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ISO 9001 certified


embOS for Renesas R8C was developed for and with Renesas' HEW for R8C and supports all memory models offered by this compiler. It comes with an easy to use start project for HEW embedded workbench. Software development with Renesas' emulator is supported.


Pricing Trial download Notification Subscribe to embOS software notification Release Notes


Resources and performance data

Memory usage
Kernel size (ROM) 1281 bytes
Kernel RAM usage 28 bytes
RAM usage per task control block 18 bytes
RAM usage per resource semaphore 4 bytes
RAM usage per counting semaphore 2 bytes
RAM usage per mailbox 12 bytes
RAM usage per software timer 12 bytes
RAM usage event 0 bytes
Min. stack-size per task (RAM) 42 bytes
Context switching time 437 clock cycles (21.85 µs), independent of number of tasks
Interrupt latency time TBD
Kernel CPU usage/TICK Less than .4% of total calculation time at 1000 interrupts/second (1ms TICK)
Basic time unit (TICK) Typ. 1 ms, min. 20 µs (50 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 R8C/1B CPU running at 20MHz in NEAR memory model.


Board support packages

embOS comes with lots of ready to go start projects and support packages for various Renesas R8C CPUs and starterboards.

CPU Eval board
Renesas R8C23 Renesas RSKR8C23