We had a project that required connection to a digital micrometer with a data output jack. The idea was to connect a microcontroller to the micrometer, to read the measurements and make decisions based on the readings. The micrometers that we used are made by Mitutoyo, and have a funky 52 character data stream in reverse bit order. The microcontroller we chose is the Arduino, and we used a 4D systems uVGA-II to take serial output from the Arduino and display it on a VGA monitor. Parts available from Hacktronics
me if you want a kit.
Major Components: Mitutoyo 293-335 Coolant Proof LCD Micrometer, Friction Thimble, 0-1"/0-25.4mm Range, 0.001mm/0.00005" Graduation, +/-0.00005" Accuracy, SPC Output Mitutoyo 05CZA662, Digimatic Cable, 40", With Data Switch for Coolant Proof Micrometers µVGA-II(SGC) PICASO QVGA/VGA/WVGA Graphics Controller Arduino Mega or compatible Protoshield recommended
2 PN2222A transistors four 10k Ohm resistors 2x5 shrouded header
one momentary pushbutton
Step 1: Mitutoyo Cable Schematic
This is a diagram showing how the Mitutoyo cable is wired. There is a red "data" button on the micrometer end of the cable that we were not using in this application, so we decided to use it as a "menu" button.
Step 2: Connecting the cable to the Arduino
The Arduino connects to the Mitutoyo cable with a few components. A 2x5 shrouded header that mates to the female plug on the cable, a PN2222A transistor, and two 10k Ohm resistors. One resistor is used with the PN2222A to protect the micrometer (or caliper) from excessive voltage, the other to bias the "menu" button to +5vdc.