The function block has the following input pins in, disable, overrideoff and the output of the number of stages turned on is provided by Stages_Active. This function is a generic stage driver or a Thermostat Stage Cycler dependant on the value of the CPH parameter.
Logic Inputs
| Input Name | Input Value | Logic Value | Description |
| disable | unconnected | 0 | Normal operation |
| VAL != 0.0 | 1 | Disable block, output = 0 | |
| 0 | 0 | Normal operation | |
| invalid | 0 | Normal operation | |
| overrideOff | unconnected | 0 | Normal operation |
| VAL != 0.0 | 1 | Turns off stages as min on time allows. | |
| 0 | 0 | Normal operation | |
| invalid | 0 | Normal operation |
Analog Inputs
| Range | ||||
| Input Name | Low | High | Input Value | Description |
| in | 0 | 100 | Unconnected | stgsAct = 0 |
| (%) | invalid | in = 0% | ||
| maxStgs | 1 | 255 | unconnected | stgsAct = 0 |
| invalid | maxstgs = 1 | |||
| minOn | 0 | 64799 | unconnected | stgsAct = 0 |
| (sec) | invalid | stgsAct = 0 | ||
| minOff | 0 | 64799 | unconnected | stgsAct = 0 |
| (sec) | invalid | stgsAct = 0 | ||
| instgOn | 0 | 64799 | unconnected | stgsAct = 0 |
| (sec) | invalid | stgsAct = 0 | ||
| instgOff | 0 | 64799 | unconnected | stgsAct = 0 |
| (sec) | invalid | stgsAct = 0 | ||
Output
| Output Name | Range | Description |
| STAGES_ACTIVE | 0 to +100 % | The number of stages active (on) |
Setpoints
| Name | Range/Value | Description |
| anticipatorAuthority | 0 to 200% | User specified value. Typical value is 100% |
| cph | 1 to 60 | User specified value. |
| hyst | 0 to 100 | User specified value. |
Configuration
Cycler Functionality
The Cycler function is the traditional anticipator cycling algorithm used in Honeywell thermostats. Input is ether P or PI space temperature error in % (0-100). Standard (recommended) settings are cph=3 for cooling, cph = 6 for heating, anticAuth = 100%, hyst = 100%/maxstages/2. Also, for multiple stage cyclers the PID block feeding this block should have an appropriately large throttling range to achieve smooth behavior.

Stager Functionality
The Stager Function takes a 0-100 percent (typically PID error) input and determines how many stages to turn on. The 0-100 percent input range is divided evenly between how many stages are configured in MaxStages. The first stage is turned on at CmdPercent > 0 and off at CmdPercent < - Hyst. As shown in following illustration the general criterion for turning on stage N is:
CmdPercent > (N -1)*100%/MaxStages.
For turning off stage N the criterion is:
CmdPercent < (N -1)*100%/MaxStages - Hyst.
From iteration to iteration, the Function Block keeps track of the on timer, off timer, anticipator, and CPH multiplier. On power up/reset, the off timer and anticipator are cleared, the on timer is set equal to the inter-stage on time and the CPH multiplier is recalculated.

When override is true, active stages are shed (turned off) based on min on and interstage timers regardless of the CmdPercent input. Output is number of stages active (0-MaxStages) which can be sent to the StageDriver function block. Configuration parameters include:
- MaxStages is the maximum stages available to turn on.
- CPH (non-zero) is max cycle rate in Cycles Per Hour when input is halfway between stages available and AnticAuth is at default value (100%). CPH = 0 means the Stager logic is performed and has no other effect.
- Hyst is the switching differential around the switch points in % error. (Range: 0 < Hyst < 100/Maxstgs.)
- AnticAuth (cycler only (CPH != 0)) is the anticipator authority, which allows adjustment of the cycling behavior. It represents the max amount of fake error in % that is input into the switching logic when MaxStages are turned on. (Range 0 < AnticAuth < 200.)
- MinOnTime is minimum time a stage must be on once it is turned on.
- MinOffTime is minimum time a stage must be off once it is turned off.
- InterstageOn is minimum time before the next stage can be turned on after the previous one is turned on.
- InterstageOff is minimum time before the next stage can be turned off after the previous one is turned off.