PerlDCBDataStructure

Perl DCB Data Structure

Data is transferred to or from the thermostat via a binary Device Control Block (DCB). For convenient manipulation the Perl scripts convert this to and from an internal data structure composed of nested hash and array references.

All Thermostats

Primary Key	Secondary Key	Read/Write	Description
{config}	{progmode}	R	Feature 12 (or 16 for RF models): Thermostat program mode (5/2 or 7)
{dcblength}		R	Length of the DCB in octets
{enabled}		R/W	Thermostat off (0) or on (1)
{holiday}	{enabled}	R/W	Home (0) or away (1)
{holiday}	{time}	R/W	End of holiday (YYYY-MM-DD hh:mm:ss), if {enabled}
{keylock}		R/W	Touch screen unlocked (0) or locked (1)
{product}	{model}	R	Thermostat model (DT, DT-E, PRT, PRT-E, PRTHW or TM1)
{product}	{vendor}	R	Thermostat manufacturer (Heatmiser or OEM)
{product}	{version}	R	Thermostat version number (#.#)
{time}		R/W	The date and time (YYYY-MM-DD hh:mm:ss)

Heating Controllers

Primary Key	Secondary Key	Read/Write	Description
{config}	{caloffset}	R	Calibration offset (#####)
{config}	{locklimit}	R	Feature 7 (or 11 for RF models): Temperature limit when locked (0...10)
{config}	{optimumstart}	R	Feature 10 (or 14 for RF models): Optimum start disabled (0) or maximum hours (1...3)
{config}	{outputdelay}	R	Feature 5: Output delay in minutes (0...15)
{config}	{sensor}	R	Feature 8 (or 12 for RF models): Sensor selection (internal, remote, floor, internal + floor or remote + floor)
{config}	{switchdiff}	R	Feature 2: Switching hysteresis (0.5, 1.0 or 1.5)
{config}	{units}	R	Feature 1: Temperature format (C or F)
{errorcode}		R	Error code (internal, floor, or remote) or undef for none
{frostprotect}	{enabled}	R	Feature 3: Frost protection disabled (0) or enabled (1)
{frostprotect}	{target}	R/W	Feature 4: Frost protection temperature (##)
{heating}	{hold}	R/W	Hold time in minutes (#####)
{heating}	{on}	R	Heating off (0) or on (1)
{heating}	{target}	R/W	Target heating temperature (##)
{rateofchange}		R	Feature 11 (or 15 for RF models): Learnt rate of temperature rise in minutes/°C (###)
{runmode}		R/W	Heating operating mode (heating or frost)
{temperature}	{remote}	R	Remote temperature (##.#) or undef
{temperature}	{floor}	R	Floor temperature (##.#) or undef
{temperature}	{internal}	R	Internal air temperature (##.#) or undef

Primary Key	Secondary Key	Tertiary Key	Quaternary Key	Read/Write	Description
{comfort}	[#]	[#]	{time}	R/W	Start time for the comfort level (hh:mm:00)
{comfort}	[#]	[#]	{target}	R/W	Comfort level temperature (##)
	(0/1 for Weekday/Weekend 0...6 for Monday...Sunday)	(0...3 index within the day)

Underfloor Heating Controllers

Primary Key	Secondary Key	Read/Write	Description
{floorlimit}	{floormax}	R/W	Feature 9 (or 13 for RF models): Floor temperature limit (##)
{floorlimit}	{limiting}	R	In floor limit state (1) or not (0)

Hot Water Controllers

Primary Key	Secondary Key	Read/Write	Description
{awaymode}		R/W	Hot water operating mode (home or away)
{hotwater}	{boost}	R/W	Boost time in minutes (#####)
{hotwater}	{on}	R/W	Hot water off (0), on (1) or let timer run (undef, for W only)

Primary Key	Secondary Key	Tertiary Key	Quaternary Key	Read/Write	Description
{timer}	[#]	[#]	{on}	R/W	Start time for the hot water (hh:mm:00)
{timer}	[#]	[#]	{off}	R/W	End time for the hot water (hh:mm:00)
	(0/1 for Weekday/Weekend 0...6 for Monday...Sunday)	(0...3 index within the day)

Notes

• The Perl scripts represent dates and times as strings using the same format as SQL. Specifically, the current time and end of holiday are in DATETIME (YYYY-MM-DD HH:MM:SS) format, and programmed comfort levels and hot water timers are in TIME (HH:MM:SS) format.
• Boolean values are represented by 0 (off/disabled) and 1 (on/enabled).
• Enumerated values (other than boolean) are generally represented by text strings. However, if the DCB contains an unrecognised value then its raw numeric value is used instead.
• Temperatures are specified in the configured units (Feature 1). The learnt rate of temperature change (Feature 11, or 15 for RF models) is always in minutes/°C.
• Many settings (including most of the 'Features') cannot be set remotely; they must be adjusted via the thermostat's touchscreen.