WARNINGS:
        Be very careful about applying power to the motor control chip.  Reversed
        power *WILL* destroy the chip.  The chip is soldered in place to take
        advantage of the ground plane heat sink and is difficult to replace.

        This board contains static sensitive devices.  Observe normal precautions.

        This board has *no* polarity reversal protection, nor does it have any input
        protection for the micro-processor.  Please be careful how you connect it with
        your R/C gear or micro processor board.

        There are holes on the board for an 78l05 voltage regulator.  This part is
        not supplied.  Power can be taken from your R/C receiver via the input pins
        using standard R/C cables.  If you are using a relatively low motor voltage,
        less than 10v, then it is reasonable to put in a voltage regulator and run your
        R/C radio from the controller board.  This is not practical for higher supply
        voltages as the regulator will overheat.

Specifications:
        Maximum current draw per channel: 1.1A (TI 754410 dual H-Bridge)
        Maximum supply voltage: 35v
        Switching frequency: 1.0-1.7 khz (high vs low range select)
        R/C Pulse width resolution: 4 uS (samples at 250khz)
        Number of steps: 75 (low range) 125 (high range)

The jumpers:

Brk:    Selected is BRAKE, open is COAST.  Brake vs Coast when zero drive is detected
        (1.5ms pulse +/- deadband)

Rng:    Range: Selects .8 ms or 1.0 ms range of input pulses. The narrower
        range is more appropriate for off-the-shelf R/C gear where you don't have
        control over the pulse width range.  The wider range is for computer control
        (e.g. basic stamp) which have arbitrary wider ranges.
        
DB1:    Deadband select.  This sets a small deadband around which the Zero position of
        the input pulse is compared.  Jumpered is zero deadband, open has a 12 uS dead-
        band.  The latter is appropriate for R/C gear which has mechanical slop and
        doesn't always put out a precise 1.5ms pulse when centered.  Note: the resolution
        of the pulse detection logic is 4 uS, so there is a natural +/- 2 uS dead band
        in the logic.

DB0:    Re-named to "Mix", when selected, puts converter into "Mixed" mode where the A
        channel determines the output level for both A and B, and the B channel
        differentially modifies the output.  This is for single joystick motion control.

Input connector:

        Looking towards the input connectors, the wiring is from left to right: BLACK,
        RED, WHITE.  That is, the left most pin is GND.

Output Connector:

        Looking towards the output connectors, the two active pins are on the LEFT.  If
        connecting a hacked servo, the wires would be, from left to right: BLACK, RED, WHITE.

        
        

