Micron MR603a User manual

MR603a Bottom
MR603a Top
Uplands House, Castle Howard Road, Malton YO17 6NJ
www.micronradiocontrol.co.uk
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Micron MR603a 2.4GHz DSM2/DSMX Receiver
This document is regular updated and the most recent version may be found online at
http://micronrc.uk/mr603a where you will be able to view larger versions of the images.
The MR603 receiver is designed for use in
larger scale model rail locomotives and road
vehicles. It provides a 3A reversible ESC for
brushed motors and 10 auxiliary outputs for
lighting, sound triggers, couplers, etc. It
operates on 2.4GHz and is compatible with
any Spektrum DSM2 or DSMX transmitter
including all of the Micron model rail transmitters. The voltage range is 4.5V to 20V.
MR603 requires binding with your transmitter before use. If purchased with a transmitter, it will be
already bound to that transmitter. Once bound, the transmitter should be switched on before the
MR603. If the transmitter is not switched on, MR603 will automatically enter bind mode 10 seconds
after switch on; it may also be configured to bind only manually using pads P5 and P6.
The MR603 free-air range, when used with a Micron low-power transmitter, is 50m-60m and
approximately 200m when used with a full-power (100mW) transmitter. This range will be reduced
indoors due to absorption by furniture / fittings and reflections from metal surfaces. Range is also
reduced if the receiver aerial is in a metal enclosure. Ideally, the aerial should be placed outside the
vehicle body and clear of any metal. The active tip of the extended aerial needs to 'see' the transmitter
so should be placed through a hole in the vehicle body - e.g. into the cab space. The MR603 aerial
should not be cut short or made longer as this will affect operation of the receiver. It is important to
perform a range check after installation to ensure you have full control of your loco/vehicle at all
positions around the layout.
Features
Compatible with all DSM2 and DSMX transmitters with up to 10 R/C channels, both Micron model
rail and aero model stick type transmitters.
4.5V to 10V working voltage range.
10 auxiliary outputs: 4 x F which are normally open switches capable of passing up to 2A; and 6 x
P which are 0V/3.3V logic outputs capable of supplying up to 20mA each. P outputs may also be
configured to drive servos.
Supports the Selecta feature for compatibility with multi-loco transmitters, MR603 must be re-
bound to change Selecta switch position.
The default configuration provides auto-switched front and rear LED lights on P1 and P2.
Receiver on-board LED can be repeated to any non-servo output (this is called the LED2 function).
All functionality may be configured by programming using a a suitable transmitter (most Micron tx
or a stick type model aircraft tx).
Connections, Configurations and Indicators
MR603 power input (positive & negative battery) and motor outputs pads are at one end of the
receiver. The pad spacing is 3.5mm which allows use of a terminal block if screw rather than solder
connection is preferred.
Auxiliary outputs are mostly on the long side of the receiver: 4 x 2A switches (labeled A to D) and 4 x
0V/3.3V logic outputs (labeled P1 to P4). There are also a 3.3V output, 0V (battery negative) outputs
and a 'L' input on the long side closer to the motor pade end. The 'L' input is used to monitor battery
voltage when a booster module is used, e.g. to raise a single LiPo cell to 12V. The 3.3V output can be
used to power attached components, the maximum current from the pin plus anything connected to
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the P outputs is 300mA. These pads have a 2.54mm pitch which allows a pin header to be soldered in
place if plug-in connections are preferred.
Outputs P5 and P6 are at the opposite end of the receiver to the power and motor connections. There
are also pads here for 0V and 3.3V. A JST-SH 4 pin connector may optionally be installed at this
location.
MR603 can be powered from a battery of 4.5V up to 20V. The speed controller will stop the motor if
the battery drops below 4.5V but the other receiver functions will continue to operate down to 2.5V.
The pre-loaded configurations are shown below. Unless otherwise specified when the receiver was
ordered, config 1 is enabled by default. The other loaded configurations can be selected using a power-
on configuration change or by programming.
Port 1: Centre-off
throttle
2: MyLocoSound
triggers on A-D
(Tx22)
3: MyLocoSound
triggers on A-D
(Tx20)
4: Tx with 3-way
toggle on ch2 & ch4
ESC H1 Centre-Off ch1 Centre-Off ch1 Centre-Off ch1 Low-Off ch1, dir ch3
P1 Front Light on H1
(LED2)
Front Light on H1
(LED2)
Front Light on H1
(LED2)
Momentary on ch2,
high 0V
P2 Rear Light on H1 Rear Light on H1 Rear Light on H1 Momentary on ch2,
low 0V
P3 Momentary on ch3,
low 3.3V
Momentary on ch3, low
3.3V
Momentary on ch3, low
3.3V
Momentary on ch4,
high 0V
P4 Momentary on ch3,
high 3.3V
Momentary on ch3,
high 3.3V
Momentary on ch3,
high 3.3V
Momentary on ch4,
low 0V
P5 Momentary on ch5,
low 3.3V
Momentary on ch5, low
3.3V
Momentary on ch5, low
3.3V
Momentary on ch5,
low 3.3V
P6 Momentary on ch5,
low 0V
Momentary on ch5, low
0V
Momentary on ch5, low
0V
Momentary on ch5,
low 0V
F1/A/P7 Front Light on H1 Momentary on ch3,
high closed
Momentary on ch2, low
closed
Front Light on H1
(LED2)
F2/B/P8 Rear Light on H1 Momentary on ch3, low
closed
Momentary on ch4, low
closed
Rear Light on H1
F3/C/P9 Momentary on ch5,
low closed
Momentary on ch5, low
closed
Momentary on ch5, low
closed
Momentary on ch5,
low closed
F4/D/P10 Latch on ch5, start
open, toggle low
Latch on ch5, start
open, toggle low
Latch on ch5, start
open, toggle low
Latch on ch5, start
open, toggle low
LED2 P1 P1 P1 F1
Selecta Enabled Enabled Enabled Disabled
LVC Enabled Enabled Enabled Enabled
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Sleep
time
1 hour 1 hour 1 hour 1 hour
Failsafe Disabled Disabled Disabled Disabled
Port 1: Centre-off
throttle
2: MyLocoSound
triggers on A-D
(Tx22)
3: MyLocoSound
triggers on A-D
(Tx20)
4: Tx with 3-way
toggle on ch2 & ch4
Other configurations are available to special order or you can configure yourself by programming.
P outputs switch between 0V (off) and 3.3V (on). F outputs are switched to negative and are open (off) or
closed (on). LEDs on P pads should be connected between the pad and battery negative (0V) with a series
resistor appropriate to the required brightness. P1 to P4 have a series 180 ohm resistor on the PCB, P5 and
P6 have no resistor. LEDs or incandescent lamps on F pads should be connected between the pad and battery
positive or the 3.3V pad and with series resistor appropriate to the voltage and required brightness.
Sound card inputs are usually 5V open circuit and are triggered when connected to negative. They should be
connected to an F pad. A P pad may be used if you have more trigger inputs than F pads; in this case a 4k7
ohms resistor must be connected in series to avoid stressing the MR603 microprocessor. The P output should
be configured for 3.3V idle and 0V when the Tx control is actioned.
MR603 has 2 LED indicators, one on the top near the aerial and another on the bottom, these are labeled
'LED RF' and 'LED CPU' on the diagram above.
RF LED:
lights continuously when a good signal is received, flashes rapidly when the rx is in bind mode and
flashes intermittently if signal is poor (transmitter too close causing overload or transmitter too far
away)
CPU LED:
indicates the receiver status:
immediately after switch on, emits a 0.5s rapid flash followed by a flash pattern to show the active
configuration (1..4), repeated once: e.g. rapid-flash, pause, 2-flash, pause 2-flash shows that the
receiver is using configuration #2
flashes slowly while waiting for a good transmitter signal
lights continously when a good R/C data is being decoded
flashes twice, pause and repeat when the receiver is deselected (see Loco Selection)
used for feedback when programming; feedback flash patterns comprise a repeated number of
flashes followed by a 1 second pause - this is called a N-flash where N is the number of flashes, e.g.
3-flash is 3 short flashes, 1 second pause and repeat
shows a 5-flash if the low voltage cutoff has triggered - this stops the motor but other outputs
continue to work
displays an error indication if the receiver firmware detects a fault; this is shown as repeated pattern
of 0.5 seconds rapid flashing followed by a N-flash where N is the error code (see Error Codes)
Binding
MR603 must be bound to a transmitter before use. Once bound, MR603 remembers the transmitter identity
and searches for this when it is switched on.
To bind a receiver, it is switched on with no transmitter active (for normal operation, the transmitter should
be switched on before the receiver).
The default MR603 configuration is for autobind where the receiver automatically goes into bind mode approx
10 seconds after switching on with no pre-bound transmitter active. Manual binding may be configured by
programming - this could be useful, for example, if the loco is to be used by children who could forget to
switch the loco/receiver on first.
auto bind:
The receiver enters bind mode approximately 10 seconds after power-on if it has either never been
bound or it fails to find its bound transmitter.
manual bind:
Pads P5 and P5 must be connected before switching the receiver on. If P5 and P6 have no soldered
connections and the JST-SH is not installed, this can be achieved using needle nose tweezers pressed
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onto the pads. Alternatively, and necessary when the receiver is inaccessible, a switch can be wired to
P5 and P6.
Bind mode is indicated by a rapid flashing of the receiver RF LED and the following steps should be followed
to bind with your transmitter:
1. transmitter switched off
2. if Loco Selection is enabled, move the transmitter loco selection switch to the required position
3. switch on the receiver in bind mode (manual or auto)
4. only when the RF LED is flashing rapidly, hold down the transmitter bind button and switch on
5. wait for the transmitter to indicate that it is in bind mode and then release its bind button (the power
LED on Micron model rail transmitters will flash when binding)
6. after a short delay, the RF LED should stop flashing and go dark and, after another 4-5 seconds, both RF
and CPU LEDs will light and stay on
7. the receiver is now bound to the transmitter
If the receiver RF and CPU LEDs do not come on solid (no flash) within 10-15 seconds, the bind process has
failed. This can happen for several reasons and does not normally indicate a fault. During binding, the
receiver searches for the transmitter's signal and this can be distorted by holding the transmitter and receiver
too close. So, if you get a bind fail, try again after moving them slightly further apart or changing the relative
orientation of the aerials. Binding is most reliable when no other 2.4GHz transmitters are turned on.
Loco Selection - Selecta
Many Micron model rail transmitters have a 12 way switch to allow control of up to 12 locos - Deltang
originated this feature and call it 'Selecta'. Using the switch, locos are brought under control one at a time.
When not selected, receiver outputs hold their current setting (e.g. a loco which is moving when deselected
keeps moving) and the CPU LED shows a 2-flash pattern. The default 'keep going' behaviour can be changed
to stop when deselected by programming the receiver.
The Micron implementation of Loco Selection / Selecta is fully compatible with the Deltang Selecta feature
and uses R/C channel 2 by default. When Loco Selection is enabled, the controlling R/C channel (e.g. 2) may
still be mapped to a receiver output but, of course, this will not change as the transmitter switch is rotated.
The receiver has a 800ms delay before enabling when the transmitter Selecta value is changed. This is to
avoid obeying the transmitter while the Selecta switch is being moved - e.g. a receiver on Selecta #4 should
not change any outputs while the transmitter Selecta switch is moved from #3 to #5.
Selecta may be enabled by default (see the receiver configuration information) and may be enabled or
disabled by using a power-on configuration change (see Power-On Configuration Changes).
If Loco Selection / Selecta is enabled, the transmitter's Selecta switch value will be saved when the
transmitter and receiver are bound. A new Selecta value (i.e. switch position) can be stored either by
rebinding or by using the power-on changes to disable and then re-enable Selecta.
Loco Selection / Selecta may also be enabled or disabled by programming.
Directional Lighting
All configurations have pads P1 and P2 setup to drive front and rear LED lights; P1 powers a forward LED and
P2 a backward facing LED. The directional lighting pins can be changed by programming the receiver.
MR603 has an on-board 3.3V regulator and 180 ohm resistors in series with the P1 to P4 so limits the LED
current to approximately 20mAh. Most high brightness LEDs require much less than this so an additional
resistor should be used - e.g. 100 - 1k ohms. The LED should be connected between P1/P2 and battery
negative (0V).
The directional LEDs follow the throttle channel if configured for centre-off, changing when the throttle
passes though the off position. If the speed controller is configured for low-off, the LEDs change only when
the throttle is at zero - i.e. the direction control can be altered at any time but the LEDs (and motor
direction) changes only when the throttle is closed.
The ESC mode (centre or low off) can be changed by programming or by using one of the power-on
configuration changes
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Cruise Control
If the receiver loses the signal from the transmitter, for example when going through a tunnel or behind a
garden building or some dense bushes, MR603 outputs hold their current setting until the transmitter signal
is reaquired. Outputs also hold when a Selecta-enabled receiver (see Selecta) is de-selected.
'Output hold' means that the loco will continue doing whatever it was doing before the loss of signal (or de-
selection). This allows a form of 'cruise control' which allows you to switch off the transmitter if, for example,
you are running the loco round a continuous circuit.
Cruise control can be disabled using a Power-On Change or by programming. If disabled, the motor will be
stopped when signal is lost.
Emergency Stop
Any of the transmitter controls can be used as an 'Emergency Stop' function to rapidly bring the loco/vehicle
to a stop. Emergency Stop is not enabled by default and must be configured by programming the receiver.
To enable Emergency Stop, you need to choose:
the R/C channel
whether a low or high signal is used to trigger
the delay before stopping - i.e. the number of seconds that the R/C channel must be in the trigger state
before Emergency Stop is actioned
For example, the Tx22X transmitter button S2 (in-between the 2 toggle switches) could be used: this
controls R/C channel 4 and the signal is low when the button is pressed.
Power-On Configuration Changes
A few configuration changes can be made without programming. A simple link across 2 of the auxiliary P
pads is used to action the change. This is easily achieved using some needle nose tweezers and, if they are
sharp pointed, can penetrate the receiver's heatshink cover. A change is made by:
connecting the appropriate P pads with the receiver off,
switching the receiver on and observing the LED flash pattern,
removing the connection which is confirmed by a rapid LED flash and then
switching the receiver off.
The changes all toggle (or cycle) each time the process is performed. The LED flash indicates the new state
of the configuration parameter. The receiver has to be switched off after the change as it will be stuck in the
rapid flash mode to indicate that the change has been made. If you switch off before removing the P
connection, the configuration is not changed.
This is a summary of the configuration changes that can be made using a jumper across 2 of the P pads.
Change Pads LED indication
Reset P1/P2 2-fast-flash = reset to saved configuration, or factory setup if no configuration
saved
Selecta P1/P3 1-flash - disabled
2-flash = enabled
Cruise Control P1/P4 1-flash = disabled, stop in 4s after signal loss
2-flash = enabled
ESC Throttle Mode P2/P3 1-flash = centre-off
2-flash = low-off
Configuration
Select
P2/P4 n-flash where 'n' is the configuration number
LVC P3/P4 1-flash = disabled
2=flash = enabled with battery voltage auto-detect
P2/P4 Configuration Select requires further explanation. Each flash count is repeated twice and then
increments to the next, cycling back to 1 when the max (usually 4) is reached. Remove the P2/P4 connection
when the flash count is the configuration you want.
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Receiver Programming
The behaviour for each MR603 pad (ESC, F or P) can be changed using a bound transmitter. MR603 must
first be put into programming mode and then the direction toggle switch, or elevator on a stick type
transmitter, is used to enter a program sequence one digit at a time. The CPU LED (and LED2 if enabled)
flashes to indicate the value of the current step in the programming sequence. For example, if the current
value is 4, the CPU LED flashes 4 times, pauses and repeats - this is called a 4-flash.
The programming table is large and presented in a separate document (see micronrc.co.uk/mr6xx_progtable)
which lists all of the functions that may be changed by programming. The table is split into 5 blocks of related
functions each with the same value in the first column.
The table columns contain the program values which must be entered to change a particular function. For
example, to change the throttle behaviour from centre-off (forward and reverse on one control) to low-off
(separate throttle/regulator and direction/reverser controls) the program sequence 1, 1, 2, 1, 3 is entered.
Each digit of this program sequence is taken from the columns, left to right:
1 = ESC Configuration
1 = H1 (there is only 1 ESC on MR603)
2 = Low Off Throttle
1 = Throttle on R/C channel 1
3 = Direction control on R/C channel 3
One function can be changed at a time. The general method is:
set receiver into programming mode
enter a program sequence
repeat until all programming changes have been made
Enter Programming Mode
There are 2 methods of getting the MR603 into programming mode:
1. hold the transmitter channel 2 and channel 4 controls at high or low extremes and then switch the
receiver on; these are the F1 and F2 buttons on a Tx20v2 and the Selecta switch and S2 button on a
Tx22X; the receiver LED will flash rapidly shortly after switch on, centre one or both channel 2 & 4
controls (e.g. release the buttons on Tx20v2 or the S2 button on Tx22X
2. switch the transmitter and receiver on (they must be bound), wait 5 seconds without touching any
controls and then tap out morse SOS (... --- ...) on the transmitter bind button (or toggle the gear
switch high to low for a stick transmitter);
dots (…) will be a quick press of the button and must be less than 1 second in duration
dashes (---) must be greater than 1 second and shorter than 5 seconds – 2 seconds is a reliable
time
the time between each dot or dash must be less than 5 seconds
When programming mode has been successfully entered, the receiver LED will show a 1-flash - this is the 1
from the first column of the programming table. If you do not get the 1-flash, repeat the procedure to enter
programming mode. It usually takes a couple of attempts to get the SOS method correct if you have never
done it before.
Enter a Program Sequence
One programming change requires up to five choices to be made. These are called 'levels' and each has
several options. They are documented in the programming table. Completion of a programming change exits
programming mode and requires the receiver to be placed into programming mode again for the next
change.
It is a good idea to write the programming sequence on a piece of scrap paper and cross off each digit as it is
entered so that you don't lose track of where you are in the sequence. You always start at the top of the first
column and 1-flash is displayed on entering programming mode.
The flash count for a level is incremented by setting the R/C channel 3 control low and back to mid.
The flash count for a level may be decremented by holding the R/C channel 4 control low while
operating the R/C channel 3 control; R/C channel 4 is available on some Micron transmitters - e.g. F2 on
Tx20v2 and S2 on Tx22X and TX42v2
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The level value is accepted and the flash count for the next level is displayed by setting the R/C channel
3 control high and back to mid.
Most Micron transmitters have a toggle switch on R/C channel 3 which is marked A/B, or forward/reverse for
a low-off transmitter:
pushing the switch down (or toward 'reverse' for a low-off transmitter) sets the R/C channel to a low
value and increments the flash count,
pushing the switch up (or toward 'forward') sets the R/C channel to a high value, accepts flash count
and moves the program sequence on to next level or exit programming mode if the current level is the
last in the sequence
Always return the toggle switch to centre after pushing down or up. Refer to the transmitter user manual for
specific information on the R/C channel 3 control - Tx24v2 has a rotary reverse control.
The receiver LED will flash rapidly while R/C channel 3 is high or low and then return to a slower repeated
flash when the control is back to the middle.
After accepting the flash count for a level, the CPU LED displays a flash count for the current value of the
next level. This could be higher than 1-flash if the function is set in the receiver configuration or has been
previously programmed. For example:
the default Selecta R/C channel is 2, so a 2-flash will be displayed after entering 4, 8, 2
P1 is configured as a front light, so a 4-flash will be displayed after entering 3, 1
When the last level for a sequence has been accepted, the CPU LED will light continously and the receiver is
back in normal operating mode. The maximum number of levels is 5, but not all sequences use all 5; if level
5 in the table is blank, the CPU LED will light continously after level 4 is accepted.
Programming changes are accepted only when the CPU LED lights solid at the end of the sequence. If a
mistake is made mid way through a sequence, switch the receiver off to abort.
Programming Example
These examples assume MR603 is in as-received configuration and a Micron transmitter with toggle switch on
R/C channel 3. Tx24v2 transmitters have a variable control on R/C channel 3 - the Reverser; the equivalent
actions are:
Action Tx with toggle switch Tx24v2 type transmitter
Increment flash count: toggle down Reverser fully CCW (reverse) and back to centre
Accept flash count: toggle up Reverser fully CW (forward) and back to centre
1. Set P4 as servo on R/C channel 7
program sequence: 2, 4, 1, 6
enter programming mode
LED shows 1-flash (level 1, 1=core)
toggle down and release once, LED shows 2-flash (level 1, 2=servo)
toggle up and release, LED shows 1-flash (level 2, 1=P1)
toggle down and release 3 times, LED shows 4-flash (level 2, 4=P4)
toggle up and release, LED shows 1-flash (level 3, 1=servo)
toggle up and release, LED shows 1-flash (level 4, 1=R/C chan 1 - P6 was prevously a GPIO)
toggle down and release 6 times, LED shows 7-flash (level 4, 7=R/C chan 7)
toggle up and release, LED lights continously and servo on P4 responds to R/C channel 7
2. Reverse servo on P4
program sequence: 2, 4, 7, 1
enter programming mode
LED shows 1-flash (level 1, 1=core)
toggle down and release once, LED shows 2-flash (level 1, 2=servo)
toggle up and release, LED shows 1-flash (level 2, 1=P1)
toggle down and release 3 times, LED shows 3-flash (level 2, 4=P4)
toggle up and release, LED shows 1-flash (level 3, 1=normal servo)
toggle down and release 6 times LED shows 7-flash (level 3, 7=adjust servo
toggle up and release, LED shows 1-flash (level 4, 1=reverse servo direction)
toggle up and release, LED lights continously and servo on P4 rotates in the opposite direction
3. Set D/F4 as momentary GPIO, on when R/C channel 4 is low
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program sequence: 3, 10, 1, 4, 1
To be completed
The programming table for MR603 can be found at micronrc.co.uk/mr6xx_progtable.
Servo Throw Adjustment
Servo throws (low and high end points) can be configured using a bound transmitter, the servo centre
position will always be at the mid-point of the low and high travel. To adjust a servo, the servo output is
selected first and then the travel adjusted using either the throttle control or direction toggle if the throttle
servo is being adjusted.
The steps below assume a Micron transmitter is being used. If the transmitter is an aeroplane type stick
transmitter then the elevator stick corresponds to the direction toggle.
put the receiver into programming mode (see above)
enter the program sequence 2, P, 7, 2, where P is the output port number (e.g. 3 for P3)
within 5 seconds, move the control for the output being adjusted to the end that needs adjustment:
use the direction toggle or throttle control to increase or decrease the servo travel:
use the throttle control if the direction (R/C channel 3) servo is being adjusted, or
hold throttle knob fully CCW to decrease travel
hold throttle knob fully CW to increase travel
use the direction toggle for all other servos
hold toggle down to decrease travel
hold toggle up to increase travel
the receiver LED will flash twice per second as the servo travel is being adjusted and stop flashing when
the limit is reached.
centre both controls to finish the adjustment, the receiver will return to normal operating mode after
the control corresponding to the P port being adjusted has been centred for 5 seconds.
Only one servo output can be changed at a time. Go through the above steps to adjust a different servo
output pin.
© Micron Radio Control
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