The BASIC Stamp is a

microcontroller A microcontroller (MCU for ''microcontroller unit'', often also MC, UC, or μC) is a small computer on a single VLSI integrated circuit (IC) chip. A microcontroller contains one or more CPUs ( processor cores) along with memory and programmabl ...

with a small, specialized

BASIC interpreter A BASIC interpreter is an interpreter that enables users to enter and run programs in the BASIC language and was, for the first part of the microcomputer era, the default application that computers would launch. Users were expected to use the BAS ...

(

PBASIC PBASIC is a microcontroller-based version of BASIC created by Parallax, Inc. in 1992. PBASIC was created to bring ease of use to the microcontroller and embedded processor world. It is used for writing code for the BASIC Stamp microcontrollers. A ...

) built into ROM. It is made by Parallax, Inc. and has been popular with electronics hobbyists since the early 1990s.

Technical specifications

Although the BASIC Stamp 2 has the form of a 24 pin DIP

chip Chromatin immunoprecipitation (ChIP) is a type of immunoprecipitation experimental technique used to investigate the interaction between proteins and DNA in the cell. It aims to determine whether specific proteins are associated with specific genom ...

, it is in fact a small

printed circuit board A printed circuit board (PCB; also printed wiring board or PWB) is a medium used in electrical and electronic engineering to connect electronic components to one another in a controlled manner. It takes the form of a laminated sandwich str ...

(PCB) that contains the essential elements of a microprocessor system: * A Microcontroller containing the

CPU A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, a ...

, a built in ROM containing the BASIC interpreter, and various peripherals * 2kB of

i²C I2C (Inter-Integrated Circuit, ), alternatively known as I2C or IIC, is a synchronous, multi-controller/multi-target (master/slave), packet switched, single-ended, serial communication bus invented in 1982 by Philips Semiconductors. It is wid ...

EEPROM EEPROM (also called E2PROM) stands for electrically erasable programmable read-only memory and is a type of non-volatile memory used in computers, usually integrated in microcontrollers such as smart cards and remote keyless systems, or ...

memory. * A clock, in the form of a

ceramic resonator A Ceramic Resonator is an electronic component consisting of a piece of a piezoelectric ceramic material with two or more metal electrodes attached. When connected in an electronic oscillator circuit, resonant mechanical vibrations in the device g ...

Voltage regulator A voltage regulator is a system designed to automatically maintain a constant voltage. A voltage regulator may use a simple feed-forward design or may include negative feedback. It may use an electromechanical mechanism, or electronic components ...

* External

input/output In computing, input/output (I/O, or informally io or IO) is the communication between an information processing system, such as a computer, and the outside world, possibly a human or another information processing system. Inputs are the signals ...

The end result is that a hobbyist can connect a 9 V battery to a BASIC Stamp and have a complete system. A serial connection to a

personal computer A personal computer (PC) is a multi-purpose microcomputer whose size, capabilities, and price make it feasible for individual use. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or te ...

allows the programmer to download software to the BASIC Stamp, which is stored in the onboard

non-volatile memory Non-volatile memory (NVM) or non-volatile storage is a type of computer memory that can retain stored information even after power is removed. In contrast, volatile memory needs constant power in order to retain data. Non-volatile memory typi ...

device: it remains programmed until it is erased or reprogrammed, even when the power of the stamp is removed. If the power is reconnected the stamp immediately starts executing the program in slot 0 (of 8, numbered 0..7).

Programming

The BASIC Stamp is programmed in a variant of the

BASIC BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College ...

language, called PBASIC. PBASIC incorporates common microcontroller functions, including PWM, serial communications,

I²C I2C (Inter-Integrated Circuit, ), alternatively known as I2C or IIC, is a synchronous, multi-controller/multi-target (master/slave), packet switched, single-ended, serial communication bus invented in 1982 by Philips Semiconductors. It is wid ...

and

1-Wire 1-Wire is a device communications bus system designed by Dallas Semiconductor Corp. that provides low-speed (16.3 kbit/s) data, signaling, and power over a single conductor. 1-Wire is similar in concept to I²C, but with lower data rates and ...

communications, communications with common LCD driver circuits, hobby servo pulse trains, pseudo-sine wave frequencies, and the ability to time an

RC circuit A resistor–capacitor circuit (RC circuit), or RC filter or RC network, is an electric circuit composed of resistors and capacitors. It may be driven by a voltage or current source and these will produce different responses. A first order RC ...

which may be used to detect an analog value. Once a program has been written in the 'Stamp Editor', an

integrated development environment An integrated development environment (IDE) is a software application that provides comprehensive facilities to computer programmers for software development. An IDE normally consists of at least a source code editor, build automation tools ...

(IDE) in Windows, the

syntax In linguistics, syntax () is the study of how words and morphemes combine to form larger units such as phrases and sentences. Central concerns of syntax include word order, grammatical relations, hierarchical sentence structure ( constituenc ...

can be checked,

tokenized In computer science, lexical analysis, lexing or tokenization is the process of converting a sequence of characters (such as in a computer program or web page) into a sequence of ''lexical tokens'' ( strings with an assigned and thus identified ...

and sent to the chip through a serial/ USB Mini-B cable, where it will run.

Versions

There are currently four variants of the interpreter: # (1992) BASIC Stamp 1 (BS1) # (1995) BASIC Stamp 2 (BS2), with six sub-variants: ## BS2e ## BS2sx ## BS2p24 ## BS2p40 ## BS2pe ## BS2px # (2002) Javelin Stamp # (2006) Propeller\Spin Stamp The BS2 sub-variants feature more memory, higher execution speed, additional specialized PBASIC commands, extra I/O pins, etc., in comparison to the original BS2 model. While the BS1 and BS2 use a PIC, the remaining BASIC Stamp 2 variants use a

Parallax SX Parallax SX is a discontinued line of microcontrollers that was marketed by Parallax, from a design by Ubicom. Designed to be architecturally similar to the PIC microcontrollers used in the original versions of the BASIC Stamp, SX microcontrollers ...

processor. The third variant is the Javelin Stamp. This module uses a subset of

Sun Microsystems Sun Microsystems, Inc. (Sun for short) was an American technology company that sold computers, computer components, software, and information technology services and created the Java programming language, the Solaris operating system, ZFS, t ...

Java Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's mo ...

programming language instead of Parallax's PBASIC. It does not include any networking facilities. The fourth variant is the Spin Stamp. The module is based on the

Parallax Propeller The Parallax P8X32A Propeller is a multi-core processor parallel computer architecture microcontroller chip with eight 32-bit reduced instruction set computer (RISC) central processing unit (CPU) cores. Introduced in 2006, it is designed and sold ...

and therefore uses the SPIN programming language instead of PBASIC. A number of companies now make "clones" of the BASIC Stamp with additional features, such as faster execution,

analog-to-digital converter In electronics, an analog-to-digital converter (ADC, A/D, or A-to-D) is a system that converts an analog signal, such as a sound picked up by a microphone or light entering a digital camera, into a digital signal. An ADC may also provide ...

s and hardware-based PWM which can run in the background. The Parallax Propeller is gradually accumulating software libraries which give it functionality similar to the BASIC Stamp; however, there is no uniform list of which PBASIC facilities now have Spin equivalents.

References

External links

"Comparing PBASIC 2.5 control structures to the old PBASIC"
– By Tracy Allen, EME Systems, 2003
Parallax Forums
– Discussion Forum
Parallax, Inc.
– Corporate website, home of the Basic Stamp and Basic Stamp 2

– By Andy Kaiser {{DEFAULTSORT:Basic Stamp Microcontrollers Parallax, Inc. products BASIC interpreters

Technical specifications

Programming

Versions

See also

References

External links