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All Paradox MG, SP, and EVO panels include a built-in TTL 5V serial port. PAI communicates with the panel over this port using the Serial connection type.

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Hardware requirements

The panel’s serial port operates at TTL 5V logic levels. Depending on how you connect, you may need additional hardware.
Raspberry Pi GPIO operates at 3.3V. Connecting directly to the panel’s 5V serial port can damage the GPIO pins. You need a bidirectional level shifter (e.g. a 3.3V–5V logic level converter) between the Pi’s UART pins and the panel.Once wired through the level shifter, the serial port typically appears as /dev/ttyS0 or /dev/ttyAMA0 depending on your Pi model and OS configuration.
A USB-to-TTL adapter lets you connect from any host with a USB port without GPIO wiring. Commonly supported adapters include:
  • CP2102
  • PL2303
  • CH340
These enumerate as /dev/ttyUSB0 (or /dev/ttyUSB1, etc.) on Linux.
Paradox manufactures a dedicated USB 307 module for connecting directly from a PC’s USB port to the panel. It is treated as a standard serial port by the OS.

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Common serial port paths on Linux

PortTypical use
/dev/ttyS0, /dev/ttyS1On-board UART (x86/x64 servers, some SBCs)
/dev/ttyAMA0Raspberry Pi primary UART
/dev/ttyUSB0First USB serial adapter (CP2102, PL2303, CH340)
/dev/ttyUSB1Second USB serial adapter
PAI will attempt to set read/write permissions on the port automatically if they are not already set.

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Baud rates by panel family

The correct baud rate depends on your panel model:
Panel familyBaud rate
SP (Spectra)9600
MG (Magellan)9600
EVO (standard)38400 or 57600
EVO+ versions115200
Do not upgrade EVO firmware to version 7.50.000 or later if you use a serial connection. Paradox introduced serial communication encryption in that version, which prevents PAI from communicating with the panel. This is irreversible unless you purchase an unlock code from Paradox.

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Configuration

Set the following options in pai.conf:
OptionDefaultDescription
CONNECTION_TYPE'Serial'Must be set to 'Serial'
SERIAL_PORT'/dev/ttyS1'Path to the serial device
SERIAL_BAUD9600Baud rate matching your panel family
PASSWORDNone4-digit PC password from Babyware. Set to None if not configured
The PASSWORD is the PC Communication password, not the user PIN. Find it in Babyware by right-clicking your panel and choosing Properties → PC Communication (Babyware) → PC Communication (Babyware) tab.

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Example configuration

CONNECTION_TYPE = 'Serial'
SERIAL_PORT = '/dev/ttyS1'
SERIAL_BAUD = 9600
PASSWORD = '0000'
If PAI cannot open the serial port, check that the user running PAI is a member of the dialout group (sudo usermod -aG dialout $USER). PAI will also attempt to fix permissions automatically on startup.

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