BASIC Stamp - AbsoluteAstronomy.com

The BASIC Stamp is a microcontroller

Microcontroller

A microcontroller is a small computer on a single integrated circuit containing a processor core, memory, and programmable input/output peripherals. Program memory in the form of NOR flash or OTP ROM is also often included on chip, as well as a typically small amount of RAM...

with a small, specialized BASIC interpreter

Interpreter (computing)

In computer science, an interpreter normally means a computer program that executes, i.e. performs, instructions written in a programming language...

(PBASIC

PBASIC

PBASIC is a microcontroller based version of BASIC created by Parallax, Inc. The language was created to bring ease of use to the microcontroller and embedded processor world. PBASIC is used for writing code for the BASIC Stamp microcontrollers. After the code is written it is tokenized and...

) built into ROM

Read-only memory

Read-only memory is a class of storage medium used in computers and other electronic devices. Data stored in ROM cannot be modified, or can be modified only slowly or with difficulty, so it is mainly used to distribute firmware .In its strictest sense, ROM refers only...

. It is made by Parallax, Inc.

Parallax, Inc. (company)

Parallax Inc. is a privately held company in Rocklin, California. Parallax Inc. designs, manufactures, and sells BASIC Stamp microcontrollers, Propeller microcontrollers, microcontroller accessories Parallax Inc. is a privately held company in Rocklin, California. Parallax Inc. designs,...

and has been popular with electronics hobbyists since the early 1990s because of its low threshold of learning and ease of use due to its simple to understand BASIC language and excellent documentation.

Technical specifications

Although the BASIC Stamp has the form of a DIP

Dual in-line package

In microelectronics, a dual in-line package is an electronic device package with a rectangular housing and two parallel rows of electrical connecting pins. The package may be through-hole mounted to a printed circuit board or inserted in a socket.A DIP is usually referred to as a DIPn, where n is...

chip

Integrated circuit

An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

, it is in fact a small Printed Circuit Board

Printed circuit board

A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate. It is also referred to as printed wiring board or etched wiring...

that contains the essential elements of a microprocessor system:

A Microcontroller containing the CPU, a built in ROM containing the BASIC interpreter, and various peripherals
Memory (an i²C
I²C
I²C is a multi-master serial single-ended computer bus invented by Philips that is used to attach low-speed peripherals to a motherboard, embedded system, cellphone, or other electronic device. Since the mid 1990s, several competitors I²C ("i-squared cee" or "i-two cee"; Inter-Integrated Circuit;...

EEPROM
EEPROM
EEPROM stands for Electrically Erasable Programmable Read-Only Memory and is a type of non-volatile memory used in computers and other electronic devices to store small amounts of data that must be saved when power is removed, e.g., calibration...

)
A clock, usually in the form of a ceramic resonator
Ceramic resonator
A ceramic resonator is an electronic component that when combined with other appropriate components, can produce oscillations at a specific frequency...
A power supply
External input and output

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

Personal computer

A personal computer is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator...

allows the programmer to download software to the BASIC Stamp, which is stored in the onboard non-volatile memory

Non-volatile memory

Non-volatile memory, nonvolatile memory, NVM or non-volatile storage, in the most basic sense, is computer memory that can retain the stored information even when not powered. Examples of non-volatile memory include read-only memory, flash memory, ferroelectric RAM, most types of magnetic computer...

device: it remains programmed until it is erased or reprogrammed, even when the power is removed.

Programming

The BASIC Stamp is programmed in a variant of the BASIC

BASIC

BASIC is a family of general-purpose, high-level programming languages whose design philosophy emphasizes ease of use - the name is an acronym from Beginner's All-purpose Symbolic Instruction Code....

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

Pulse-width modulation

Pulse-width modulation , or pulse-duration modulation , is a commonly used technique for controlling power to inertial electrical devices, made practical by modern electronic power switches....

, serial communications, I²C

I²C

I²C is a multi-master serial single-ended computer bus invented by Philips that is used to attach low-speed peripherals to a motherboard, embedded system, cellphone, or other electronic device. Since the mid 1990s, several competitors I²C ("i-squared cee" or "i-two cee"; Inter-Integrated Circuit;...

and 1-Wire

1-Wire

1-Wire is a device communications bus system designed by Dallas Semiconductor Corp. that provides low-speed data, signaling, and power over a single signal. 1-Wire is similar in concept to I²C, but with lower data rates and longer range. It is typically used to communicate with small inexpensive...

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

RC circuit

A resistor–capacitor circuit ', or RC filter or RC network, is an electric circuit composed of resistors and capacitors driven by a voltage or current source...

which may be used to detect an analog value.

Once the program has been written, it is tokenized

Lexical analysis

In computer science, lexical analysis is the process of converting a sequence of characters into a sequence of tokens. A program or function which performs lexical analysis is called a lexical analyzer, lexer or scanner...

and sent to the chip through a serial cable.

Versions

There are currently four variants of the interpreter:

BASIC Stamp 1 (BS1),
BASIC Stamp 2 (BS2), with six sub-variants:
1. BS2e
2. BS2sx
3. BS2p24
4. BS2p40
5. BS2pe
6. BS2px
Javelin Stamp
Spin Stamp.

The BS2 sub-variants feature more memory, faster 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

The Parallax SX line of microcontrollers were formerly made by Ubicom, who was originally Scenix, hence the SX- prefix. The SX dies are still manufactured by Ubicom, who sends them to Parallax for packaging...

processor.

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

Sun Microsystems

Sun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...

' Java

Java (programming language)

Java is a programming language originally developed by James Gosling at Sun Microsystems and released in 1995 as a core component of Sun Microsystems' Java platform. The language derives much of its syntax from C and C++ but has a simpler object model and fewer low-level facilities...

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

Parallax Propeller

The Parallax P8X32A Propeller chip, introduced in 2006, is a multi-core architecture parallel microcontroller with eight 32-bit RISC CPU cores....

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

Analog-to-digital converter

An analog-to-digital converter is a device that converts a continuous quantity to a discrete time digital representation. An ADC may also provide an isolated measurement...

s and hardware-based PWM which can run in the background.

The Parallax Propeller is gradually accumulating software libraries which give it similar functionality to the BASIC Stamp, however there is no uniform list of which PBASIC facilities now have Spin equivalents.

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
"Independent review of the Scribbler Robot, a programmable intelligent robot utilizing the BASIC Stamp 2 Microcontroller" – By Andy Kaiser

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.

Technical specifications

Programming

Versions

See also

External links