High Side Driver for the Mercury System

• User LED: by default it is set to work in heartbeat LED mode (periodic pulses).
• Mercury Connector: used to interface with the other boards of the Mercury system.
• Address Dip Switch: to set the board address within the Mercury system.
• Programmer Connector: Microchip PicKit 3 programmer/debugger connector. It connects straight to the debug port of the microcontroller, to allow advanced debugging and programming.
• HSDs Status LEDs: show the state of the HSD channel (ON or OFF).
• Power Source Sel. Jumper: jumper for selecting the power source: internal (Vbat) or external (pins of the HSD output connectors).

• Timer: 4 x 8-bit, 1 x 16-bit
• ADC: 12 ch, 10-bit
• Comparators: 2
• Temperature range: -40°C ~ 125°C
• Operating voltage: 1.8~5.5 V
• Pin Count: 20
• XLP: yes

The set of boards that makes up the Mercury System is organised into the following “families”:

• Base Board (BB): It is the “brain” of the whole Mercury System and holds the main logic unit, several communication buses and the connectors for interfacing the slaves. It also has a simple power supply and a charger for a single LiPo cell (enough for the power needs of simpler systems). It comes in different variants, depending on the microcontroller unit used.

• Modem Board (MB): this is the board that provides network connectivity. It comes in different variants, depending on the network interface (GSM / GPRS, Wi-Fi, BT, Radio and so on). It is interfaced to the base board over a dedicated serial line.

• Power Board (PB): this is the board that meets the particular power needs of the system, where required. They vary according to the power need to be met (high power, solar harvesting, piezoelectric harvesting and so on).

• Slave Board (SB): these are the peripherals of the system and they vary with the specific sensor or actuator fitted. Typical examples are SBs with relays, temperature sensors, RGB LED controllers, servo controllers, accelerometers and so on. They talk to the BB over I2C or UART with a dedicated command set.

• Expansion Board (EB): these are the boards that allow Mercury boards to be connected side by side. Some variants can carry a display, a battery holder and so on.

• Brain-Less Board (BL): these are the boards with no controller. In general they carry very simple sensors or actuators that do not need the bus interface. They are an alternative to slave boards for applications that have to keep costs down.

Slave Boards and Modem Boards come pre-programmed with firmware implementing a dedicated command set for high level control, while Base Boards carry a software framework that provides all the low level services (operating system, peripheral drivers, system services and so on), leaving the user only the application level logic to develop. 

HAL (Hardware Abstraction Layer): the purpose of this layer is to abstract the hardware dependencies away from the upper layers.
SML (System Management Layer): the purpose of this layer is to provide services for managing the communication buses (I2C, UART) and the Modem Board (WiFi, BT, GSM / GPRS). It also provides a set of system services such as System Power Management, RTCC, USB terminal and so on.
It is split into two main components:

• PML: peripheral management layer
• SSL: system services layer

OSL (Operative System Layer): this layer is a lightweight RTOS providing basic services to the system, such as scheduling tables for the various tasks, events, SW timers, alarms and so on.

There are several sub-families of Slave Board:

• Sensor Slave Board
• Actuator Slave Board
• Communication Slave Board
• Interface Slave Board
• Special Slave Boards

The table below gives some examples for each sub-family:

• Mercury System Getting Started Guide IoT and Connectivity Made Simple
• Slave FW Upgrade Package
• FW Package
• MS_SB140_Datasheet
• MS_SB140_Schematic