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ISO 9001 certified

78K4 series, IAR

embOS for NEC 78K4 series was developed for and with IAR's compiler and by now supports the large memory model offered by this compiler. It comes with an easy to use start project for IAR's embedded workbench. Software development with NEC debugger, simulator and CSpy simulator is supported.


Pricing Trial download Notification Subscribe to embOS software notification Release Notes


Resources and performance data

Memory usage
Kernel size (ROM) 1401 bytes
Kernel RAM usage 31 bytes
RAM usage per task control block 22 bytes
RAM usage per resource semaphore 5 bytes
RAM usage per counting semaphore 2 bytes
RAM usage per mailbox 12 bytes
RAM usage per software timer 11 bytes
RAM usage event 0 bytes
Min. stack-size per task (RAM) 120 bytes
Context switch time 142 µs, independent of number of tasks
Interrupt latency time Better 56 µs
Kernel CPU usage/TICK Less than 1% of total calculation time at 1000 interrupts/second (1ms TICK)
Basic time unit (TICK) Typ. 1 ms, min. 100 µs (10 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 78K4 CPU running at 16MHz in LARGE memory model.


Board support packages

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

CPU Eval board
Renesas 78403 Renesas 78403 evalboard