The software distributed with and the firmware contained in this product is Copyright (c) 2003 by Industrologic, Inc.

Industrologic, Inc. reserves the right to change any product's features, specifications, documentation, warranties, fee schedules, and conditions at any time and without notice.

Industrologic products are provided as printed circuit board level assemblies. Some Industrologic products may include mechanical packaging assessories which are provide for the purchaser's convenience, and are not intended to be final assembly enclosures.

Industrologic products are provided with the understanding that the purchaser will determine fitness for any particular application as well as achieve compliance with any particular specifications or regulations as required or desired for that application.

Industrologic's obligation under this Warranty is limited to replacement with a new or repaired unit to the original purchaser. The unit must be returned, and replacements obtained from Industrologic, Inc. or the Distributor or OEM from whom it was purchased.

This warranty will not apply if, in the judgment of Industrologic, Inc., damage or failure of the product has resulted from accident, alteration, misuse, abuse, connection to or operation with incompatible signals or power sources, or improper installation.

Under no circumstances shall Industrologic, Inc. be liable to purchaser or any third party for any loss of profits or other direct or indirect costs, expenses, losses, or consequential damages arising out of or as a result of any defects in or failure of Industrologic products or any part or parts thereof.

THIS WARRANTY IS IN LIEU OF ANY OTHER WARRANTY, EITHER EXPRESSED OR IMPLIED, AS TO DESCRIPTION, QUALITY, MERCHANTABILITY, FITNESS FOR ANY PARTICULAR PURPOSE OR USE, OR ANY OTHER MATTER.

Products must be returned by original purchaser with a Return Materials Authorization (RMA) number issued by Industrologic, Inc. or the Distributor or OEM from whom it was purchased, authorizing its return. Current repair or replacement fees and procedures will be related during the issue of the RMA number.

Warranty or repair units must be returned with postage and insurance paid by purchaser. Industrologic, Inc. is not responsible for damages or loss during shipment.

The SI51 includes, pre-programmed into the microcontroller, a special version of Industrologic's simple programming language, Tiny Machine Basic, written for the hardware on the SI51. By using this language the user can quickly and easily program the SI51 to perform a number of tasks, including controlling the digital I/O lines or sending character strings to a host computer in response to contact closures. The microcontroller chip can also be re-programmed using any number of software development tools available for similar Atmel microcontrollers.

• Based on the Atmel AT89C4051 microcontroller operating at 11.0592 MHZ
• 16 switch/contact closure inputs with LED indicators to show on/off status
• 4 digital logic levels signals usable as inputs or outputs including one interrupt signal
• Convenient screw terminal block connections for all contact closure and digital I/O connections
• Serial RS-232 port with true RS-232 interface and DB9F connector matching PC compatibles
• General purpose software readable pushbutton switch and software controllable LED
• 512 byte EEPROM for storage of small programs or configuration information
• On-board +5 volt power supply including screw terminal connection for external circuitry
• Pin-type power connector for easy connection to wall block power supplies
• Tiny Machine Basic programming language for the SI51 programmed into the microcontroller
• EEPROM based AT89C4051 can be re-programmed using common Intel 8051/Atmel AT89Cxx51 software development tools and device programmer

Operating environment:
Temperature: 0-50 degrees Celsius (32-122 Fahrenheit)
Humidity: 30 to 80 percent, non-condensing

Logic level I/O signals (DI1, DI2, DI3, INT)-
(10K pull-up resistor to +5, 0.01uf capacitor to ground)
Output source current: 0.5 mA
Output sink current: 20 mA maximum each pin

Switch/contact closure signals (S1-S16)-
(270 ohm pull-up resistor through LED to +5, 0.1uf to ground)
Contact or external signal sink current required: 12 mA

To facilitate the connection of devices requiring power to the SI51, the +5 volt signal from the on-board regulator has been connected to pin 9 of the serial connector. This connection will not affect normal serial ports since +5 volts is within the range of allowable voltages on RS-232 input pins.

The following is a pin out of the serial port signals:

SI51 signal   -    TX   RX   -    GND  -    -    -    +5 OUT
pin           1    2    3    4    5    6    7    8    9
PC signal     DCD  RX   TX   DTR  GND  DSR  RTS  CTS  RI

It is possible to drive the contact closure inputs with devices that contain digital logic output circuitry, but this circuitry must be able to sink the required current. A number of driver chips, and many transistors have this ability, but some do not. The user is responsible for insuring that damage does not occur to the external device as a result of sinking the required current.

The limitations of the digital logic level signals are the same as those of the microcontroller chip installed. They can "sink" 20 milliamperes each with a total current of 80 milliamperes (steady state) for all signals. The addition of the 10K pullup resistors allows the signals to "source" 0.5 milliamperes each. For more information on the limitations of these signals, see the data sheet.

The +5 signal on the screw terminal connector is the same power supply that is used by the circuitry on the SI51, and can be used to power external devices. The current drawn from this signal should be limited to 100 milliamperes.