Communication

Warning!

This section applies to all Control Point series: the Control Point and Control Point VAV.

The Control Point panel has one RS485 bus accessible by 2 RJ45 ports and a 4-pin connector.

RS485

There are 3 communication protocols that can be selected using the DIP switch 2 and PROTOCOL field:

	DIP Switch 2	PROTOCOL (40024)
Modbus RTU	Off (default)	0 (default)
Modbus ASCII	Off	1
BACnet MS/TP	On	N/A

Setting communication protocol

Setting MAC Address

The device's MAC address can be set using the following register:

ADDRESS: contains information about the Modbus address of the room panel. The default address is 1;

Modbus register: 40023;
BACnet object: N/A.

Setting Communication Parameters

BACNET_DEVICE_ID: sets the device's BACnet ID;

Modbus register: 40016;
BACnet object: DEVICE, property: Object Identifier;

BAUD_RATE: sets a baud rate of the panel. The baud rate is calculated according to the formula: baud rate = (register's value)⋅10. The default value is 11520 (115200 bps);

Value	Baud Rate (bps)
240	2400
480	4800
960	9600
1920	19200
3840	38400
5760	57600
7680	76800
11520	115200 (default)

Baud rate values

Modbus register: 40017;
BACnet object: DEVICE, property: 3084.

STOP_BITS: determines a number of stop bits in a Modbus frame;

Value	No. of Stop Bits
1	1 (default)
2	2

Values of the STOP_BITS register

Modbus register: 40018;
BACnet object: N/A.

DATA_BITS: determines a number of data bits in a Modbus frame (the Modbus ASCII protocol requires 7 bits):

Value	No. of Data Bits
7	7
8	8 (default)

Values of the DATA_BITS register

Modbus register: 40019;
BACnet object: N/A;

PARITY_BITS: each byte of data being transferred may have an additional protection of a parity bit added before stop bit (bits). The 16-bit register determines a number of added parity bits;

Value	No. of Parity Bits
0	None (default)
1	Odd
2	Even

Values of the PARITY_BITS register

Modbus register: 40020;
BACnet object: N/A;

Note: The BACnet protocol requires specific values of stop bits, data bits, and a parity bit of 1, 8, and none, respectively. Therefore, the user settings for these objects are not applicable.

REPLAY_DELAY: determines a number of milliseconds before the panel answers the request. This time is used to extend the interval between the request and response. The default value of 0 means no delay (the response is sent once during the 3,5 character required by the Modbus RTU protocol).

Modbus register: 40021;
BACnet object: N/A.

WARNING!

The above parameters are remembered, but NOT automatically set. In order to set these parameters to the panel, it is required to perform one of the following actions after entering required values:

restart the panel;
send a reload settings command (0: 0x2FF, DEVICE (property: 3030): 0x2FF, iSMA Configurator, or FCU Updater).

Incoming data frames are counted and presented through the following parameters:

RECEIVED_FRAMES: shows the number of received frames. The register's value is reset at the start of the panel and at the change of transmission parameters;

Modbus register: 30004;
BACnet object: DEVICE, property: 5101 (VALID_FRAMES_FOR_US_ CNT);

ERROR_FRAMES: shows the number of error messages (shorter than 3 or with incorrect CRC value) received by the panel from the time of the last power-up. The register's value is reset at the start of the panel and at the change of transmission parameters;

Modbus register: 30006;
BACnet object: DEVICE, property: 5103 (ERROR_FRAMES_CNT);

TRANSMITTED_FRAMES: shows the number of sent frames. The register's value is reset at the start of the panel and at the change of transmission parameters;

Modbus register: 30008;
BACnet object: DEVICE, property: 5104 (TRANSMITTED_FRAMES_ CNT).

USB

A USB bus is accessible through the USB C port at the bottom of the device. Device identifies itself as a USB HID, and can be configured using the iSMA Configurator and FCU Updater software.