28138 Parallax Inc, 28138 Datasheet - Page 7

• Manufacturer Part Number: 28138
• Description: BOARD DEV PROFESSIONAL
• Manufacturer: Parallax Inc
• Series: BASIC Stamp®r
• Type: MCUr

Specifications of 28138

• Contents: Development Board
• Processor To Be Evaluated: SX28AC/DP
• Interface Type: RS-232
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: BASIC Stamp®, Javelin Stamp, and SX28AC/DP
• For Use With: 900-00014 - SERVO CONTROLLER PICO GWS130-28029 - KIT PARTS SMART SENSORS27957 - MANUAL USER FOR JAVELIN STAMP28138 - BOARD DEV PROFESSIONAL805-00006 - CABLE USB A TO MINI B27937 - MEMORY STICK DATALOGGER658-1021-5 - PROGRAMMER TEACLIPPER/STAMP30010 - BASIC STAMP LOGIC ANALYZER27220 - BOOK STAMPWORKS27330 - PROGRAMMER STACHE BASIC STAMP27218 - MANUAL BASIC STAMP VER 2.0
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Parallel LCD Connector (X2)
Box header X1 provides the connection for an HD44780-compatible LCD module. Connection to the
circuit is made via X2. Note that X2 is configured such that the LCD data buss (DB0 – DB7) is split, and
the E, RW, and RS lines have dual connections as shown in the diagram below.
This configuration allows both 4- and 8-bit LCD applications to be developed. The potentiometer located
near X1 is used to adjust LCD display contrast.
Servo Headers (X4)
Headers X4 may be used to connect standard hobby servos to the PDB. Devices with the same pin
configuration (Signal / Vdd / Vss) may also be connected to these headers. Compatible devices include
the Parallax serial LCD module and Ping))) ultrasonic rangefinder.
10 kΩ Potentiometer (X5 and X6)
Two 10 kΩ potentiometers are provided via X5 and X6. A 220 Ω series resistor is placed inline with the
wiper connection to prevent an I/O pin from being connected directly to Vdd or Vss.
© Parallax, Inc. • Professional Development Board (#28138) • 06/2005
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