basic stamps

BASIC Stamps are small reprogrammable single board computers (SBC) that run Parallax BASIC (PBASIC) programs. They have fully programmable I/O pins that can be used to directly interface to TTL-level devices, such as buttons, LEDs, speakers, potentiometers, and shift registers. And with just a few extra components, these I/O pins can be connected to non-TTL devices, such as solenoids, relays, RS-232 networks, and other high current/voltage devices. Their low cost and simplicity make the Stamps perfect for many prototyping and control applications. It's suitable for electronics hobbyists as well as electronics professionals in many different areas.

General electronics
Home automation
Robotics
Mini PLC
Education
Prototyping
HAM related applications
Special effects in films
Industrial control
Geological instruments
Computer peripherals
Scale model hobbyists
Model train hobbyists

BASIC Stamps are available in various physical packages, but all versions have the same logical design, consisting of a 5-volt regulator, resonator, serial EEPROM, and PBASIC interpreter. A tokenized PBASIC program is stored in the nonvolatile serial EEPROM, which is read from and written to by the interpreter chip. This interpreter chip fetches the instructions one at a time and performs the appropriate operation on the I/O pins or internal structures within the interpreter. Because the PBASIC program is stored in an EEPROM, it may be programmed and reprogrammed almost endlessly, without the need to first erase the memory, as with many microcontrollers. To program BASIC Stamp, you just connect them to an IBM PC or compatible (parallel port for the BASIC Stamp I, and serial port for the BASIC Stamp II and IISX) and run our editor software to edit and download your program. (Parallax: Architecture of a BASIC Stamp)

The BASIC Stamp I connects to your PC's parallel port. You may purchase a cable or build your own:

The BASIC Stamp II and IISX connect to your PC's serial port. You may purchase a serial cable or again build your own. Serial port pins 6 (DSR) and 7 (RTS) may be connected for automatic port detection:

The BASIC Stamp is programmed with a DOS (BASIC Stamp I, II, and IISX) or Windows 95/98/NT4.0 (BASIC Stamp II and IISX) editor. Programs are written and downloaded to the BASIC Stamp in the editor. When the download is complete the program automatically runs in your BASIC Stamp. The editor is used to check your program syntax, display the BASIC Stamp's available memory resources, and to debug your program. By inserting a "debug" command in your program you can view variable values on your PC screen, or in a terminal program. All software is available for free download. (Parallax, Programming a BASIC Stamp from a PC)

BASIC Stamp Software
BASIC Stamp DOS and Windows editor software, StampPlot Lite and StampPlot Pro.

BASIC Stamp Documentation
BASIC Stamp manuals, application notes and Windows interface documentation. All documentation for modules and OEM versions.

BASIC Stamp Application Kit Documentation (includes source code)
Real-time clocks, digital thermometers, A/D converters, LED display drivers, EEPROM and modem interface documentation. Real-time clocks, digital thermometers, A/D converters, LED display drivers, EEPROM and modem interface documentation.

BASIC Stamp Accessories
Activity boards, Boe-Bot, GrowBot, infrared, stepper controllers, serial servo controllers, h-bridges, NTSC/pal character overlay, serial LCDs, Stache field programmer, etc.

Stamps in Class Curriculum
What's a Microcontroller?, Earth Measurements, Robotics!, Basic Analog and Digital, and Industrial Control curricula.

SX Keys and SX Chips
Software, documentation and sample source code for our SX-Key product line.

Basic Stamp FAQ by Al Williams- an excellent source of answers to all of your perplexing Stamp questions:

2.1 What's the best way to get started?
2.2 What do I need?
2.3 What can I use as a power supply?
2.4 How can I drive an LED?
2.5 How can I drive devices that require higher current (light, relay, motor, etc.)?
2.6 What's the best way to control the speed and direction of a motor?
2.7 How can the PC reset my Stamp?
2.8 Why can't I talk to the Stamp with my terminal software?
2.9 What are Pull-up and Pulldown Resistors?
2.10 How can I read a calculator-style keyboard?
2.11 Where can I find information on basic electronics?
2.12 Where can I find information about soldering?
2.13 Where can I find information about making PC boards?
2.14 My BS2 locks up and/or resets when I leave the programming cable attached to it. Why?
2.15 Can the Stamp do [fill in the blank] at the same time as [fill in the blank]?
2.16 How can I transmit data via radio?
2.17 Where can I get more powerful RF modules or modify the low-power devices to get more range?
2.18 Can I add more program storage to the Stamp?
2.19 Is it necessary to terminate Stamp pins?
2.20 How can I drive an LCD display?
2.21 Why is it that RS-232 is supposed to be limited to 50 feet? I've used it at longer distances with no trouble.
2.22 How can I count revolutions of a shaft?
2.23 How can I read the position of a shaft?
2.24 How can I connect an RS232 device?
2.25 How can I read logic signals greater than 5V?
2.26 How do I make my own PC boards?
2.27 The Stamp manual says its PWM command generates random pulses. Why?
2.28 Does the Stamp have hardware interrupts?
2.29 How do transistors work?
2.30 How do I select capacitors?
2.31 Who will make inexpensive PC boards for me?
2.32 Can you explain common synchronous protocols?
2.33 How can I convert a low-level sensor input to 0-5V?
2.34 What IR detectors are available?
2.35 Is there a Stamp library for EagleCad

L.O.S.A. (List of Stamp Applications) Contribution Form
The main purpose of this list is to get an idea of what other people are using their BASIC Stamps for and maybe get some inspiration or hints for your own projects. Some of the projects described in the list also have links to source code and schematics for download.

Circuit Cellar provides up to date information for engineers, www.circuitcellar.com for more information and additional articles.
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