Servo Pulsout

Newzed

With a BS2 I would pulsout 750 to center·a servo.· This is acutally 1500us.· If I want to use a BS2P24 do I pulsout 1500/.8 = 1875us to
achieve the same result?

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Sid Weaver
New Combo LCD Backpack

http://hometown.aol.com/newzed/index.html
·

allanlane5

Umm, the Basic Stamp 2 Programming Manual, under the PULSOUT entry, says the PULSOUT 'tick' size for the BS2p is 1.18 uSec. The BS2sx uses 0.8 usec. Thus your math is good for the BS2sx, *not* the BS2p.

For the BS2p, you would need 1.5 mSec/1.18 uSec == 1271 'ticks'.

(To check, 1271 * 1.18 uSec == 1.49978 mSec. *Should* be close enough.)

Newzed

Allan, the current Help file for the Editor says .8 for the BS2P and the BS2SX.· I wonder which is right?

One other question:

I just want to make sure of something before I wrap up this big PC board.
If I read, say GP0, and get %10000001, the first 1(msb) is GP0.7 and the last 1 (lsb) is GP0.0.· Correct?



Sid

allanlane5

Yes, the MSBit (Most Significant Bit) is considered Bit 7. The LSB is Bit 0. This is done by convention, and that *is* the convention for the BS2 (and the PIC it is based on). Good question.

For the pulse width -- the fastest way to know for sure is to try it. Just checked the on-line help, and darn if you arn't correct. So now we have two standards which each say something different. Help me, Mr. Wizard (Jon)!

Jon Williams

The current help file has a conditional compilation example for PULSOUT that should help you with different BASIC Stamp modules.

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Jon Williams
Applications Engineer, Parallax
Dallas Office

dandreae

Hello,

Actually the 0.8uS is correct for the BS2sx and BS2p.

Dave