SEM88 – 8 Port Serial Switch V1

SSH Console Serial Switch with Environmental Monitoring

8-port SSH Console Serial Switch with AC power. Connect up to 8 devices with different baud rates, parity, and character length. Supports two environment monitoring sensors.

The device is designed to transmit serial communication and monitoring of climate change (by temperature).
The device is built to meet the needs management following communication interfaces LAN, USB, RS232 and serial
Multiprotocol Transceiver (RS232 / RS422 / RS485)
For the purpose of transmission of serial information is built-in 8 Multiprotocol transceivers.
The device is built for 4 sensor connector. Said sensor connectors have one GPIO input and output.
Power plants can be AC 230V and DC-48V.

The device is built with ARM technology (LPC1769)

Management interfaces are connected directly to the communication interfaces of the CPU itself.

To connect the serial communication is used RJ45 connectors.
The connection is according to EIA-561 Interface (RS232 / RJ45)
8 Serial communication interface coupled via I2C0 and I2C1 bus to the CPU. In the mentioned bus is
coupled p 4 I2C UART (SC16IS752).
Interrupts from individual UART ICs are connected directly to the CPU.

Electrical serial connector type is controlled via the GPIO connections UART IC.
Via these connections are made, the following controls:
1st Choice between voltage (RS232) and current (RS422 and RS485) port (control signal to 232-1
2nd choice between semi-duplex (RS485) and Full-duplex interface (RS422)
The control signals 422-1 to 422-8
3 Check the reception and submission of the RS485 communication is carried out via the CTS connector on the UART.
4 termination of the current terminals is carried out via the THER-1 to THER-eighth

LED Indication of serial communication is connected to the TTL connections Multiprotocol transceivers. In addition,
LED status indications intended for serial communication is built-in LED indicator set electric
interface type (voltage or current).

For the purposes of measurement of temperature and humidity are used I2C sensors SI7005.

Control of the sensors is carried out through the CPU bus I2C2.
In the guide is connected to the I2C MUX PCA9548APW. From said MUXa the ports P0-P3 are connected to the
RJ45 connectors. Port P4 is intended for the sensor which is situated on the PCB apparatus (for testing purposes).

Check the power supply of sensors is carried out via the I2C2 bus.
Turning on each adapter itself and control is implemented through U8 (PCA9554A).
The control circuit of each power section are two double AP2152 (U30 and U33).
LED status indication of each sensor connector is conducted through U7 (PCA9555DBQ) which is
connected at I2C2 guide.
For each sensor an RJ45 connector is intended by four LEDs for indicating status.

In addition to the I2C bus, power supply to the sensor connectors are connected to one GPIO inputs and outputs.

Screen Shot 2014-08-14 at 16.09.54

Screen Shot 2014-08-14 at 16.10.52

Screen Shot 2014-08-14 at 16.12.40 Screen Shot 2014-08-14 at 16.12.45 Screen Shot 2014-08-14 at 16.12.54


10352988_483285751807825_2218376107187194216_n 10384831_483285768474490_7510643901377823728_n 10497885_483285745141159_2254008470781339196_o 10505287_483285758474491_9207787492395792614_n

IMG_1764 IMG_1763 IMG_1755 IMG_1765

PCB: Milan Cunjak

Software: Luka Penger

Company: Initra d.o.o.

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