In the field of industrial automation motion control, efficiently integrating high-performance motion control cards with specific brand servo drives is a key link in system integration. The DIN-814M-J3A launched by ADLINK is a 4-axis interface adapter board designed specifically for Mitsubishi J3A series AC servo drives. It is also compatible with stepper motor drivers and provides standardized signal routing solutions for motion control cards such as PCI-8134, PCI-8164, PXI-8164, and MPC-8164. This article will provide you with a complete technical guide from the dimensions of hardware architecture, interface definition, jumper configuration, typical applications, and troubleshooting.
Product positioning and hardware overview
DIN-814M-J3A is a passive adapter board (passive backplane), whose core function is to convert the 100 pin SCSI main interface (CN1/CN2) of the motion control card into industrial terminals for easy on-site wiring. It supports up to 4 motion axes, each axis providing two interface options:
CNIF # (# represents axis numbers 1-4): a 50 pin dedicated interface, compatible with Mitsubishi J3A series servo drives (such as MR-J3A-A/B models), including complete instructions, feedback, control, and status signals.
SJ #: A 10 pin simple interface used to connect stepper motor drivers or other drivers that support pulse+direction input, including pulse, direction, enable, alarm, and power output.
Important warning: CNIF # and SJ # on the same axis are directly short circuited (signal parallel) inside the PCB. It is strictly prohibited to use two interfaces at the same time, otherwise it may cause signal conflicts and hardware damage.
In addition, each axis is equipped with an IOIF # (9-pin mechanical I/O interface) for connecting limit switches (PEL/MEL), origin signal ORG, deceleration signal (PSD/MSD), reset RES, and external emergency stop EX-EMG. Simultaneously provide BH # auxiliary interface (10 pins) for expanding other signals defined by Mitsubishi J3A, such as speed/torque command, speed arrival, zero speed, torque limit, etc. The board is powered by an external+24VDC power supply (CN1) to provide energy to all isolated side circuits.
Interface Definition and Signal Explanation
1. CNIF # Mitsubishi J3A servo interface (50 pins)
This is the core interface of DIN-814M-J3A, used to connect Mitsubishi J3A series servo drives. Analyze key signals by functional grouping as follows:
Pulse/Direction Command (Differential)
Explanation of Pin Signal Direction
10 OUT+output pulse signal positive terminal
11 OUT - Output pulse signal negative terminal
35 DIR+output direction signal positive terminal
36 DIR - Negative terminal of output direction signal
Encoder feedback (differential input)
Explanation of Pin Signal Direction
4 EA+input encoder A-phase positive terminal
5 EA - Input encoder A negative terminal
6 EB+input encoder B-phase positive terminal
7 EB Input Encoder B Negative Terminal
8 EZ+input encoder Z-phase positive terminal
9 EZ - Input encoder Z-negative terminal
Control and status signals
Explanation of Pin Signal Direction
15 SVON output servo enable (Servo On)
16 SP2 output speed selection 2 (for multi speed switching)
17 ABSM outputs forward rotation command (for absolute value system)
18 ABSR outputs reverse rotation command
41 ERC output deviation counter cleared
42 EMG output emergency stop (to driver)
45 LOP output control selection (switching control mode)
19 RES input reset signal (from external)
22 ABSB0 input speed arrival signal
23 ZSP input zero speed signal
24 INP input positioning completion signal
25 TLC input limit torque signal
48 ALM input servo alarm
49 RDY input servo ready
2 VLA output simulation speed limit (0~± 10V)
27 TC output analog torque command (0~± 10V)
1 P15R output+15V power supply (for external circuit power supply)
20,21+24V output isolation+24V output (provided by external power supply)
Special note:
ABSM/ABSR/ABSB0 is a signal used by Mitsubishi J3A for absolute value encoder communication and status feedback, and non absolute value mode is not necessary.
SP2, when combined with other speed selection pins, can achieve multi-stage speed control. Please refer to the Mitsubishi manual for details.
VLA/TC is an analog command that can be used for speed/torque control mode, but attention should be paid to the corresponding parameter settings of the driver.
2. IOIF # Mechanical I/O Interface (9-pin)
9-pin connectors corresponding to each axis, used to connect limit, origin, deceleration, and emergency stop signals:
Explanation of Pin Signal Direction
1+24V power supply external+24V (for sensor power supply)
2 EX-EMG input external emergency stop signal (low level valid)
3 PEL input positive direction limit
4 MEL input negative direction limit
5 PSD input forward deceleration signal
6 MSD input negative deceleration signal
7 ORG input origin signal
8 RES input reset signal
9 EXGND external ground (shared with other pins of IOIF)
Differences in PSD signal function (related to sports card models):
When combined with PCI-8134, PSD serves as a forward deceleration signal (Slow Down).
When combined with PCI-8164/PXI-8164/MPC-8164, the PSD of axis 0/1 is mapped to CMP1/2 (compare output), and the PSD of axis 3/4 is mapped to LTC3/4 (latch input). Please refer to the corresponding sports card manual for specific functions.
3. SJ # stepper interface (10 pins)
Used for stepper motor drivers or other brands of servos (pulse direction mode):
Explanation of Pin Signal Direction
1+24V power isolation+24V output
2 EX-EMG input external emergency stop (parallel with IOIF)
3 PEL input positive limit
4 MEL input negative limit
5 PSD input forward deceleration
6 MSD input negative deceleration
7 ORG input origin
8 RES input reset
9 EXGND external ground
Attention: The EX-EMG, limit and other signals of SJ are directly connected to the corresponding pins of IOIF internally, only with different wiring positions.
4. BH # auxiliary interface (10 pins)
Provide additional signals for users to directly connect critical signals without using the CNIF main cable:
Explanation of Pin Signal Direction
1 OUT+output pulse+
2 OUT - Output pulse-
3 DIR+output direction+
4 DIR - Output Direction-
5 EZ+input Z-phase+
6 ALM input alarm
7+5V output+5V power supply (for encoders or sensors)
8 SVON output enabled
9+5V output+5V power supply
10 EXGND external ground
5. CN1 external power supply and emergency stop input (2-pin)
Pin signal description
1 EXGND external power ground
2 EX+24V external+24V power input (DC 24V ± 5%)
This power supply supplies power to all isolated side circuits, and it is recommended to provide a current of 1A or above.
6. Jumper J1~J4 (EMG signal source selection)
Each axis corresponds to a jumper (J1~J4) used to select the source of the emergency stop signal:
Jumper position function
1-2 Short circuit EMG signal directly connected to EXGND (i.e. internal forced emergency stop), external EX-EMG invalid (normally closed mode)
2-3 Short circuit EX-EMG (from IOIF or SJ) to the driver EMG pin, external emergency stop switch is active
Default: The factory setting is usually set to 1-2 short circuits (external emergency stop disabled). If an external emergency stop button is required, the jumper must be changed to a 2-3 short circuit, and the emergency stop switch must be connected in series between EX-EMG and EXGND (normally closed contact, disconnected or short circuited when pressed? The manual states "While EX-EMG and EXGND are open, the motor will not move." This means that the motor stops when EX-EMG and EXGND are disconnected, so the emergency stop button should be normally closed, triggering an emergency stop when disconnected).

Typical wiring guidance
1. Mitsubishi J3A servo drive connection
Use the 50 pin 1:1 dedicated cable provided by ADLINK (one end connected to CNIF # and the other end connected to driver CN1A or CN1B). If self-made, it is necessary to strictly follow the pin definitions for corresponding connections.
Connect the CN2 (100 pin SCSI) of the motion control card to the CN1 (or onboard backup CN1) of DIN-814M-J3A via a flat cable.
Set the J1~J4 jumper according to whether an external emergency stop is used (2-3 short circuits are recommended).
Connect the external+24V power supply to CN1.
Connect sensors such as limit and origin to the corresponding terminals of IOIF #, paying attention to the sensor type (NPN/PNP) that matches the input characteristics of the board (input is low level valid, i.e. EXGND triggered).
Before powering on, check all wiring and confirm that there are no errors before powering on.
2. Connection of stepper motor driver
Connect the pulse+, pulse -, direction+, and direction - of the stepper driver to the OUT+, OUT -, DIR+, and DIR - of SJ #, respectively.
If the driver requires an enable signal, connect SVON; If alarm input is required, connect to ALM (but SJ does not have ALM and requires BH or CNIF extension).
Use+24V to power the driver optocoupler (if needed).
Attention: SJ is connected in parallel with CNIF signal, and CNIF must be left vacant.
3. Wiring of limit, origin, and deceleration sensors
Connect PEL, MEL, ORG, PSD, MSD to the output terminals of the corresponding proximity switch or micro switch, and connect the other end of the switch to EXGND or+24V, depending on the sensor type (NPN low effective or PNP high effective). The input of the board is optocoupler isolated and triggered at a low level (short circuit to EXGND), so it is recommended to use NPN type sensors.
If a normally closed limit is used, it is normally at a high level (through a pull-up resistor) and pulled low when triggered.
4. External emergency stop circuit
Connect one end of the external emergency stop button (normally closed contact) to EX-EMG of IOIF # and the other end to EXGND.
Ensure that the J1~J4 jumper is placed in a 2-3 short circuit.
During normal operation, EX-EMG and EXGND are conductive (low level). When the emergency stop button is pressed, the contact opens and EX-EMG remains suspended (high level). The driver receives the EMG signal and stops.
5. Analog command (speed/torque)
If speed or torque control mode is required, the D/A output of the motion card can be connected to the VLA (speed limit) or TC (torque command) pin, and the driver parameters need to be configured for analog command mode.
Principles and Compatibility of Circuit Interface
The manual provides internal circuit structures for various signals (see schematic diagram) to facilitate understanding of load capacity:
Limit/origin/deceleration input: optocoupler isolation, input side needs to be connected in series with a current limiting resistor (onboard), input current is about 5-10mA, low level is effective.
EX-EMG input: Similar to limit, but directly connected to jumper selection circuit.
SVON/ERC output: collector open circuit output, needs to be externally pulled up to+24V (there is already a pull-up resistor inside the board).
Differential pulse/direction: RS-422 drive, can directly drive the differential receiver.
Encoder feedback input: differential receiver, built-in 120 Ω terminal resistor.
Common problems and troubleshooting
Problem 1: After the servo is enabled, the motor does not rotate and there is no alarm
Check whether the CNIF cable is connected correctly and whether there are pulse outputs at OUT ± and DIR ± (which can be measured with an oscilloscope).
Check if SVON is at high level (usually requires activation of the sports card software). Measure the SVON pin voltage of CNIF, which should be close to+24V.
Check if the driver parameters are set to the "pulse+direction" command mode and if the command pulse input method matches.
Problem 2: Invalid limit or origin signal
Check whether the PEL/MEL/ORG of the IOIF terminal is correctly connected to the sensor and whether the sensor is powered (+24V).
Check: The sensor type matches the input polarity of the board (low validity). If PNP is used, additional conversion or change of software polarity is required.
Check if the sports card software has enabled the hardware limit function.
Problem 3: External emergency stop cannot be triggered
Check if the J1~J4 jumper wires are placed in a 2-3 short circuit.
Inspection: Check if the emergency stop button contacts are normal. When normally closed, EX-EMG and EXGND should be conductive (the multimeter measures a resistance of about 0 Ω), and when pressed, they should be disconnected.
Check whether the EMG input of the drive responds correctly (refer to the alarm display on the drive panel).
Problem 4: PSD function does not meet expectations
Confirmation: The sports card model you are using. If it is 8134, PSD is the deceleration signal; If it is the 8164 series and PSD is mapped to CMP or LTC, please refer to the corresponding manual for configuration.
Problem 5: Simultaneous use of CNIF and SJ leads to anomalies
Root cause: The two signals are short circuited, and a physical alternative must be chosen. If switching is required, it is recommended to use external relays or jumper caps, but the board does not provide them, so only one can be chosen.
Maintenance and safety recommendations
Regularly check the tightness of wiring terminals, especially for power and emergency stop circuits.
Do not plug or unplug connectors while they are live to prevent static damage.
Keep the board clean to avoid short circuits caused by metal dust.
It is recommended to adopt a dual channel redundant design for the emergency stop circuit. This board only provides a single signal and needs to be combined with safety relays to enhance reliability.
If used for high security level equipment, please comply with relevant safety standards and regulations.
