Programming the Hi-Tec HS 805BB with the BS2

Help & Support Robot Parts
1

I recently purchased several Mega Servo’s and am trying to get the BS2SX to run them.

The servo is the HS - 805BB and its a standard 180 degree servo but
Mega Quarter scale

The literature points to 1500us as the neutral value which i have tested with Pulsout 4, 1500 and it works. I have not had success getting a full movement clockwise then counterclockwise.

This is the code I have been running;
My goal was to get it to turn to its max in one direction, then come back to its max in the other direction.

If anyone has a solution it would be appreciated!

x var word

Main:
For x = 1 to 10
Pulsout 4, 1000
Pause 20
Next
Pause 1000
For x = 1 to 10
Pulsout 4, 2000
Pause 20
End
Pause 20

2

You don’t need the pause 1000. It will mess up the pulse generation. :unamused: I also made the program loop. The resolution for the BS2SX is 0.8uS not 1uS. You want these values instead.

750uS = 937
1000uS = 1250
1500uS = 1875
2000uS = 2500
2250uS = 2812

[code]x var byte

Main:
For x = 1 to 100
Pulsout 4, 1250
Pause 20
Next
For x = 1 to 100
Pulsout 4, 2500
Pause 20
Next
goto Main[/code]

3

Your the man RD! http://www.clipartof.com/images/emoticons/xsmall2/2403_worshipper.gif

4

The first thing I did with my BS manual was to write all these stupid pulsout variants in it so I could keep track of them! hehe

5

Jim, you gave me some good info and I made the changes with the values you suggested.

I currently can get the servo to run from centered to left but no values I have tried, will run the servo right.

I am currently running the code shown below. I have run every value in 100 increments up to 5000 and it won’t go right …only left

With parallax servos the BS2SX will run the servos from a 750 center
850 in one direction and 650 in the other.

I assume that the Hi-tec Servos should work in a similar fashion? (with numerical value changes due to timing)

Am I missing something here?

I tried each of the values below

750uS = 937
1000uS = 1250
1500uS = 1875
2000uS = 2500
2250uS = 2812

x VAR Byte

Main:
FOR x = 1 TO 100
PULSOUT 4, 2500
PAUSE 20
NEXT
GOTO Main

6

I had this problem and it was due to a bad servo. Can you try another servo? if this happens to all your servos then It might be due to a weak power supply. A good strong power supply that cap provide 2 amps should be used.

7

Yeah! on a BS2, not on a BS2SX…

Probably…

The parallax and hitec servos respond to the same pulse range. :unamused:

Pulsout for a stock BS2 has a resolution of 2uS. So pulsout of 750 produces a 1500uS pulse! This will center a servo.

Pulsout for a BS2SX has a resolution of 0.8uS. So pulsout of 750 produces a 600uS pulse! A 600uS pulse will command the HS-805 to its far left position.

The math is correct! You must have another sort of issue…

Could be your servos is drawing too much power causing your stamp to reset.

Could be your servo is broken.

Could be you have a BS2 not a an SX.

Could be dark eerie cloud has converged over your lab causing time, space and basic physics to not behave in the correct and accepted manner that we all have come to rely on.

8

I had Problem #4 before, and to fix it, I had to wear aluminum foil on my head and take a 9v battery and touch it to my toung, then the cloud went away…

9

I usually have to shape the foil into a pyramid shape for the best performance. What’s the frequency Kenneth?