> For the complete documentation index, see [llms.txt](https://docs.verifone.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.verifone.com/hardware-products/hardware/engage-devices/ux1-3-4xx-series/ux3xx/ux300-installation-guide/port-pinouts.md).

# Port Pinouts

The following tables list the port pinouts for the UX300-series persistent board (see Figure 2 in [Setup](/hardware-products/hardware/engage-devices/ux1-3-4xx-series/ux3xx/ux300-installation-guide/setup.md)) and the model-dependent boards.

## Persistent Board Ports

Refer to the following port pinout diagrams for the persistent board.

### Power Port

{% columns %}
{% column %}
**Connector**

![](/files/lLdXPpW9f6akto7rXxoq)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4
{% endcolumn %}

{% column %}
**Function**

9 V to 12 V

GND

WAKE\_VMC\_MF

NC
{% endcolumn %}

{% column %}
**Description**

External power from cable

Power ground

Low active wake up signal

No connection
{% endcolumn %}
{% endcolumns %}

### RS-232 Port (COM1)

{% columns %}
{% column %}
**Connector**

![](/files/vgpFLp9sORc6SxQYJKEB)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4

5

6

7

8
{% endcolumn %}

{% column %}
**Function**

Portpwr (9 V to 12 V)

NC

NC

GND

RXD

TXD

CTS

RTS
{% endcolumn %}

{% column %}
**Description**

Power Out Imax = 0.5 A

No connection

No connection

Power ground

Receive data

Transmit data

Clear to send

Request to send
{% endcolumn %}
{% endcolumns %}

{% hint style="info" %}
The 10-pin download cable (VPN 26264) connects to the 8-Pin RS-232 port of the device, wherein Pin 2 from the cable corresponds to Pin 1 on the RS-232 port.
{% endhint %}

### UX400 8-Pin Port

{% columns %}
{% column %}
**Connector**

![](/files/b0ayBX9o4wlzSEnkIByU)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4

5

6

7

8
{% endcolumn %}

{% column %}
**Function**

+5 V

STBY 3.3 V

GND

nNT\_Proximity

SDA

SCL

M3\_SCL

M3\_SDA
{% endcolumn %}

{% column %}
**Description**

Power

Standby

Power ground

Signal

Signal

Signal

Signal

Signal
{% endcolumn %}
{% endcolumns %}

### Ethernet Port (LAN)

{% columns %}
{% column %}
**Connector**

![](/files/lYWWeChU4uNT38rDW20E)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4

5

6

7

8
{% endcolumn %}

{% column %}
**Function**

TXD+

TXD-

RXD+

NC

NC

RXD-

NC

NC
{% endcolumn %}

{% column %}
**Description**

Transmit data +

Transmit data -

Receive data +

No connection

No connection

Receive data -

No connection

No connection
{% endcolumn %}
{% endcolumns %}

### USB Pinout (Host Port)

{% columns %}
{% column %}
**Connector**

![](/files/W7YCB4lsAq0OiRu2i4kb)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4
{% endcolumn %}

{% column %}
**Function**

+5 V

DATA-

DATA+

GND
{% endcolumn %}

{% column %}
**Description**

5 V USB Power (500 mA)

USB Host Signal -

USB Host Signal +

USB ID pin/Ground
{% endcolumn %}
{% endcolumns %}

### USB Pinout (Client Port)

{% columns %}
{% column %}
**Connector**

![](/files/nDXaI3qfeYaNZPFweT6t)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4
{% endcolumn %}

{% column %}
**Function**

+5 V

DATA-

DATA+

GND
{% endcolumn %}

{% column %}
**Description**

5 V USB Power

USB Device Signal-

USB Device Signal+

USB Ground
{% endcolumn %}
{% endcolumns %}

## Model-Dependent Board Ports

Refer to the following diagrams for the model-dependent board ports.

### Power Port (DC-in MDB)

Applies to UX300-LAN, UX300-PSTN, UX300-ISDN and UX300-MDB.

{% columns %}
{% column %}
**Connector**

![](/files/NnEYu3NzvFSQoDdzwR5g)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4

5

6
{% endcolumn %}

{% column %}
**Function**

V\_MDB

MDB\_PGND

MDB\_WAKE

MDB\_RxD

MDB\_TxD

MDB\_GND
{% endcolumn %}

{% column %}
**Description**

9 V to 43 V, external power from cable

Power ground

Wake signal

Receive

Transmit

Signal Ground
{% endcolumn %}
{% endcolumns %}

### Power Port (DC-in)

Applies to UX300-WPWR.

{% columns %}
{% column %}
**Connector**

![](/files/RzwEVTqFgLuLoaH5koac)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4

5

6
{% endcolumn %}

{% column %}
**Function**

V\_MDB

MDB\_PGND

NC

NC

NC

NC
{% endcolumn %}

{% column %}
**Description**

9 V to 43 V, external power from cable

Power ground

No connection

No connection

No connection

No connection
{% endcolumn %}
{% endcolumns %}

### Power Port (DC-in or Printer)

Applies to UX300-Petrol.

{% columns %}
{% column %}
**Connector**

![](/files/JvTTjCHuzYSEOXzvcqE0)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4

5

6
{% endcolumn %}

{% column %}
**Function**

+24 V

GND

+24 V - Printer

GND - Printer

NC

NC
{% endcolumn %}

{% column %}
**Description**

External power from cable

Power ground

Power to TG-2460H printer

Printer ground

No connection

No connection
{% endcolumn %}
{% endcolumns %}

### USB Pinout (Host Port)

Applies to all variants, except UX300-WPWR.

{% columns %}
{% column %}
**Connector**

![](/files/JgBCl7ItOLJfzuHAsOeN)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4
{% endcolumn %}

{% column %}
**Function**

+5 V

DATA-

DATA+

GND
{% endcolumn %}

{% column %}
**Description**

5 V USB Power (500 mA)

USB Host Signal -

USB Host Signal +

USB ID pin/Ground
{% endcolumn %}
{% endcolumns %}

### Ethernet Port (LAN)

Applies to UX300-LAN.

{% columns %}
{% column %}
**Connector**

![](/files/o4VIjx6H89yeLEt7dCTd)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4

5

6

7

8
{% endcolumn %}

{% column %}
**Function**

TXD+

TXD-

RXD+

NC

NC

RXD-

NC

NC
{% endcolumn %}

{% column %}
**Description**

Transmit data +

Transmit data -

Receive data +

No connection

No connection

Receive data -

No connection

No connection
{% endcolumn %}
{% endcolumns %}

### RS-232 Port (COM2)

Applies to UX300-LAN, UX300-MDB, UX300-Petrol.

{% columns %}
{% column %}
**Connector**

![](/files/o4VIjx6H89yeLEt7dCTd)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4

5

6

7

8
{% endcolumn %}

{% column %}
**Function**

V\_MDB

NC

NC

GND

RXD

TXD

CTS

RTS
{% endcolumn %}

{% column %}
**Description**

9 V to 43 V

No connection

No connection

Power ground

Receive data

Transmit data

Clear to send

Request to send
{% endcolumn %}
{% endcolumns %}

### Printer Port (COM3)

Applies to UX300-LAN, UX300-Petrol, UX300-PSTN, UX300-ISDN and UX300-MDB.

{% columns %}
{% column %}
**Connector**

![](/files/o4VIjx6H89yeLEt7dCTd)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4

5

6

7

8
{% endcolumn %}

{% column %}
**Function**

RTS

CTS

V\_MDB

V\_MDB

GND

NC

RXD

TXD
{% endcolumn %}

{% column %}
**Description**

Ready to send

Clear to send

9 V to 43 V

9 V to 43 V

Receive data

No connection

Receive data

Transmit data
{% endcolumn %}
{% endcolumns %}

### RS-485 RJ9 Port (COM4)

Applies to UX300-Petrol.

{% columns %}
{% column %}
**Connector**

![](/files/CdiIXGMPkjZ5O1bgsgQc)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4
{% endcolumn %}

{% column %}
**Function**

485-

GND\_ISOLATE

485+

NC
{% endcolumn %}

{% column %}
**Description**

RS485 Signal -ve

Isolated Ground

RS485 Signal +ve

No connection
{% endcolumn %}
{% endcolumns %}

### PSTN RJ9 Port (Line)

Applies to UX300-PSTN.

{% columns %}
{% column %}
**Connector**

![](/files/CdiIXGMPkjZ5O1bgsgQc)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4
{% endcolumn %}

{% column %}
**Function**

a

La

Lb

b
{% endcolumn %}

{% column %}
**Description**

No Connect

Tip

Ring

No Connect
{% endcolumn %}
{% endcolumns %}

### ISDN RJ9 Port (Line)

Applies to UX300-ISDN.

{% columns %}
{% column %}
**Connector**

![](/files/CdiIXGMPkjZ5O1bgsgQc)
{% endcolumn %}

{% column %}
**PIN**

1

2

3

4
{% endcolumn %}

{% column %}
**Function**

a1

a2

b2

b1
{% endcolumn %}

{% column %}
**Description**

RX+

TX+

TX-

RX-
{% endcolumn %}
{% endcolumns %}

### RS-485 3-Pin Port

Applies to UX300-Petrol.

{% columns %}
{% column %}
**Connector**

![](/files/logMACibjQxjD7wgmlus)
{% endcolumn %}

{% column %}
**PIN**

1

2

3
{% endcolumn %}

{% column %}
**Function**

485-

485+

GND\_ISOLATE
{% endcolumn %}

{% column %}
**Description**

RS485 Signal -ve

RS485 Signal +ve

Isolated Ground
{% endcolumn %}
{% endcolumns %}


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