R7FA4M2 Multi-Click Smartwatch Example

This project was done using NECTOStudio IDE.

This bare-metal example turns a Clicker 4 for R7FA4M2A board into a small smartwatch-style demo. It combines a real-time clock using RTC 14 Click, environmental sensing through Temp&Hum 27 Click, graphics on IPS Display 2 Click, stopwatch control through push buttons, and remote BLE control using BLE Tiny Click with Renesas CodeLess / SmartConsole.

Visualization

• The smartwatch dashboard on the first screen shows:
  • HH:MM time with AM/PM or 24-hour mode,
  • temperature and humidity summary cards,
  • day of the week,
  • full date.
• The dedicated Environment screen keeps the animated thermometer and filling humidity droplet.
• The dedicated Time of Day screen now uses the title "TIME OF DAY".
• The sun and moon follow a lower trajectory that remains inside the visible sky scene instead of approaching the header.
• The sun/moon position is recalculated from RTC time and changes once per minute.
• Physical B3 now cycles through four screens, while BLE still uses separate trigger numbers and reserves B3 for stopwatch stop/reset.
• An optional compile-time demonstration mode can generate the same B3 action automatically every 15 seconds.
• Missing source-level Doxygen comments have been added, and a ready-to-use Doxyfile is included.

Features

• Four-screen smartwatch UI:
  1. Smartwatch Dashboard — time, weekday, date, temperature and humidity summary.
  2. Environment — animated temperature and humidity widgets.
  3. Time of Day — RTC time with lower sun/moon sky trajectory.
  4. Stopwatch — start, pause, continue, stop and reset.
• Animated thermometer level and temperature-dependent color.
• Animated humidity droplet with water level based on relative humidity.
• RTC-based day/night visualization with transparent sun/moon rendering.
• Sun/moon position updated once per RTC minute.
• BLE connected/disconnected status indicator on every screen.
• Millisecond stopwatch with background counting.
• Physical interrupt controls through P304/IRQ9 and P111/IRQ4.
• Separate BLE/SmartConsole commands for screen selection and stopwatch control.
• RTC date/time synchronization through a pipe-separated CodeLess memory command.
• Cooperative foreground loop; ISRs only acknowledge hardware and update small state flags/counters.
• Optional automatic screen demonstration using the existing physical B3 state-machine path.
• Doxygen comments for public APIs, internal helpers, interrupt handlers and configuration groups.

Hardware and peripheral assignment

mikroBUS socket	Click board	MCU peripheral	Main pins	Purpose
1	BLE TINY Click	SCI3 UART, 57,600 baud	P408 RX, P409 TX, P211 RST	CodeLess connection status, RTC synchronization, remote screen selection and remote stopwatch control
2	IPS Display 2 Click	SCI0 simple SPI, 5 MHz	P410 MISO, P411 MOSI, P412 SCK, P708 CS, P415 DC, P210 RST, P001 backlight	240 × 240 smartwatch UI
3	RTC 14 Click	IIC0, 100 kHz	P400 SCL, P401 SDA, P610 EIN	Date and time source
4	Temp&Hum 27 Click	IIC0, 100 kHz	P400 SCL, P401 SDA, P105 enable, P101 alert	Temperature and relative-humidity measurements

RTC 14 and Temp&Hum 27 intentionally share IIC0. Their 7-bit addresses are different (0x6F and 0x54), so both devices can use P400/P401 simultaneously.

Interrupt allocation

Source	Event	ICU/NVIC slot	Priority	Role
AGT0 underflow	0x040	15	12	1 ms system tick and stopwatch timebase
P304 / IRQ9	0x00A	16	6	B3: physical screen cycle or stopwatch reset
P111 / IRQ4	0x005	17	6	B4: stopwatch start, pause and continue
SCI3 RXI	0x192	18	5	Store BLE UART bytes in the receive ring buffer
SCI3 ERI	0x195	19	5	Clear SCI errors and preserve a pending byte

The active vector table is copied to aligned RAM and only the required entries are replaced. This preserves the UART vectors already supplied by the surrounding NECTO project.

Screen behavior

Screen 1 — Smartwatch Dashboard

The restored first screen contains:

• HH:MM time,
• AM/PM or 24-hour indicator,
• compact temperature and humidity values,
• day of the week,
• date,
• BLE status indicator.

Screen 2 — Environment

This screen contains only environmental information:

• temperature value,
• animated thermometer,
• temperature color transition from blue to red,
• humidity value,
• animated water droplet,
• BLE status indicator.

Screen 3 — Time of Day

This screen contains only time-of-day information:

• header text TIME OF DAY,
• digital RTC time,
• daytime sky with the sun or nighttime sky with the moon,
• a lowered trajectory that keeps the celestial body inside the sky area,
• sun/moon position updated once every minute,
• BLE status indicator.

Screen 4 — Stopwatch

This screen contains only stopwatch information:

• elapsed time in hours, minutes, seconds and milliseconds,
• status (READY, RUNNING, PAUSED),
• B4 action hints,
• B3 behavior hint,
• BLE status indicator.

Physical button behavior

B3 — P304 / IRQ9

Physical B3 is now dedicated to screen cycling with one exception.

• From Smartwatch Dashboard: go to Environment.
• From Environment: go to Time of Day.
• From Time of Day: go to Stopwatch.
• From Stopwatch at 00:00:00.000: go to Smartwatch Dashboard.
• From Stopwatch while running or while the elapsed value is nonzero: stop and reset the stopwatch to zero, and stay on the stopwatch screen.

This means physical B3 does not jump back from the stopwatch to the main screen until the stopwatch is already reset to zero.

B4 — P111 / IRQ4

Physical B4 controls only the stopwatch while the stopwatch screen is active:

• Ready at zero: start.
• Running: pause.
• Paused: continue.
• On other screens: no stopwatch state change.

Automatic 15-second screen demonstration

Automatic screen cycling is disabled by default. To enable it, edit include/app_config.h and change one macro:

#define APP_AUTO_B3_DEMO_ENABLED            (true)

When enabled, the application queues the same B3 action used by the physical P304/IRQ9 button every 15 seconds. The sequence is therefore:

Smartwatch Dashboard -> Environment -> Time of Day -> Stopwatch -> Smartwatch Dashboard

The implementation does not maintain a second navigation state machine. Automatic mode sets the normal app_physical_b3_pending flag, so button and automatic behavior remain identical. Every processed manual or automatic B3 action restarts the 15-second interval.

If the stopwatch is running or contains a nonzero value when an automatic B3 action occurs, the normal B3 rule still applies: the stopwatch is stopped and reset first, and the screen remains on the stopwatch until the following B3 action.

To return to manual-only operation, set the macro back to false.

BLE / SmartConsole behavior

BLE navigation is intentionally separated from the physical-button behavior.

• STOPWATCH|B1 → show Smartwatch Dashboard.
• STOPWATCH|B2 → show Environment.
• STOPWATCH|B3 → stop and reset the stopwatch and show the stopwatch screen.
• STOPWATCH|B4 → show the Stopwatch screen and toggle start/pause/continue.
• STOPWATCH|B5 → show Time of Day.

This keeps BLE B3 dedicated to stopping/resetting the stopwatch, while physical B3 remains the screen-cycle button.

SmartConsole commands

SmartConsole stores commands in CodeLess memory slot 0. The firmware reads the slot every 200 ms while connected and replaces a successfully processed command with EMPTY.

Set RTC date and time

AT+MEM=0,RTC|YYYY|MM|DD|HH|MM|SS|WEEKDAY

Example:

AT+MEM=0,RTC|2026|07|13|15|57|00|1

HH is a 24-hour value. Weekday numbering is 0 = Sunday through 6 = Saturday.

Show the Smartwatch Dashboard

AT+MEM=0,STOPWATCH|B1

Show the Environment screen

AT+MEM=0,STOPWATCH|B2

Show the Time of Day screen

AT+MEM=0,STOPWATCH|B5

Stop and reset the stopwatch

AT+MEM=0,STOPWATCH|B3

Show or control the stopwatch

AT+MEM=0,STOPWATCH|B4

When SmartConsole's AT+ prefix option is enabled, enter only the part beginning with MEM=.... SmartConsole automatically converts local commands to the remote ATr... form.

Demo: physical screen cycling

The first GIF shows the local B3/B4 control path and the four-screen navigation. P304 generates IRQ9 for B3 actions, while P111 generates IRQ4 for B4 actions. When APP_AUTO_B3_DEMO_ENABLED is true, the same sequence can be demonstrated without pressing B3 because the firmware queues B3 every 15 seconds.

Demo: control through Bluetooth

The second GIF shows remote control through BLE Tiny Click and SmartConsole. BLE uses dedicated screen commands, while STOPWATCH|B3 remains reserved for stopping and resetting the stopwatch.

Project structure

.
├── README.md
├── CMakeLists.txt
├── Doxyfile
├── include
│   ├── app_config.h
│   ├── app_controller.h
│   ├── app_interrupts.h
│   ├── app_types.h
│   ├── bletiny.h
│   ├── iic0_bus.h
│   ├── ips2_display.h
│   ├── project_platform.h
│   ├── ra4m2_baremetal.h
│   ├── rtc14.h
│   └── temphum27.h
└── src
    ├── app_controller.c
    ├── app_interrupts.c
    ├── bletiny.c
    ├── iic0_bus.c
    ├── ips2_display.c
    ├── main.c
    ├── rtc14.c
    └── temphum27.c

Module responsibilities

• app_controller: owns visible screen, stopwatch state, pending actions and foreground scheduling.
• app_interrupts: installs RAM vectors and configures AGT0, IRQ9 and IRQ4.
• iic0_bus: shared polling IIC0 master implementation.
• rtc14: RTC validation, BCD conversion, read/write and logging.
• temphum27: sensor reset, measurement, CRC and fixed-point conversion.
• ips2_display: SCI0 SPI transport, display initialization, drawing primitives, caching and all four smartwatch UI screens.
• bletiny: SCI3 UART, ring buffer, CodeLess parsing, BLE state and SmartConsole commands.

Integration notes

1. Clone this repo to you PC.
2. Open NECTOStudio IDE.
3. Create Configuration for Clicker 4 for R7FA4M2A Board.
4. Update Terget connection parameters to be as on this image:
5. Open cloned repo as a project in NECTOStudio IDE and select created Configuration.
6. Connect USB-C cable to your Clicker 4 for R7FA4M2A Board and program it.
7. Use Renesas CodeLess / SmartConsole or Buttons B3/B4 to control the application flow.

Documentation

The project includes Doxygen-style comments for public declarations, internal helper functions, interrupt handlers, shared data types and configuration groups. Static functions are included in the generated output.

The generated documentation is written to:

docs/html/index.html