- A cross-compiler : [ARM-GCC (10.3-2021.10)](https://developer.arm.com/downloads/-/gnu-rm)
- The NRF52 SDK 15.3.0 : [nRF-SDK v15.3.0](https://developer.nordicsemi.com/nRF5_SDK/nRF5_SDK_v15.x.x/nRF5_SDK_15.3.0_59ac345.zip)
- The Python 3 modules `cbor`, `intelhex`, `click` and `cryptography` modules for the `mcuboot` tool (see [requirements.txt](../tools/mcuboot/requirements.txt))
- To keep the system clean, you can install python modules into a python virtual environment (`venv`)
**ARM_NONE_EABI_TOOLCHAIN_PATH**|path to the toolchain directory|`-DARM_NONE_EABI_TOOLCHAIN_PATH=/home/jf/nrf52/gcc-arm-none-eabi-10.3-2021.10/`|
**NRF5_SDK_PATH**|path to the NRF52 SDK|`-DNRF5_SDK_PATH=/home/jf/nrf52/Pinetime/sdk`|
**USE_JLINK, USE_GDB_CLIENT and USE_OPENOCD**|Enable *JLink* mode, *GDB Client* (Black Magic Probe) mode or *OpenOCD* mode (set the one you want to use to `1`)|`-DUSE_JLINK=1`
**CMAKE_BUILD_TYPE (\*)**| Build type (Release or Debug). Release is applied by default if this variable is not specified.|`-DCMAKE_BUILD_TYPE=Debug`
**NRFJPROG**|Path to the NRFJProg executable. Used only if `USE_JLINK` is 1.|`-DNRFJPROG=/opt/nrfjprog/nrfjprog`
**GDB_CLIENT_BIN_PATH**|Path to arm-none-eabi-gdb executable. Used only if `USE_GDB_CLIENT` is 1.|`-DGDB_CLIENT_BIN_PATH=/home/jf/nrf52/gcc-arm-none-eabi-9-2019-q4-major/bin/arm-none-eabi-gdb`
**GDB_CLIENT_TARGET_REMOTE**|Target remote connection string. Used only if `USE_GDB_CLIENT` is 1.|`-DGDB_CLIENT_TARGET_REMOTE=/dev/ttyACM0`
**BUILD_DFU (\*\*)**|Build DFU files while building (needs [adafruit-nrfutil](https://github.com/adafruit/Adafruit_nRF52_nrfutil)).|`-DBUILD_DFU=1`
**BUILD_RESOURCES (\*\*)**| Generate external resource while building (needs [lv_font_conv](https://github.com/lvgl/lv_font_conv) and [lv_img_conv](https://github.com/lvgl/lv_img_conv). |`-DBUILD_RESOURCES=1`
By default, this variable is set to *Release*. It compiles the code with size and speed optimizations. We use this value for all the binaries we publish when we [release](https://github.com/InfiniTimeOrg/InfiniTime/releases) new versions of InfiniTime.
The *Debug* mode disables all optimizations, which makes the code easier to debug. However, the binary size will likely be too big to fit in the internal flash memory. If you want to build and debug a *Debug* binary, you'll need to disable some parts of the code. For example, the icons for the **Navigation** app use a lot of memory space. You can comment the content of `m_iconMap` in the [Navigation](https://github.com/InfiniTimeOrg/InfiniTime/blob/develop/src/displayapp/screens/Navigation.h#L148) application to free some memory.
DFU files are the files you'll need to install your build of InfiniTime using OTA (over-the-air) mechanism. To generate the DFU file, the Python tool [adafruit-nrfutil](https://github.com/adafruit/Adafruit_nRF52_nrfutil) is needed on your system. Check that this tool is properly installed before enabling this option.
If you just want to build the project and run it on the Pinetime, using *pinetime-app* is recommended. See [this page](../bootloader/README.md) for more info about bootloader support.
These files are needed by the Pine64 factory to flash InfiniTime as the default firmware on the PineTimes.
Two files are needed: an **HEX (.hex)** file that contains the content of the internal flash memory (bootloader + InfiniTime) and a **binary (.bin)** file that contains the content of the external flash memory (recovery firmware).
where `bootloader.bin` is the [last stable version](https://github.com/JF002/pinetime-mcuboot-bootloader/releases) of the [bootloader](https://github.com/JF002/pinetime-mcuboot-bootloader).
where `pinetime-mcuboot-app-image-1.6.0.bin` is [the bin of the last MCUBoot image](https://github.com/InfiniTimeOrg/InfiniTime/releases) of [InfiniTime](https://github.com/InfiniTimeOrg/InfiniTime).
Pay attention to the parameter `--change-addresses 0x8000`. It's needed to ensure the image will be flashed at the offset expected by the bootloader (0x8000).
This file is the MCUBoot image of the last stable version of the recovery firmware. It must be flashed at offset **0x00** of the external SPINOR flash memory.