HDx23 Hardware Interfaces

This section describes the characteristics and operation of all connectors on the HD223 and HD1023.

Power Connector

The power connector for the HD223 and HD1023 is rated for 12V@1.5A. The plug is a 3.5mm barrel power connector.

3.5mm Serial

The UART (asynchronous serial) interface is a 3.5mm (1/8") jack that uses TTL for communication. The receiver will tolerate input voltages between -30V and +30V, with anything below 3V interpreted as a logical 1. The transmitter drives +5V for logical 0 and 0V for logical 1.

Note

The serial transmit pin does not comply with voltage levels for RS-232 signaling (which requires a voltage below -3V for logical 1). In practice, the serial port can interoperate successfully with the majority of RS-232 receivers, but some devices (including some projectors and Crestron equipment) require strict conformance to RS-232 levels and will not accept 0V as logical 1. In these instances, you can connect the BrightSign player to the serial device using a USB-to-serial cable.

The default baud rate of the interface is 115200, with no parity, 8 data bits, and 1 stop bit. These settings can be configured in the software. The serial interface supports TX, RX, and ground only—RTS/CTS hardware flow control is not supported. The following diagram illustrates the behavior of the TX and RX signal:

The 3.5mm serial port has the following configuration (from the perspective of the player):

Tip: Receive
Ring: Transmit
Sleeve: Ground

BrightSign players are DCE devices, so communication with another DCE device that uses a 3.5mm port would require a null-modem cable or converter that transposes the TX/RX signals. If the device communicating with the player is a DTE device with a DE-9 (more commonly referred to as DB-9) serial port (performing asynchronous transmission), the serial cable should be wired as shown in the following diagram:

GPIO

The HD223 and HD1023 have a 12-pin GPIO switch and LED connector, which allows the player to control external LEDs or other devices requiring 24mA of current or less.

The GPIO port is a standard design manufactured by Phoenix Contact, Wurth Electronics, and others. Pluggable GPIO terminal blocks can be inserted into the GPIO connector to make bare-wire contacts (see here for an example part). These terminal blocks can be purchased from the BrightSign Store. If you wish to source your own terminal blocks, make sure to use 4-pin or 6-pin blocks (12-pin blocks are extremely difficult to remove from the GPIO port).

If you are using the GPIO connector to drive LEDs, connect the LED outputs to the LED ANODE and connect the LED CATHODE to the ground. If you want to connect another device, then the output is capable of sourcing or sinking up to 3.3V at 24mA, but there is a series resistor of 100Ω in each line.

The GPIO also allows for connecting of external contact closures to the ground. In order to connect a switch, connect one side of the switch to the switch input, and connect the other side to one of the ground pins on the GPIO connector. The connector can also supply 3.3V at up to 500mA to an external device. The 3.3V output is polyfuse-protected and can source up to 500mA.

If one BrightSign player is driving the inputs on another BrightSign player, then you can drive at most three inputs from one output. The following calculations explain this limitation:

Note

The GPIO outputs have 100Ω series resistors; the GPIO inputs have 1K pullup resistors to 3.3V; and the input threshold is 2V high and .8V low. The high voltage is not problematic, but the low voltage can be if there are too many inputs connected to one output.

1 out driving 1 in	V=3.3*100/(100+1,000)=0.3
1 out driving 2 in	V=3.3*100/(100+500)=0.55
1 out driving 3 in	V=3.3*100/(100+333.3)=0.76
1 out driving 4 in	V=3.3*100/(100+250)=.94 (This is too high, so 1 output driving 3 inputs is the maximum)

The following table describes the pinout of the GPIO on the HD223 and HD1023:

Pin	Function	Pin	Function

Pin	Function	Pin	Function
1	GND	7	GND
2	3.3V	8	3.3V
3	BUTTON 0	9	BUTTON 4
4	BUTTON 1	10	BUTTON 5
5	BUTTON 2	11	BUTTON 6
6	BUTTON 3	12	BUTTON 7

The following schematic illustrates the pinout of the GPIO connector.

RJ45 LAN

The HD223 and HD1023 have an RJ45 connector for 1000BASE-T networking. The maximum length for Cat 5E cable is 100 meters; the allowed length can be higher or lower depending on the quality of the cable.

USB

The HD1023 has one USB 2.0 Type-A port, which is capable of transfer speeds up to 480 Mbit/s.

The USB connector can supply up to 1A of power for peripherals. The maximum length for a USB cable is 5 meters.

The following table illustrates the pinout of the USB 2.0 Type A host port:

pin	Description	pin	Description

pin	Description	pin	Description
1	VBUS	2	D-
3	D+	4	Ground

3.5mm Audio Connector

The HD223 and HD1023 have a combination analog/optical audio jack. To transmit a digital audio signal, use a TOSLINK optical audio cable with a 3.5mm connector. Analog and digital audio cannot be transmitted simultaneously.

The full-scale voltage output of the analog audio is 2V RMS. The minimum load impedance is 32Ω.

The analog audio connector has the following pinout:

Tip: Left audio
Ring: Right audio
Sleeve: Ground for audio signal

HDMI Output

The HDMI^® output is an HDMI 1.4a connector used to send digital video and audio to HDMI-enabled sink devices. It is capable of outputting a maximum video resolution of 1920x1080x60p.

The following table illustrates the pinout of the HDMI connector:

pin	Description	pin	Description

pin	Description	pin	Description
1	TX2p	2	Ground
3	TX2n	4	TX1p
5	Ground	6	TX1n
7	TX0p	8	Ground
9	TX0n	10	TXCp
11	Ground	12	TXCn
13	CEC	14	NC
15	DDC SCL	16	DDC SDA
17	Ground	18	+5V DDC
19	HPD (Hot Plug Detect)	--