Driver Manual
6.4Writing data to Dap Devices
The variables in a DAP device are not individually addressable . When a DAP device is read a data composite is returned. The driver extracts the data you require. When data is written to a DAP device it is not possible to write a value to one individual data element such as a temperature setpoint. Rather, the DAP devices requires the complete data composite (all its variables, states, settings) be written at once. This makes the setting of a setpoint a complex operation for the driver.
It involves the following steps
i.Read the device, obtain a complete set of data and store (internally in the driver.).
ii.Use this stored data to form the basis for a write. Modify the data with the data the user wishes to set.
iii.Write the modified data composite back to the DAP device.
You can see that to complete a 'write' operation successfully, we must first read the device successfully. If the read has not been completed then the write operation will be abandoned. The driver prints messages to the error logs and records a NODE_OFFLINE stat each time that it attempts to write but is unable to.
The
If any inhibit bit (bits
0x01 - Inhibit Cooling
0x02 - Inhibit Heating
0x04 - Inhibit Humid
0x08 - Inhibit Dehumidification
0x10 - Inhibit fan
0x20 - Reserved
0x40 - Network Standby - Display on panel (only has no effect on unit) 0x80 - Network off inhibit is active - display only - no effect on operation
This function should be used as a wrbc/x. When the driver encounters this command it reads the associated data array, loads the two elements found at the array offset into the message and transmits the message. The driver does not set any data array elements to confirm that the command concluded successfully.
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