27906 Parallax Inc, 27906 Datasheet - Page 8

• Manufacturer Part Number: 27906
• Description: BASIC STAMP ACT BOARD NO PWR
• Manufacturer: Parallax Inc

Specifications of 27906

• Module/board Type: Activity Board
• For Use With/related Products: BASIC Stamp®
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

CLRP – Clear Position
Description: This command resets the current position, end point, and set point back to zero. This
Copyright © Parallax Inc.
Command #:
5
+200 positions followed by another command to travel -130 positions is equivalent to a
single command to travel +70 positions.
It is possible to send a TRVL command which requires the wheel to reverse its current
direction of travel in order to seek the end point.
decelerate at the speed ramp rate in its current direction before re-accelerating in the
opposite direction. This effect is also seen when a TRVL command moves the end point to
a position which is still in the same direction of travel but is too close to be reached by
decelerating at the speed ramp rate. Rather than stopping abruptly or decelerating faster
than the speed ramp rate will allow, the wheel will decelerate smoothly past the end point
to a stop before re-accelerating in the opposite direction to the current end point.
Sending a command to travel 0 positions is a special case used to bring the wheel to a
smooth stop when traveling. The current speed is decelerated at the speed ramp rate and
the end point is advanced to the exact location where the speed will reach zero. Note that
this special case is not considered accumulative and will override the previously remaining
distance to travel.
expected.
To immediately stop the wheel (without decelerating at the speed ramp rate) the user
should send a Clear Position (see CLRP command) which effectively halts the wheel at its
current position.
Transmit Data Format
effectively halts the wheel at its current position. The current position becomes the new
starting point for position measurement and motion; and consequentially clears any TRVL
commands which may be in progress.
This command can also be used as a means to “soft-reset” a Position Controller. For
example, if the main microcontroller is reset while in the middle of sending a TRVL
command, any data received after that will be interpreted as valid data, causing the wheel
to begin traveling to an unpredictable location. By sending the CLRP command three
times in a row to all present devices, it is ensured that any position advancement will be
cleared; however all configuration data will remain unchanged. To completely reset a
Position Controller to default including configuration data, it is recommended to cycle
power. This is considered a “hard-reset”.
[Command:Address]
Hex Value:
0x28
However, TRVL commands sent after this will be accumulative as
Position Controller Kit (#27906)
Binary Value:
00101 000
Receive Data Format
Command Category/Type:
When this occurs, the wheel will
Action
N/A
v1.1 3/22/2010 Page 8 of 13
Single, All