SAMD21 HAL

Hardware Abstraction Layer for SAMD21 microcontrollers.

Integration

The library can be included as a submodule or via CPM.cmake, in either case the master branch can be used.

A total of 5 interface targets are registered all of which should be linked to a target.

• cmsis: includes the CMSIS header files
• atsamd21e18a-dfp: microcontroller specific registers
• samd21-hal-api: library's header files
• samd21-hal-sources: library's source code
• samd21-hal-options: recommended compilation and linker flags

Example

include(tools/cmake/CPM.cmake)
CPMAddPackage("gh:c4deszes/samd21-hal#master")

add_executable(MyApp src/main.c)
target_link_libraries(MyApp PUBLIC  cmsis
                                    atsamd21e18a-dfp
                                    samd21-hal-api
                                    samd21-hal-sources
                                    samd21-hal-options)

Peripherals

Name	Abbreviation	Status
Analog Comparator	AC	Non functional
Analog-to-Digital Converter	ADC	Non-functional
Digital-to-Analog Converter	DAC	Not implemented
Direct Memory Access Controller	DMAC	Not implemented
Device Signature Unit	DSU	Only supports CRC and Serial number
External Interrupt Controller	EIC	Non functional
Event System	EVSYS	No interrupt support
Generic Clock Controller	GCLK	Complete
I/O Pin Controller	GPIO	Complete
Inter-IC Sound Controller	I2S	Not implemented
Nonvolatile Memory Controller	NVMCTRL	No interrupts, no locking
Peripheral Touch Controller	PTC	Not implemented
Power Manager	PM	No interrupt support, cannot control all peripherals
Real Time Clock	RTC	Non functional
SERCOM USART	SERCOM_USART	Only supports async mode, fixed 8/N/1
SERCOM SPI	SERCOM_SPI	Not implemented
SERCOM I2C	SERCOM_I2C	Not implemented
System Controller	SYSCTRL	Only supports DFLL, OSC8M, OSC32K
Timer Counter	TC	Only supports capture mode
Timer Counter for Control	TCC	Only supports basic count up to period and interrupt
USB Controller	USB	Not implemented
Watchdog	WDT	No windowed mode support

Components

• NVIC: enables interrupts
• Startup: initializes the zero section, sets the vector table pointer
• Ringbuffer: implements ringbuffers for 8, 16 and 32 bit unsigned integers
• Software Timer: implements a count down mechanism
• Scheduler: implements a round robin scheduler