This directory contains external library code.

The cmsis directory contains code from:
  https://github.com/ARM-software/CMSIS_5
version 5.3.0 (49ac527aa7406cecbba46d4d3bdbc7f60c6c6d42). Contents
taken from the CMSIS/Core/Include/ directory.

The sam3x directory contains code from the
Atmel.SAM3X_DFP.1.0.50.atpack zip file found at:
  http://packs.download.atmel.com/
version 1.0.50 (extracted on 20180725).

The sam4e directory contains code from the
Atmel.SAM4E_DFP.1.1.57.atpack zip file found at:
  http://packs.download.atmel.com/
version 1.1.57 (extracted on 20180806). It has been modified to fix
some AFEC register RW accesses. See sam4e.patch for the modifications.

The sam4s directory contains code from the
Atmel.SAM4S_DFP.1.0.56.atpack zip file found at:
  http://packs.download.atmel.com/
version 1.0.56 (extracted on 20181220).

The samd21 directory contains code from the
Atmel.SAMD21_DFP.1.3.304.atpack zip file found at:
  http://packs.download.atmel.com/
version 1.3.304 (extracted on 20180725).

The samd51 directory contains code from the
Atmel.SAMD51_DFP.1.1.96.atpack zip file found at:
  http://packs.download.atmel.com/
version 1.1.96 (extracted on 20190110).

The lpc176x directory contains code from the mbed project:
  https://github.com/ARMmbed/mbed-os
version mbed-os-5.8.3 (c05d72c3c005fbb7e92c3994c32bda45218ae7fe).
Contents taken from the targets/TARGET_NXP/TARGET_LPC176X/ directory.
It has been modified to set the appropriate clock speeds on the
LPC1768 and LPC1769. See lpc176x.patch for the modifications.

The stm32f0 directory contains code from STMicroelectronics:
  http://www.st.com/en/embedded-software/stm32cubef1.html
version 1.10.0 (extracted 20190721).

The stm32f1 directory contains code from STMicroelectronics:
  http://www.st.com/en/embedded-software/stm32cubef1.html
version 1.8.0 (extracted 20190721).

The stm32f2 directory contains code from STMicroelectronics:
  https://www.st.com/content/st_com/en/products/embedded-software/mcu-mpu-embedded-software/stm32-embedded-software/stm32cube-mcu-mpu-packages/stm32cubef2.html
version 1.9.0 (extracted 20200614).

The stm32f4 directory contains code from STMicroelectronics:
  http://www.st.com/en/embedded-software/stm32cubef4.html
version 1.24.0 (extracted 20190723).

The hub-ctrl directory contains code from:
  https://github.com/codazoda/hub-ctrl.c/
revision 42095e522859059e8a5f4ec05c1e3def01a870a9.

The bossac directory contains code from:
  https://github.com/shumatech/BOSSA
version 1.9 (b176eeef918fc810045c832348590595120187b4).

The hidflash directory contains code from:
  https://github.com/Serasidis/STM32_HID_Bootloader
version 2.2.2 (2ab7927a27b7b78ef730782ea5f9b5d2c8f34671). It has been
modified to work with Klipper - see hidflash/README for the
details. See changes.diff for the modifications.

The pru_rpmsg directory contains code from:
  https://github.com/dinuxbg/pru-gcc-examples
revision 425a42d82006cf0aa24be27b483d2f6a41607489. The code is taken
from the repo's hc-sr04-range-sensor directory. It has been modified
so that the IEP definitions compile correctly. See pru_rpmsg.patch for
the modifications.
