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Both sides previous revision Previous revision Next revision | Previous revision | ||
en:calaos_io_controller [2015/08/21 20:05] nico [Calaos PLC IO] |
en:calaos_io_controller [2015/12/30 19:49] freebzh [Calaos PLC IO] |
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Calaos IO is currently in design phase, and it's far to be complete. The following page aims to describes what Calaos IO will be. | Calaos IO is currently in design phase, and it's far to be complete. The following page aims to describes what Calaos IO will be. | ||
- | Calaos IO is a board designed to controlled | + | Calaos IO is a board designed to control |
The spectifications are the following : | The spectifications are the following : | ||
Line 20: | Line 20: | ||
LEDs indicator? | LEDs indicator? | ||
+ | Schematics can be found here : https:// | ||
==== Bus ==== | ==== Bus ==== | ||
- | RS485 will be used as the principal bus to control the IOs on the board | + | RS485 will be used as the principal bus to control the IOs on the board. The components needed to use the bus are really cheap and the bus can withstand really long lines. |
==== Hardware ==== | ==== Hardware ==== | ||
The hardware is designed arround a tiny microcontroller. | The hardware is designed arround a tiny microcontroller. | ||
- | The folling | + | The following |
- STM32F0 (1,40€) | - STM32F0 (1,40€) | ||
- ATMEGA328 (3,20€) | - ATMEGA328 (3,20€) | ||
- | The IO are drived by a 2 GPIO exapanders | + | The IO are drived by a 2 GPIO expanders |
- PCA9505 is a gpio expander with 40 IOs | - PCA9505 is a gpio expander with 40 IOs | ||
Line 54: | Line 56: | ||
Modbus has the inconvenient of having a big overhead per packet and is used in systeme where the master need to access content of register of slaves. It's not designed with firmware upgrade of slaves in mind for example. | Modbus has the inconvenient of having a big overhead per packet and is used in systeme where the master need to access content of register of slaves. It's not designed with firmware upgrade of slaves in mind for example. | ||
+ | The frames will have the following format: | ||
+ | |||
+ | {{: | ||
+ | |||
+ | * Slave ID is a configurable id (through DIP switch or jumper) located on each sensors. | ||
+ | * The content is then application defined | ||
+ | |||
+ | {{: | ||
+ | |||
+ | |||
+ | {{: | ||
+ | |||
+ | === Informations === | ||
+ | |||
+ | Schematic and prototyping code can be found at https:// | ||
+ | Application note for reading RS485 bus with STM32 processors : | ||
+ | http:// | ||