28023 Parallax Inc, 28023 Datasheet - Page 6

• Manufacturer Part Number: 28023
• Description: CONTROLLER 16SERVO MOTOR CONTROL
• Manufacturer: Parallax Inc

Specifications of 28023

• Lead Free Status: Contains lead
• Main Purpose: Power Management, Motor Control
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: BASIC Stamp® or Javelin Modules
• Primary Attributes: Servo Controller
• Secondary Attributes: 16 channels
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 28023PAR

250 up to 260 (or so) to prevent the servo from straining itself.
Similarly, if your servo strains when commanded to go to position
1250, you should decrease the 1250 to 1240 or so to prevent the
servo from straining itself.
RSP Command – Report the Position of a Servo Channel
Syntax: “!SCRSP” x $0D
Reply: x y z(where x is the channel number, and z:y is the value reported)
Sometimes it is necessary to know the current servo position. The RSP command returns the value of
the specified servo channel. If the servo is still moving as a result of a ramp command, the position may
still be read. The following code snippet demonstrates how to use this command.
'{$PBASIC 2.5}
ch
pw
ra
x
Buff
Sdat
baud
Init:
DO
LOOP
WRservo:
Within the DO-LOOP, this program sets the pulse width (pw) to one extreme or the other and writes this
value to the PSC. The ramp value (ra) was set to give the program time to poll the servo position several
times. Within the WRservo subroutine, the new pw is sent, and the position is polled five times, once
each second. A DEBUG command is used to format the reply and post it to a window for your review.
6
ra =
pw = 1240: GOSUB WRservo
pw =
SEROUT Sdat, Baud+$8000,["!SC", ch, ra, pw.LOWBYTE, pw.HIGHBYTE, CR]
FOR x = 0 TO 4
NEXT
RETURN
PAUSE 1000
SEROUT Sdat, Baud+$8000, ["!SCRSP", ch, CR]
SERIN
DEBUG "Servo ", DEC buff(0), "
VAR Byte
VAR Word
VAR Byte
VAR Byte
VAR Byte(3)
CON 15
CON 396
240: GOSUB WRservo
15: ch = 0
Sdat, Baud, 1000, Init,[STR Buff\3]
Parallax, Inc. • Parallax Servo Controller – Rev B ver 2.4 (#29023) • 1/2005
", HEX2 buff(1), " :", HEX2 buff(2), CR