INSTRUCTION MANUAL

Page 52
Decoder MX620 - MX622, MX630 - MX632 Sound Decoder MX640 - MX648
Connecting servo and
SmartServo motors:
2 servo control outputs are available on the
MX620, MX630. MX632 and MX640 decoders
for the control of commercially
available servo motors or SmartServo RC-
1 (Manufactured by TOKO Corp. Japan).
The servo solder pads or pins on the 21-
pin or PluX connector can also be used alternatively
for SUSI or as logic level outputs.
The SUSI and logic level functions are not
available if the servo mode is activated
(through CV’s #181 and 182, see below);
this is also true for the function outputs
FO5 and FO6 on the MX632.
The models MX632W and MX632WD contain
a 5V power supply to power servos
directly; the 5V supply on the MX640 is
limited to 200mA.
For other decoder types, the 5V must be
supplied by an external voltage regulator
such as the readily available LM7805;
connected as shown in the drawing.
The outputs can be activated for servo
control duty with CV’s #181 and CV #182
(the value in each must be different than
0).
With the help of CV #181 and #182, the
servo functions can be mapped to various
function keys (plus direction) and selected
for control with either one or two function
keys.
CV’s #161 to #169 define the servos end
positions and rotating speed, see CV table.
CV #161 also defines the appropriate servo
protocol. “Normal” for most servos is
positive pulses (which is also the default
setting); furthermore a selection can be
made whether the servo is powered only
while it is being moved or remains powered
at all times. The latter should only be
used if the servo position could change by
outside mechanical influences.
Connecting MX640 and MX642 to servo and SmartServo motors:
Two servo connections are provided on the MX640 for commercially available servos and SmartServo
RC-1 (Manufacturer: TOKI Corp., Japan). These are normally the SUSI outputs but can also be
used as servo outputs instead. The connections are in the form of either solder pads or part of the
21-pin socket, depending on the decoder type. Each output can be connected directly with a servo
input.
“Energy-saving” servos (max. 200mA) can be powered directly by the MX640!
For servos with higher energy consumptions, the 5V operating voltage must be supplied by an external
voltage regulator such as the readily available LM7805 as shown in the drawing.
The outputs can be activated for servo control duty with CV’s #181 and CV #182 (the value in each
must be different than 0). With the help of CV #181 and #182, the servo functions can be mapped to
various function keys (and direction) and selected for control with either one or two function keys.
CV’s #161 to #169 define the servos end positions and rotating speed, see CV table.
The appropriate servo protocol can be selected with CV #161. “Normal” for most servos is positive
pulses (which is also the default setting); furthermore a selection can be made whether the servo is
powered only while it is being moved or remains powered at all times. The latter should only be used
if the servo position could change by outside mechanical influences. For the SmartServo: Bit 1 of
CV #161 must always be set, that is CV #161 = 2!