Model JI-300
USB to I2C Adapter
Features
Programmable SCL clock frequency from 255Hz to 3.8Mhz (20nS steps)
Supports Standard-mode, Fast-mode, Fast-mode-Plus, and High-Speed-mode
Variable bus voltage from 1.50V to 5.25V (10mV steps)
Software selectable bus pull-up resistors (16 values including open)
USB 2.0 host interface
Switched target bus voltage at connector
I2C Device Discovery Utility
Easy to use Graphical User Interface (GUI)
  • I2C Message Controller
    - Message execution status - Success / Failure w/ details
  • EEPROM Programming Utility
     - Programming file formats include: Binary, Intel HEX, Motorola S-record  
Create custom software applications using either direct or Virtual COM Port
(VCP) drivers. Programming requires
no in-depth knowledge of USB!
Includes everything needed to get started – I2C Adapter unit, I2C cable, USB
cable, and a CD-ROM containing application software and user’s manual.
Applications
Firmware debugging and hardware troubleshooting.
Production-line testing.
Equipment repair and diagnostics.
Main Window
Add I2C Message Menu
EEPROM Programming Utility
Documents and Downloads
Front View
Rear View
HS I2C Cable
Software Driver Links
Questions or comments?  Please email or call:
sales@jupiteri.com
or  Ph: 949-716-0154
Jupiter Instruments                                                                                                                                                               www.jupiteri.com
Updated on 1/25/17
The JI-300 is a versatile, easy to use PC hosted adapter used to drive I2C communications
to/from a target device. The desktop unit can be configured to interface a variety of I2C
networks.  Bus parameters such as clock frequency, duty-cycle, setup and hold times, bus
voltage, and pull-up resistor values can be varied. JI-300’s diagnostic features including
“excessive clock-stretch”, “bus-not-free”, and “bus contention” monitoring, as well as status
reporting at the conclusion of each message transaction simplifies I2C trouble-shooting. A
Windows software application manages the setup and control of the instrument.
Communications and unit power is provided via a USB 2.0 connection.
USB to I2C Adapter
    - Single-step execution option
    - Message looping
JI-300 Specification
Programer's Interface Document (pdf 202KB)
Date
Version
1.6
11/24/14
6/15/12
1.4a
Documents
Direct Drivers - DLLs
USB Programmer's Guide
Date
Version
5.4A
3/6/15
Software
Application Software
Date
Version
---
3/2/11
Programming Examples
JI-300 Simple Programming Example (zip 1056KB)
User's Manual
1.6
11/2/12
Application Software - Demo (zip 106K)
2.2
9/05/08
Project File (C#) - Simple Programming
Example (zip 187KB)
---
3/2/11
Virtual COM Port
Software Demo
Scripting with the JI-300
2/16/11
---
Jupiter Instruments
Unique instrumentation products
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Software Demo
Model JI-300
  • Data Logging - Select continuous or scheduled
Setup Files (STD_24C04_Ex1.ser & HS_MCP4725_Ex2.ser)
---
11/2/12
Tab 3
Tab 2
Tab 1
Tab 4
Selectable SDA/SCL drive current (10mA, 20mA, or 30mA)
I2C Device Discorvery
Video Demo
New!