Software » Campo

h1. Intro

With the TDT-Protocol sensors can just send their values on the BUS without complex object catalogue.
An monitor-software is able to display values without knowing anything about the sensors or their configuration.
The CANId cinsists of an function code and the node id. Like CANOpen the function code is 4 Bits and the Node-ID is 7 Bit.
In CAN2.0A there can only be 128 Nodes.

CAN 2.0A: 0..0x7FF
CANOpen: 4 Bit Function code, 7 Bit Node-ID
Node-Id: 0..0x7F
Function-Code Mask: 0x780
There are 14 or 28 Filters on STM32Fs
Some STM32 have an internal 96-bit unique ID.

|_. Bits |_. Area |_. Decription |_. Examples |
| 4 |/2.CAN-Id | Function code | Send object |
| 7 | NodeId | Sensemux WZ |
| 16 |/4.Data | Object | Set illumination |
| 8 | Unit | promilPwm |
| 8 | Flags | Confirmation required |
| 32 | Value | 350‰ |



h2. Function code

|_. Code |_. Decription |_. Examples |
| 0x0 | NMT-Write | |
| 0x1 | NMT-Send | |
| 0x2 | NMT-Introduce | Device sends UID only |
| 0x3 | NMT-setId | Set NodeId on Device |
| 0x4 | Alarms | |
| 0x5 0x4 | Write object | Set Date, illumination |
| 0x6 0x5 | Read object | Get product codes |
| 0x7 0x6 | Send object | Send temperature |
| 0x8 0x7 | Resend object | Replay recorded data |
| 0x9 0x8 | data blob | |



h1. IDs, ranges and commands

h2. Node IDs

* 11-Bit-Identifier, (CAN 2.0A); 2048; 0x0 ... 0x7F0; 0x0 ... 0x7F with function code
* 29-Bit-Identifier, (CAN 2.0B); 0x20000000

|_. Range |_. Decription |_. Examples |
| 0x01-0x0F | Network Manager | PC |
| 0x10-0x2F | Active controller | CANDis |
| 0x30-0x4F | Actor | CANSwitch |
| 0x50-0x6F | Sending sensors | Sensemux, CANIO |
| 0x70-0x7F | Passive Sensors | CANRec |

h2. CAN data structutre

|_. Size |_. Decription |_. Examples |
| 2 | Object | Plain Sensor value; Set illumination |
| 1 | Unit | hz, Float, Time, Date, Percent, promilPwm, centiCelsius, canId, room, Multipacket-String |
| 1 | Flags | Confirmation required |
| 4 | Value | 32Bit |

h2. Objects

|_. Code |_. Description |
| none | |
| ambientLight | |
| plantLight | |
| multimediaSwitch | |
| mainSwitch | |
| date | |
| time | |
| dummy | |
| plantSensor | |
| plantSensor [0-7] | |
| firmwareVersion | |
| firmwareDate | |
| hardwareRevision | |
| hardwareDate | |
| temperatureIntern [0-7] | |
| temperatureExtern [0-7] | |
| humidity | |
| VOC | |
| Replay | |
| Data-Dump (SD-Card) | |

h2. Units

* Date: year 2B, month 1B, day 1B
* Time: hour 1B, minute 1B, second 1B, subsecond 1B

h2. Example: Turn on the lights

|_.Data |_.Size |_.Description |
|0x300 | 29 Bits | Function code: Write Object; All objects. |
|0x0 | 2 Byte | Message-Type: Global command |
|0x1 | 1 Byte | Data-Type: PWM Permill |
|0x1 | 1 Byte | Flags: None |
|1000 | 4 Byte | Value: Full Brightness |

h1. Multipacket-Strings

There should be the posssibillity to write the complete SPI-Flash even if it takes forever.
Not every slave needs to be able to send super big blocks. But every slave should be able to
send e.g. descriptions.
There can not be multiple transfers at the same time from one node because there is no identification.

|_. Size |_. Type |
| 0x4 | Package number (0: Data contains package count) |
| 0x4 | Data |

h2. Header

|_. Size |_. Type |
| 0x4 | Total size |
| 0x4 | Type (1=SDCard) |
| 0x4 | Target node ID |
| 0x4 | CRC32 of data |

h2. Example: CANRec

PC requests an complete dump from single Node. Node will just stream it out.

h1. NMT

h2. Actuator introduction

When introduction is requested by system command, each device must send Its UID (function code "NMT introduce") and an description.

|_. Size |_. Decription |_. Examples |
| 2 | Object | Object |
| 6 | MAC/Unique ID| 48Bit |

h3. Objects

|_. Size |_. Decription |
|1 | Request intoruction |
|2 | MAC low |
|3 | MAC high |
|4 | Protocol versions |
|5 | Firmware version |
|6 | Product Code |
|7 | Node-Id |

h3. Protocol versions

|_. Size |_. Decription |
|1 | TDT Major |
|1 | TDT Minor |
|1 | NMT Major |
|1 | NMT Minor |
|1 | Blob Major |
|1 | Blob Minor |

h2. Usecase: Setting Node-ID

Two nodes may have the same Node-ID. When scanning the network, the nodes will overwrite the counterparts information.
The "NMT-Introduce"-function code is used by the nodes to send theyr complete UID. NMT can then send
The new NodeID can not be part of the CAN-ID because the device may be filtering it out. (The whole NMT )

h1. V2

|_. Size |_. Decription |_. Examples |
| 1 | Packet type | Standard TDT packet |
| 1 | Sub-Id; | Futher index; Sub-Sensor or more specifi kind of thing to be set |
| 1 | Data type | Int, Float, Time, Date, Percent, Promil, Multipacket-String |
| 1 | Unit | Hz, °C, Time, Date, PWM, CAN-ID, Name, Description, Room |
| 4 | Value | 32Bit |

h1. V3

|_. Size |_. Decription |_. Examples |
| 2 | Object | |
| 1 | Sub-Id; | Flags, Subid |
| 1 | Unit/Type | Hz_int, °C_centi, Time, Date, PWM_milli, CAN-ID, Name, Description, Room |
| 4 | Value | 32Bit |

h2. Flags

4 Bit multi message count
4 Bit multi message pos

Length in Bytes given via CAN?
Strings with max. 64 characters.

h2. Multimessage package

There should be the possibillity to write the complete SPI-Flash even if it takes forever.
Not every slave needs to be able to send super big blocks. But every slave should be able to
send e.g. descriptions.

h2. Alarms/Alerts

Devices should indicate issues; e.g.:

* Battery low
* I2C problems

h2. Object structutre

|_. Size |_. Decription |_. Examples |
| 2 | Object | I2C, VBat, |
| 1 | Unit | hz, Float, Time, Date, Percent, promilPwm, centiCelsius, canId, room, Multipacket-String |
| 1 | Issue | Whats wrong, Undervolts, Communication error |
| 4 | Value | 32Bit |