Pump Control

Controlling the ALPHA HWR (Start, Stop, Change Mode) involves sending specific Class 10 DataObject commands. Unlike simple registers, these commands require a strict sequence of operations, including packet fragmentation and a "Configuration Commit" step.

Control Object

All primary control operations target the following GENI object:

Class: 10 (0x0A)
SubID: 0x5600 (Operation/Control)
ObjID: 0x0601 (Mode Configuration)
Operation: SET (OpSpec typically 0x90)

The Control Sequence (Critical)

Due to hardware limitations and firmware logic, sending a control command is not a simple atomic write. The following three rules must be observed:

1. MTU Fragmentation (Split-Writes)

The ALPHA HWR BLE interface has a hard Maximum Transmission Unit (MTU) of 20 bytes for write operations. * Control packets are typically 24 bytes long. * Action: You must split the packet into two writes. 1. Write bytes 0-19. 2. Wait a small duration (e.g., 10ms). 3. Write remaining bytes (20-23). * Failure to split causes the device to silently drop the packet or return a CRC error.

2. Transaction Locking

The pump streams telemetry at ~10Hz. If a telemetry read request or notification is interleaved between the two fragments of your control command, the device's buffer will be corrupted. * Action: Ensure exclusive access to the BLE characteristic during the split-write sequence.

3. Configuration Commit

Even after successfully writing the control command, the pump may revert to its previous state immediately unless the change is "committed". * Action: Send a specific "Configuration Commit" packet immediately after the control command.

Remote Control Mode

The ALPHA HWR can be placed in "Remote Control Mode", which changes how it prioritizes external commands over the physical operating panel.

Overview

Override Local Control: When active, the pump prioritizes commands from the Bluetooth interface and ignores most button presses on the physical panel.
Persistence: Once enabled, the pump stays in Remote Mode until it is explicitly returned to "Auto" (local) control.
Command Lock: This is recommended when an external controller (like a home automation system) is managing the pump's logic to prevent accidental local overrides.

Technical Implementation

Remote mode uses the legacy Class 3 (Register) protocol:

Enable Remote: Command ID 7 (0x03 C1 07)
Disable Remote (Auto): Command ID 6 (0x03 C1 06)

These commands are sent to the standard GENI Service ID 0xE7 from Source 0xF8.

Packet Structure

Control Command Payload

The payload for Sub 0x5600, Obj 0x0601 follows this structure:

2F 01 00 00 07 00 [RunState] [Mode] [Suffix...]

Offset	Field	Value	Description
0-1	Header	`2F 01`	Fixed header for this object.
2-5	Padding	`00 00 07 00`	Fixed padding/flags.
6	Run State	`0x00` or `0x01`	`0x00` = START / RUN `0x01` = STOP
7	Mode	`0x00` - `0xFF`	Control Mode ID (see below).
8-11	Suffix	Variable	Mode-specific parameters (often `45 65 70 00`).

Configuration Commit Packet

This packet confirms the changes. * Target: Sub 0x5400, Obj 0xDA01 * OpSpec: 0x93 * Full Packet Hex: 27 17 E7 F8 0A 93 54 00 01 00 DA 01 00 00 0A 02 05 00 05 00 01 00 00 00 00 F1 EE

Supported Control Modes

The Mode byte determines the regulation behavior.

ID	Name	Description
`0`	Constant Pressure	Maintains constant differential pressure.
`1`	Proportional Pressure	Adjusts pressure based on flow.
`2`	Constant Speed	Runs at a fixed RPM (Default).
`5`	AutoAdapt	Automatically analyzes system needs (generic).
`8`	Constant Flow	Maintains a specific flow rate.
`13`	AutoAdapt Radiator	AutoAdapt optimized for radiator systems.
`14`	AutoAdapt Underfloor	AutoAdapt optimized for underfloor heating.
`15`	AutoAdapt Combined	AutoAdapt for combined radiator + underfloor systems.
`25`	DHW On/Off	Domestic Hot Water control.

AutoAdapt Mode Variants

The three AutoAdapt variants (IDs 13, 14, 15) are system-specific optimizations:

Radiator (13): Optimized for high-temperature radiator systems with steeper pump curves.
Underfloor (14): Optimized for low-temperature underfloor heating with flatter curves.
Combined (15): Balanced optimization for mixed radiator and underfloor systems.

Each AutoAdapt mode has dedicated factory configuration Sub-IDs for reading setpoint limits and defaults.

Example: Start Pump in Constant Speed

To start the pump in Constant Speed mode (Mode 0x02):

Construct Payload:
- Run State: 0x00 (Start)
- Mode: 0x02
- Payload: 2F 01 00 00 07 00 00 02 45 65 70 00
Wrap in GENI Frame:
- Class 10, OpSpec 0x90, Sub 5600, Obj 0601.
- Full Packet: 27 14 E7 F8 0A 90 56 00 06 01 2F 01 00 00 07 00 00 02 45 65 70 00 [CRC]
Split & Send:
- Write 27 14 ... 00 (20 bytes).
- Write 02 45 65 70 00 [CRC] (Remaining bytes).
Send Commit:
- Write 27 17 E7 ... F1 EE (Commit packet).

Setpoint Configuration

Each control mode has factory-configured minimum, maximum, and default setpoint values stored in the pump's non-volatile memory.

Factory Configuration Object

Setpoint limits are stored in:

Class: 10 (0x0A)
Object: 86 (0x56)
Sub-IDs: Mode-specific (see table below)

Setpoint Limit Sub-IDs

Each control mode maps to a specific Sub-ID in Object 86 for reading its setpoint configuration:

Control Mode	Sub-ID	Data Format
Constant Speed	13	3x uint16 (min, max, default) in RPM
Constant Pressure	15	3x uint16 (min, max, default) in Pascals
Proportional Pressure	17	3x uint16 (min, max, default) in Pascals
AutoAdapt Radiator	19	3x uint16 (min, max, default) in Pascals
AutoAdapt Underfloor	21	3x uint16 (min, max, default) in Pascals
AutoAdapt Combined	23	3x uint16 (min, max, default) in Pascals
Constant Flow	39	3x uint16 (min, max, default) in m³/h

Reading Setpoint Limits

To read limits for Constant Pressure (Sub-ID 15):

Send Read Request:
- Class 10, OpSpec 0x90, Object 86, Sub-ID 15
- Full Packet: 27 0C E7 F8 0A 90 56 00 00 86 00 0F [CRC]
Parse Response:
- Response payload contains 6 bytes after header
- Bytes 0-1: Minimum setpoint (uint16, big-endian)
- Bytes 2-3: Maximum setpoint (uint16, big-endian)
- Bytes 4-5: Default setpoint (uint16, big-endian)
Unit Conversion:
- Pressure modes: Pascals ÷ 9806.65 = meters
- Speed modes: RPM (no conversion)
- Flow modes: m³/h (no conversion)

Example: Response 03 CE 09 8F 06 0A decodes to: * Min: 974 Pa = 0.99 m * Max: 2447 Pa = 2.50 m * Default: 1546 Pa = 1.58 m

Validation Workflow

Before setting a new setpoint value:

Read the appropriate factory limits using read_setpoint_limits(control_mode)
Validate the desired value is within [min, max] range
If valid, proceed with the control command
If invalid, reject and inform the user

The AlphaHWRClient.validate_setpoint() method automates this process with two modes:

Non-strict (default): Logs warning if limits unavailable, allows setpoint anyway
Strict: Fails validation if limits cannot be read

Cumulative Statistics

The pump stores cumulative operational statistics in non-volatile memory:

Class: 10 (0x0A)
Object: 93 (0x5D)
Sub-ID: 1

Statistics Data Format

The response payload is 31 bytes total (including 3-byte header):

Offset	Field	Type	Description
0-2	Header	`00 00 XX`	Fixed header bytes
11-14	Operating Time	uint32	Total seconds of operation
15-18	Start Count	uint32	Number of motor starts

Both values are big-endian (network byte order).

Example: To read statistics:

Send Read Request:
- Full Packet: 27 0C E7 F8 0A 90 5D 00 00 93 00 01 [CRC]
Parse Response:
- Extract bytes 11-14: Operating time in seconds
- Extract bytes 15-18: Start count
- Convert seconds to hours: hours = seconds / 3600

Example Response: * Bytes 11-14: 00 05 CD E8 = 380,392 seconds = 105.7 hours * Bytes 15-18: 00 00 02 70 = 624 starts