DemoPad Centro CM - IP Network API Reference Manual

Table of Contents

IPv4 Address
Connection Details
Communication Protocol
Command List
Command Errors
Update Firmware
Troubleshooting

Revision 1.0 - 13^th November 2023

IPv4 Address

When using factory default settings, the Centro CM presents itself as a DHCP Client. Thus, it will be allocated an IPv4 IP address from a local DHCP server.

If you cannot establish the IP address of the Centro CM, see Troubleshooting

Connection Details

The Centro CM presents a TCP Server in order to establish a connection with a TCP socket client application. Ref RFC793.

Data is sent raw (uncooked) and is therefore plaintext. Further application abstraction, such as using a Telnet application is not required. The use of Telnet for the RS-232 / RS485 / RS-422 bridge port is strongly discouraged.

No more than 8 concurrent TCP socket clients can be supported simultaneously on each Centro CM TCP port. Attempting to add more than 4 concurrent connections will result in the 9th attempt being rejected.

By default, TCP sockets are closed by the Centro CM after 2 minutes. This can be altered using the Communication Protocol.

TCP client applications can use either persistent or 'one-shot' connection methods.

The Centro CM listens on 2 discrete TCP socket ports. Connection to a specific port is dependant on the desired function.

TCP Port List:

7500: Communication Protocol
7501: RS-232 / RS-422 / RS-485 Port bridge

Data sent / received via TCP port 7501 are a direct representation of all data sent / received via the related RS-232 / RS-485 / RS-422 port. Data is sent / received “as-is”. Communication on this port is simply a bridge. There is no processing on this port. The Centro CM Communication Protocol does not apply.

All data bytes from 0x00 through to 0xFF are supported.

Data sent / received via TCP port 7500 conforms to the Centro CM communication protocol listed below.

Communication Protocol

Protocol examples will represent data using the ASCII printable character set.

All commands sent from a TCP socket client are to be terminated with a <Carriage Return> character byte. Depending on your TCP socket client application, this may be represented by:

0x0D (Hex)
\r (Escape notation)
$0D (Hercules)
\x0D (Escape byte notation)

Example:

$RELAYSTATUS 1\x0D

All responses sent from the Centro CM are terminated with <Carriage Return><Line Feed> character bytes. Depending on your TCP socket client application, this may be represented by:

0x0D 0x0A (Hex)
\r\n (Escape notation)
{0D}{0A} (Hercules)
\x0D \x0A (Escape byte notation)

Example:

RELAY 01 OPEN\x0D\x0A

Upon establishing a connection with a TCP socket client, the Centro CM will send the welcome message:

Centro-C Firmware Version : V1.7.5\x0D\x0A

N.B. The firmware version shown may differ - see $VERSION

Command List

The command list syntax and examples will represent data using the ASCII printable character set.

Command syntax will use value substitution bounded by the “<” and “>” symbols.

Each line of data in syntax and examples are delimited by the termination symbols, see Communication Protocol.

$VERSION - Return system firmware version

Use this command to return the current Centro CM system firmware version

Command syntax:

$VERSION

Command example:

$VERSION

Return syntax:

Centro-CM Firmware Version : V<vmaj>.<vmin>

Where:

<vmaj> = 0-9
<vmin> = 00-99

Return example:

Centro-CM Firmware Version : V2.15

$RC - Set a relay to a closed state

Use this command to close a specific relay.

Command syntax:

$RC <relay_number>

Where:

<relay_number> = 1-4

The number of the relay with reference to the product chassis labelling

Command example:

Close relay 3

$RC 3

Return syntax:

RELAY <relay_number> CLOSED

Where:

<relay_number> = 00-04

Return example:

RELAY 03 CLOSED

$RO - Set a relay to an open state

Use this command to open a specific relay.

Command syntax:

$RO <relay_number>

Where:

<relay_number> = 1-12

The number of the relay with reference to the product chassis labelling

Command example:

Open relay 3

$RO 3

Return syntax:

RELAY <relay_num> OPEN

Where:

<relay_num> = 00-04

Return example

RELAY 03 OPEN

$RELAYSTATUS - Return the current state of a relay

Use this command to return the current state of a specific relay.

Command syntax:

$RELAYSTATUS <relay_number>

Where:

<relay_number> = 1-4 or ?

The number of the relay with reference to the product chassis labelling. Use ? to return the status of all relays

Command example 1:

Return the state of relay 3

$RELAYSTATUS 3

Command example 2:

Return the state of all relays

$RELAYSTATUS ?

Return syntax:

RELAY <relay_num> <relay_state>

Where:

<relay_num> = 00-04
<relay_state> = OPEN or CLOSED

RELAYSTATUS <r1><r2><r3><r4>

Where:

<r1> = O or C

The state of relay 1, OPEN or CLOSED
<r2> = O or C

The state of relay 2, OPEN or CLOSED

...

<r4> = O or C

The state of relay 4, OPEN or CLOSED

Return example 1 (Command example 1, if the current state of relay 3 is OPEN):

RELAY 03 OPEN

Return example 2 (Command example 2, if the current state of relays is OPEN, CLOSE, OPEN, OPEN):

RELAYSTATUS OCOO

$TRIGGER - Return the current state of all binary input ports

Use this command to return the current state of all binary input ports.

Command syntax:

$TRIGGER

Command example:

$TRIGGER

Return syntax:

INPUTSTATUS <b1><b2><b3><b4><b5><b6><b7><b8>

Where:

<b1> = 0-1

The state of input 1 with reference to the product chassis labelling
<b2> = 0-1

The state of input 2 with reference to the product chassis labelling

...

<b8> = 0-1

The state of input 8 with reference to the product chassis labelling

A closed circuit to the 5V terminal represents a 1 state. An open circuit represents a 0 state.

Return example (closed circuit on each even input number, open circuit on odd inputs):

INPUTSTATUS 01010101

$TRIGGERRELAYS - Set up automatic relay states based on a binary input change

Use this command to set up an automatic state allocation for all product relays based on a state change of a binary input port.

Command syntax:

$TRIGGERRELAYS <input_number> <input_state> <r1><r2><r3><r4>

Where:

<input_number> = 1-8

The number of the binary input port with reference to the product chassis labelling
<input_state> = OPEN or CLOSE

The binary state transition

OPEN = Input port transitions from closed to open state

CLOSE = Input port transitions from open to closed state

A closed circuit to the 5V terminal represents a CLOSE state. An open circuit represents an OPEN state.

<r1> = 0 or 1 or T or -

The desired state of relay 1 with reference to the product chassis labelling

0 = Relay open

1 = Relay closed

T = Relay toggle

- = Relay unaffected

...

<r4> = 0 or 1 or T or -

The desired state of relay 4 with reference to the product chassis labelling

Command example:

When input 5 transitions from closed to open state, open relay 1, close relay 2, toggle relay 3 and leave all other relays unaffected

$TRIGGERRELAYS 5 OPEN 01T-

Return syntax:

TRIGGERRELAYS <input_number> <input_state> <r1><r2><r3><r4>

Return example (using command example)

TRIGGERRELAYS 5 OPEN 01T-

$IREMIT - Emit an IR code from an IR output

Use this command to emit an IR code from a specific IR output port

Command syntax:

$IREMIT <port> <freq>,1,1,<p1on><p1off><p2on><p2off><...><pNon><pNoff>

Where:

<port> = 1-12

The number of the IR output port with reference to the product chassis labelling
<freq> = 4E20 - EA60

The hexadecimal value of the modulation or carrier frequency in Hz
<p1on> = 01 - FFFF

The hexadecimal count value of modulation periods for burst pair 1 on state
<p1off> = 01 - FFFF

The hexadecimal count value of modulation periods for burst pair 1 off state
<p2on> = 01 - FFFF

The hexadecimal count value of modulation periods for burst pair 2 on state
<p2off> = 01 - FFFF

The hexadecimal count value of modulation periods for burst pair 2 off state

...

<pNon> = 01 - FFFF

The hexadecimal count value of modulation periods for the last burst pair on state
<pNoff> = 01 - FFFF

The hexadecimal count value of modulation periods for the last burst pair off state

The on count is the number of periods of (1/modulation_frequency) that equals the burst pair on period.

The off count is the number of periods of (1/modulation_frequency) that equals the burst pair off period.

Relationship with Pronto CCF HEX format IR codes

Example HEX code:

0000 0067 0000 0015 0060 0018 0018 0018 0030 0018 0030 0018 0030 0018 0018 0018 0030 0018 0018 0018 0018 0018 0030 0018 0018 0018 0030 0018 0030 0018 0030 0018 0018 0018 0018 0018 0030 0018 0018 0018
                                    0018 0018 0030 0018 0018 03f6

First word: 0000 - Not used

Second word: 0067 - This is a Pronto CCF format hexadecimal value, that can be represented in decimal (𝑥) representing the modulation frequency (ƒ), where

𝑥 = 1000000 / (ƒ * 0.241246)

The modulation frequency value (ƒ) is used directly for <freq>, so for this example we can rearrange so that

ƒ = 1000000 / (𝑥 * 0.241246)

ƒ = 1000000 / (103 * 0.241246)

ƒ = 40244Hz

and represent as a hexadecimal value, rounded to the nearest integer

<freq> = 9D34

Third word: 0000 - Not used

Fourth word: 0015 - Not used

The remaining words are the hexadecimal burst pair values and can be substituted as a direct sequence to the $IREMIT command after removing any leading zeros.

Command example 1:

Send Pronto CCF HEX format IR code from IR output port 2

0000 0067 0000 0015 0060 0018 0018 0018 0030 0018 0030 0018 0030 0018 0018 0018 0030 0018 0018 0018 0018 0018 0030 0018 0018 0018 0030 0018 0030 0018 0030 0018 0018 0018 0018 0018 0030 0018 0018 0018
                                    0018 0018 0030 0018 0018 03f6

$IREMIT 2 9D34,1,1,60,18,18,18,30,18,30,18,30,18,18,18,30,18,18,18,18,18,30,18,18,18,30,18,30,18,30,18,18,18,18,18,30,18,18,18,18,18,30,18,18,3F6

Relationship with Global Cache format IR codes

Example GC code:

sendir,1:1,1,38000,1,1,341,168,22,19,22,62,22,62,22,62,22,62,22,62,22,62,22,19,22,62,22,19,22,19,22,19,22,19,22,19,22,19,22,62,22,19,22,62,22,62,22,62,22,62,22,62,22,62,22,19,22,62,22,19,22,19,22,19,22,19,22,19,22,19,22,62,22,760

sendir,1:1,1, - Not used

38000, - This is the modulation frequency in Hz. This value can be used directly for <freq> when represented as hexadecimal

1,1, - Not used

The remaining comma-separated values are the decimal burst pair values and can be substituted as a direct sequence to the $IREMIT command when represented as hexadecimal

Command example 2:

Send GC format IR code from IR output port 5

sendir,1:1,1,38000,1,1,341,168,22,19,22,62,22,62,22,62,22,62,22,62,22,62,22,19,22,62,22,19,22,19,22,19,22,19,22,19,22,19,22,62,22,19,22,62,22,62,22,62,22,62,22,62,22,62,22,19,22,62,22,19,22,19,22,19,22,19,22,19,22,19,22,62,22,760

$IREMIT 5 9470,1,1,155,A8,16,13,16,3E,16,3E,16,3E,16,3E,16,3E,16,3E,16,13,16,3E,16,13,16,13,16,13,16,13,16,13,16,13,16,3E,16,13,16,3E,16,3E,16,3E,16,3E,16,3E,16,3E,16,13,16,3E,16,13,16,13,16,13,16,13,16,13,16,13,16,3E,16,2F8

Return syntax:

IR OK

Return example:

IR OK

$REPEATIR - Repeat the last Infrared code a number of times

Use this command to repeat the last IR code a specific amount of times. The last IR code is the code sent with the last $IREMIT command.

Command syntax:

$REPEATIR <repeat>

Where:

<repeat> = 1-255

The number of times to emit the last IR code

Command example:

$REPEATIR 20

Return syntax:

IR OK

NO IR DATA

If there has been no IR sent previously, there will be no data to repeat. See $IREMIT

Return example:

IR OK

$STOPIR - Force the IR that is currently being emitted to stop.

Use this command to immediately stop any IR being emitted.

Command syntax:

$STOPIR

Command example:

$STOPIR

There is no return using this command.

$IRLEARN - Learn a single IR code received by the IR input port

Use this command to learn a single IR code from a 3rd-party IR remote. The output is formatted to the Centro IR format, see $IREMIT

The time window for learning a code is set at 5 seconds.

Command syntax:

$IRLEARN

Command example:

$IRLEARN

Return syntax:

Push Remote Control Button In 5 sec...

At this point, use the 3rd-party IR remote to generate the desired infrared code to be learned.

Followed by:

<freq>,1,1,<p1on><p1off><p2on><p2off><...><pNon><pNoff>

Where:

<freq> = 4E20 - EA60

The hexadecimal value of the modulation or carrier frequency in Hz
<p1on> = 01 - FFFF

The hexadecimal count value of modulation periods for burst pair 1 on state
<p1off> = 01 - FFFF

The hexadecimal count value of modulation periods for burst pair 1 off state
<p2on> = 01 - FFFF

The hexadecimal count value of modulation periods for burst pair 2 on state
<p2off> = 01 - FFFF

The hexadecimal count value of modulation periods for burst pair 2 off state

...

<pNon> = 01 - FFFF

The hexadecimal count value of modulation periods for the last burst pair on state
<pNoff> = 01 - FFFF

The hexadecimal count value of modulation periods for the last burst pair off state

The on count is the number of periods of (1/modulation_frequency) that equals the burst pair on period.

The off count is the number of periods of (1/modulation_frequency) that equals the burst pair off period.

For more information on the data returned, see $IREMIT

If no IR code is received, the command will timeout. No return will be sent.

Return example:

Push Remote Control Button In 5 Sec...
9a35,1,1,5f,18,2f,18,18,18,2f,18,18,18,18,18,18,18,18,18,2f,18,18,18,18,18,18,18,18,403,5f,18,2f,18,18,18,2f,18,18,18,18,18,18,18,18,18,2f,18,18,18,18,18,18,18,18,403,5f,18,2f,18,18,18,2f,18,18,18,18,18,18,18,18,18,2f,18,18,18,18,18,18,18,18,403,5f,18,2f,18,18,18,2f,18,18,18,18,18,18,18,18,18,2f,18,18,18,18,18,18,18,18,403,5f,18,2f,18,18,18,2f,18,18,18,18,18,18,18,18,18,2f,18,18,18,18,18,18,18,18,403,5f,18,2f,18,18,18,2f,18,18,18,18,18,18,18,18,18,2f,18,18,18,18,18,18,18,18,403,5f,18,2f,18,18,18,2f,18,18,18,18,18,18,18,18,18,2f,18,18,18,18,18,18,18,18,403,5f,18,2f,18,18,18,2f,18,18,18,18,18,18,18,18,18,2f,18,18,18,18,18,18,18,18,61e

$COMSTATUS 1 - Return the UART parameters for the RS-232 / RS-422 / RS-485 port

Use this command to return the UART parameters set for a specific RS-232 / RS-422 / RS-485 port

Command syntax:

$COMSTATUS 1

Command example:

$COMSTATUS 1

Return syntax:

COM 1 IS SET TO : <baud>,<byte>,<parity>,<stop>

Where:

<baud> = 1200, 2400, 4800, 9600, 19200, 38400, 57600 or 115200

The baud rate of the UART
<byte> = 8 or 9

The number of bits used in the data byte
<parity> = N, E or O

The use of the parity bit. None, Even or Odd
<stop> = 1-2

The number of stop bits

Note that on the Centro CM, the size of the data byte is fixed at 8 bits.

Return example:

COM 1 IS SET TO : 115200,8,N,1

$COM_SET 1 - Set the UART parameters for the RS-232 / RS-422 / RS-485 port

Use this command to set the UART parameters for the RS-232 / RS-422 / RS-485 port

Command syntax:

$COM_SET 1 <baud>,<byte>,<parity><stop>

Where:

<baud> = 1200, 2400, 4800, 9600, 19200, 38400, 57600 or 115200

The baud rate of the UART
<byte> = 8 or 9

The number of bits used in the data byte
<parity> = N, E or O

The use of the parity bit. None, Even or Odd
<stop> = 1-2

The number of stop bits

Command example:

Set the UART parameters for RS-232 port 4

$COM_SET 1 19200,8,N,1

Return syntax:

SET COM 1 <baud>,<byte>,<parity>,<stop>

Return example:

SET COM 1 19200,8,N,1

$COM_MODE 1 - Set the line signal mode for the RS-232 / RS-422 / RS-485 port

Use this command to set the line signalling mode parameter for the RS-232 / RS-422 / RS-485 port. The options on the Centro CM are 3-wire RS-232, full-duplex RS-422 or half-duplex RS-485.

Command syntax:

$COM_MODE 1 <sig>

Where:

<sig> = RS232, RS422 or RS485

The line signalling mode

Command example:

$COM_MODE 1 RS422

Return syntax:

COM 1 IS SET TO <sig> MODE

Return example:

COM 1 IS SET TO RS422 MODE

$SETIP - Set static values for IP address, netmask and gateway IP address

Use this command to set static values for host IP address, netmask and gateway IP address. This will disable the DHCP client service.

If you are not careful, this is an easy way to lose communication with the Centro CM product. If you encounter a problem after using this command, see Troubleshooting

Command syntax:

$SETIP <host_ip> <netmask> <gateway_ip>

Where:

<host_ip> = IP Address

The host IP address in dotted octet format, .e.g. 192.168.2.1
<netmask>

The netmask in dotted octet format, .e.g. 255.255.255.0
<gateway_ip> = IP Address

The gateway IP address in dotted octet format, .e.g. 192.168.2.254

Command example:

$SETIP 192.168.10.106 255.255.255.0 192.168.10.254

There is no return using this command. The new setting will be set after a few seconds. Note, you will need to establish a new TCP socket connection.

$ETH_MODE 1 - Enable the DHCP client service for the network interface

Use this command to set the ethernet interface to use the DHCP client service. This will allow the Centro CM to obtain the host IP, netmask and gateway IP from the local DHCP server.

This will replace any statically assigned host IP, netmask and gateway IP values.

If you are not careful, this is an easy way to lose communication with the Centro CM product. If you encounter a problem after using this command, see Troubleshooting

Command syntax:

$ETH_MODE 1

Command example:

$ETH_MODE 1

There is no return using this command. The new setting will be set after a few seconds. Note, you will need to establish a new TCP socket connection.

$IPCONFIG - Return the current network interface details

Use this command to return the current Ethernet interface details

Command syntax:

$IPCONFIG

Command example:

$IPCONFIG

Return syntax:

ETHERNET MAC : <mac_address>
Address Type : <type>
IP : <host_ip>
SN : <netmask>
GW : <gateway_ip>
Telnet COM 1 PORT : 7501

Where:

<mac_address> = MAC Address

The MAC address in hyphenated hexadecimal format, e.g. 40-d8-55-1a-53-72
<type> = DHCP or Static IP

The addressing mode of the Network interface
<host_ip> = IP Address

The host IP address in dotted octet format, .e.g. 192.168.2.1
<netmask>

The netmask in dotted octet format, .e.g. 255.255.255.0
<gateway_ip> = IP Address

The gateway IP address in dotted octet format, .e.g. 192.168.2.254

Return example:

ETHERNET MAC : 40-d8-55-1a-53-72
Address Type : Static IP
IP : 192.168.2.1
SN : 255.255.255.0
GW : 192.168.2.254
Telnet COM 1 PORT : 7501

$TELNET_TIMEOUT - Set the TCP socket server connection timeout mode

Use this command to set a 2 minute timeout for all TCP client connections. For each client, if the client application sends no data for 2 minutes the Centro CM will disconnect the TCP socket.

Command syntax:

$TELNET_TIMEOUT <en_timeout>

Where:

<en_timeout> = ON or OFF

ON = Enable the timeout mode

OFF = Disable the timeout mode

Command example:

$TELNET_TIMEOUT ON

Return syntax:

SET TELNET TIMEOUT <en_timeout>

Return example:

SET TELNET TIMEOUT ON

$FACTORY - Reset the Centro CM to factory default values

Use this command to return the Centro CM to factory default settings.

If you are not careful, this is an easy way to lose communication with the Centro CM product. If you encounter a problem after using this command, see Troubleshooting

Command syntax:

$FACTORY

Command example:

$FACTORY

There is no return using this command. All TCP clients will be disconnected within 20 seconds. Note, you will need to establish a new TCP socket connection.

$REBOOT - Reboot the Centro CM

Use this command to reboot the Centro CM and release all TCP socket connections.

Command syntax:

$REBOOT

Command example:

$REBOOT

There is no return using this command. All TCP clients will be disconnected within 20 seconds. Note, you will need to establish a new TCP socket connection.

Command Errors

If the Centro CM encounters command data that contains an error, the returned data depends on the error:

Incorrect command keyword

Wrong Command!!

Incorrect command parameters

Command failed

Update Firmware

Updating Centro CM firmware will also restore the product to its factory default settings. Only update firmware if instructed to by DemoPad Support.

To update the firmware on the Centro CM, please download the latest firmware ZIP file from this link: Latest Firmware: Centro CM

To update the Centro CM firmware

Format a USB Flash storage device to FAT32.
Copy the firmware file to the root directory of the USB Flash drive.
Using the Centro CM Communication Protocol, send the command:
```
$UPDATE USB
```
Immediately after, insert the USB Flash drive into the USB port on the Centro CM.
The update should only take a few seconds. During this time there is no LED light activity on the product.
If done correctly the unit's power light will stay red for 5-10 seconds and then flash green which means the update was successful.
Turn off the power to the Centro CM and remove the USB Flash drive before turning the Centro CM on again.

Troubleshooting

I do not know the IP address of the Centro CM or I cannot connect to the Centro CM

Power off the Centro CM. Wait a few seconds. Turn on the power to the Centro CM.
Observe the DHCP address allocation for the Centro CM on your DHCP server.

If you cannot see a DHCP-allocated address for the Centro CM or suspect that the Centro CM has been set to use a static IP address, you can force the Centro CM to enable the DHCP client by restoring factory default values.

To achieve a Factory Reset state, use a blunt object to depress the internal push-button as indicated in the picture:

Once you press and hold the button, the LED inside will turn red.
Keep holding the button for 10 seconds.
After 10 seconds, release the button.
The Centro CM will perform a factory reset and reboot.

Some data sent / received from a RS-232 / RS-422 / RS-485 port is incomplete or incorrect

Check that you are using a raw TCP socket client application. Using Telnet or another application layer to abstract or wrap data through additional protocols or standards will likely result in some data not being represented correctly.
Check the UART parameters set for the RS-232 / RS-422 / RS-485 port are correct relative to the 3rd-party equipment connected by serial. This includes the line signalling mode, the baud rate, number of bits used in the data byte, the use of a parity bit and the number of stop bits.