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ISO 9001 certified


embOS for ATMEL AVR / ATMega / ATXMega was developed for and with IAR's AVR compiler and supports the small data memory model offered by this compiler. It comes with an easy to use start workspace and start projects for IAR's embedded workbench.


Pricing Trial download Notification Subscribe to embOS software notification Release Notes


Resources and performance data

Memory usage
Kernel size (ROM) 1974 bytes
Kernel RAM usage 25 bytes
RAM usage per task control block 18 bytes
RAM usage per resource semaphore 6 bytes
RAM usage per counting semaphore 2 bytes
RAM usage per mailbox 8 bytes
RAM usage per software timer 8 bytes
RAM usage event 0 bytes
Min. stack-size per task (RAM) 100 bytes
Context switch time 346 clock cycles (49.4 µs), independent of number of tasks
Interrupt latency time Max. 168 clock cycles (24 µs)
Kernel CPU usage/TICK Less than 2% of total calculation time at 1000 Interrupts/second (1ms TICK)
Basic time unit (TICK) Typ. 1 ms, min. 50 µs (20 kHz interrupt frequency)
Max. no. of tasks Unlimited (by available RAM only)
Max. no. of mailboxes Unlimited (by available RAM only)
Max. no. of semaphores Unlimited (by available RAM only)
Max. no. of software timers Unlimited (by available RAM only)
Max. no. of priorities 255
Stack size idle task (RAM) 0 (no memory needed)
Nested interrupts Permitted
Task switches from within ISR Possible

Absolute timings given above were measured with embOS release build on an ATMega128 CPU running at 7.3728MHz.

Board support packages

embOS comes with lots of ready to go start projects and support packages for various AVR/ATMega CPUs and starterboards.

CPU Eval board
Atmel ATmega64 Atmel ATmega64 - STK500
Atmel ATmega103 Atmel ATmega103
Atmel ATmega128 Atmel ATmega128 - STK500
Atmel ATmega2561 Atmel ATmega2561
Atmel ATXmega128 Olimex AVRPX128A1