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EMS-ESP has a telnet server that enables clients to connect using a telnet client such as PuTTY or natively via the OS like this example with Windows. The port is 23.

You can also access the console via a USB Serial port, using baud 115200.

The console will give you more insight into the EMS bus traffic, MQTT queues and the full device information its capturing. It behaves similar to a Unix/Linux shell. Some of the most common commands are:

  • help or F1 lists the commands and keywords. This works in each context.
  • exit will exit the console or exit the current context. CTRL-D does the same.
  • CTRL-U for Undo
  • <TAB> for auto-complete
  • system to enter the system menu. Use exit or CTRL-D to return.
  • su will switch to the "super user" or admin mode. The default password is ems-esp-neo and can be changed with passwd from the system menu or via the Web interface (called secret password). When in su mode the command prompt switches from $ to #.
  • Some settings can be changed in the console. The set command will list them.
  • The default timeout for telnet is 10 minutes, if you want to change it use set timeout <min>, 0 disables timeout.
  • show or F2 shows the data specific to the which context you're in. From the root it will show you all the EMS device information and any external Dallas temperature sensors.
  • show commands or call will list all the commands which can called with the call command. See Commands.
  • log sets the logging level. log off disables logging. Use log debug for debugging commands and actions, log all includes the telegrams like watch on. This will be reset next time the console is opened.
  • watch will output the incoming Rx telegrams directly to the console. You can also put on a watch on a specific EMS device ID or telegram ID or unknown (new) telegrams. Also choose to output as verbose text as raw data bytes.

Console Commands~

The full list of console commands are shown below:

log [level]
show system
show users
show devices
show ems
show values
show mqtt
show commands
test [name] [data]
wifi reconnect
set wifi password
set hostname <name>
set wifi ssid <name>
set board_profile <name>
set bus_id <device ID>
set tx_mode <n>
scan [deep]
read <device ID> <type ID> [offset] [length]
watch [off | on | raw | unknown] [ID]
call [device] [cmd] [data] [id|hc]


Calling a command to change values~

Note you have su first to get access to all the call commands.


Showing device values~


Monitoring the EMS traffic~

Using the watch command you can monitor the incoming EMS telegrams.

Syntax is watch on <ID> where ID is either a Telegram ID and also a Device ID.

Note the CRC byte is excluded from the data package.

If you want to see only telegrams that are not registered yet, use watch unknown

If you want to see the raw bytes including CRC as transmitted on the EMS line use watch raw <ID>.