Continuous rotation servo v2.0

BASIC Stamp

Programming Examples

PBASIC has a PULSOUT command that sets the I/O

to an output and sends a pulse of the specified

Duration

. Since the servo needs this pulse refreshed every 20 ms for continuous operation, the PULSOUT

command is put in a counted FOR…NEXT loop to sustain continuous operation for the specified number

of cycles.

PULSOUT

Duration

Different BASIC Stamp modules use different units for the PULSOUT command's

Duration

argument.

When adapting BS2 code to another BASIC Stamp model, you may need to make adjustments. The table

below lists the PULSOUT ranges for each BASIC Stamp microcontroller. See the BASIC Stamp Manual or

BASIC Stamp Editor Help for more information.

BASIC Stamp Module 1.3 ms 1.5 ms 1.7 ms

BS1

100 150 200

BS2, BS2e, BS2pe

500 750 1000

BS2sx, BS2px, BS2p24/40

1250 1875 2500

The example shown below for a BASIC Stamp 2 causes a servo connected to BASIC Stamp 1/0 pin 12 to

first rotate full-speed clockwise for about 5 seconds, hold still for about 5 seconds, then rotate

counterclockwise for 5 seconds.

' {$STAMP BS2}

' {$PBASIC 2.5}

counter VAR Word

FOR counter = 1 TO 100 ' Rotate clockwise for ~5 seconds

PULSOUT 12, 850

PAUSE 20

FOR counter = 1 TO 100 ' Hold still for ~5 seconds

PULSOUT 12, 750

PAUSE 20

FOR counter = 1 TO 100 ' Rotate counterclockwise for ~5 seconds

PULSOUT 12, 650

PAUSE 20

For more examples with the BASIC Stamp 2, including 2-wheeled robot maneuvers and ramping, see

"Robotics with the Boe-Bot" Chapter 4, available for free download from the 28132 product page at