Product Documentation

if new speed < current speed
steps = (current speed - new speed) / acceleration register
time = steps * 25ms
For example :
Acceleration
register
Time/step Current speed New speed Steps Acceleration time
1 25ms 0 255 255 6.375s
2 25ms 127 255 64 1.6s
3 25ms 80 0 27 0.675s
5 (default) 25ms 0 255 51 1.275s
10 25ms 255 0 26 0.65s
Mode
The mode command changes the way the speed/turn values are used. The options being:
0, (Default Setting) If a value of 0 is written then the speed registers is literal speeds in the range of 0 (Full Reverse) 128 (Stop)
255 (Full Forward).
1, Mode 1 is similar to Mode 0, except that the speed values are interpreted as signed values. The range being -128 (Full Reverse)
0 (Stop) 127 (Full Forward).
2, Writing a value of 2 to the mode will make speed1 control both motors speed, and speed2 becomes the turn value.
Data is in the range of 0 (Full Reverse) 128 (Stop) 255 (Full Forward).
3, Mode 3 is similar to Mode 2, except that the speed values are interpreted as signed values.
Data is in the range of -128 (Full Reverse) 0 (Stop) 127 (Full Forward)
GET VI or SET VI
This command instructs the MD25 to send the battery volts reading (125 = 12.5v), then the current being drawn by motor 1 (roughly
1 count per 100mA) and finally the current being drawn by motor 2.
MD25 Serial Documentation http://www.robot-electronics.co.uk/htm/md25ser.htm
3 of 3 2013-05-31 10:27