protected output to power the slave device and level shifter reference.
- Input and output ESD protected.
- On board level shifter with 2.2K slave side pull up resistors for slave devices operating from 1.5 to 5.5vdc.
- Read back of slave interface voltage and overload protection status.
- 3 wire connection to your slave device: Program the reference voltage to match the slave voltage while leaving the power pin unconnected.
- Four programmable general purpose I/Os: 5V CMOS logic, 25mA per output.
- I2C SCL and SDA may be bit-banged to assist in slave communication debug.
- One 16 volt tolerant interrupt input with VIL<0.7V / VIH>1.5V thresholds reports change of state and can activate stored command on rising or falling edge for instant interrupt driven recorded I2C script communication.
Module Firmware Features:
- On-the-fly selectable 100kbps (Slow) or 400kbps (fast) I2C protocol: Timing example.
- Communication via USB virtual com port at 115.2kbps.
- Speed and interrupt configuration saved on power down.
- Commands are ASCII hex, allowing control via GUI, terminal program or user software interface.
- Tokenized command length from 1 to 250 elements: Example above is 16 elements.
- Tokens interpreted and processed at full bus speed, then response data is sent to minimize I2C bus inter character delays or latency.
- Last command sequence can be stored in on board EEPROM which may then be activated upon selectable rising or falling edge of interrupt input or on command.
- Stored command sequence retains speed information independent of current speed selection.
- Preloaded sample commands to talk to an LM75 temperature sensor.
- Simple script entry, clicking on a token from the list inserts it at the end of the script.
- Load user scripts from text file into the drop down selection list: LM75 script / Simple script.
- First 18 commands loaded from the user file populate quick access buttons for easy one or two click access.
- Tokens may be entered into the script list or executed immediately.
- Command queue is parsed into token stream with result shown in transmit window.
- Connector button shows pin out of target connector.
- Help button shows description of controls as well as detailed protocol data.
- Both command data to the module and module responses displayed to assist user communicaton developement
Included in Package:
- I2C Master USB Module.
- 10 pin IDC ribbon connector.
User manual accessible with "Help" button: