PBASIC Instruction Set

The following gives a complete list of PBASIC commands for both versions of the Stamp. It does not include arithmetic or logical operators. Many enhancements were made to the PBASIC language with the release of the BASIC Stamp II and thus some commands only exist on one version of the BASIC Stamp. For more detailed information on the differences between PBASIC1 and PBASIC2, download the BASIC Stamp I to BASIC Stamp II Conversion document.

Indicates instruction is only available on BASIC Stamp D and BS1-IC.
Indicates instruction is only available on BS2-IC.

BRANCHING
	IF . . .THEN	Compare and conditionally branch.
	BRANCH	Branch to address specified by offset.
	GOTO	Branch to address.
	GOSUB	Branch to subroutine at address.
	RETURN	Return from subroutine.
LOOPING
	FOR . . . NEXT	Establish a FOR - NEXT loop.
NUMERICS
	LET	Perform variable manipulation, such as A=5, B=A+2, etc. Possible operations are add, subtract, multiply, divide, max. limit, min. limit, and logical operations AND, OR, XOR, AND NOT, OR NOT, and XOR NOT.
	LOOKUP	Lookup data specified by offset and store in variable. This instruction provides a means to make a lookup table.
	LOOKDOWN	Find target's match number (0-N) and store in variable.
	RANDOM	Generate a pseudo-random number.
DIGITAL I/O
	INPUT	Make pin an input
	OUTPUT	Make pin an output
	REVERSE	If pin is an output, make it an input. If pin is an input, make it an output.
	LOW	Make pin output low.
	HIGH	Make pin output high.
	TOGGLE	Make pin an output and toggle state.
	PULSIN	Measure an input pulse.
	PULSOUT	Output a timed pulse by inverting a pin for some time.
	BUTTON	Debounce button, perform auto-repeat, and branch to address if button is in target state.
	SHIFTIN	Shift bits in from parallel-to-serial shift register.
	SHIFTOUT	Shift bits out to serial-to-parallel shift register.
	COUNT	Count cycles on a pin for a given amount of time (0 to 125 kHz, assuming 50/50 duty cycle).
	XOUT	Generate X-10 powerline control codes. For use with X-10 lamp and appliance control modules.
SERIAL I/O
	SERIN	Serial input with optional qualifiers and variables for storage of received data. On the Stamp D and BS1-IC, baud rates of 300, 600, 1200, and 2400 are possible. On the BS2-IC, any baud rate (up to 50k baud) is possible. Also, the BS2-IC has a serial input time-out function.
	SEROUT	Send data serially. On the Stamp D and BS1-IC, data is sent at 300, 600, 1200, or 2400 baud. On the BS2-IC, data is sent at any baud rate (up to 50k baud).
ANALOG I/O
	PWM	Output PWM, then return pin to input. This can be used to output analog voltages (0 to 5 V) using a capacitor and resistor.
	POT	Read a 5 to 50K potentiometer and scale result.
	RCTIME	Measure an RC charge/discharge time. Can be used to measure potentiometers (faster than POT on Stamp D and BS1-IC).
SOUND
	FREQOUT	Generate one or two sine waves of specified frequencies (each from 0 to 32767 Hz).
	DTMFOUT	Generate DTMF telephone tones.
	SOUND	Play notes. Note 0 is silence, notes 1 to 127 are ascending tones, and notes 128 to 255 are white noises.
EEPROM ACCESS
	DATA	Store data in EEPROM before downloading BASIC program (BS2-IC).
	EEPROM	Store data in EEPROM before downloading BASIC program (Stamp D and BS1-IC)
	READ	Read EEPROM byte into variable.
	WRITE	Write byte into EEPROM
TIME
	PAUSE	Pause execution for 0 to 65536 milliseconds.
POWER CONTROL
	NAP	Nap for a short period. Power consumption is reduced.
	SLEEP	Sleep for 1 to 65535 seconds. Power consumption is reduced to 20 µA (Stamp D and BS1-IC) or 50 µA (BS2-IC).
	END	Sleep until the power cycles or the PC connects. Power consumption is the same as SLEEP instruction.
PROGRAM DEBUGGING
	DEBUG	Sends variables to PC for viewing.