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ISO 9001 certified


embOS for RENESAS RL78 was developed for and with IARs Embedded Workbench and compiler.
It supports all memory models offered by this compiler. It comes with easy to use start projects.


Pricing Trial download Notification Subscribe to embOS software notification Release Notes


Resources and performance data

Memory usage
Kernel size (ROM) Approx. 1500 bytes
Kernel RAM usage 45 bytes
RAM usage per task control block 14 bytes
RAM usage per resource semaphore 8 bytes
RAM usage per counting semaphore 4 bytes
RAM usage per mailbox 14 bytes
RAM usage per software timer 10 bytes
RAM usage event 0 bytes
Min. stack-size per task (RAM) 14 bytes
Context switch time 7.9 µs, independent of number of tasks
Interrupt latency time Zero
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. 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 values given above were measured with embOS XRrelease build on an RL78G13 CPU running at 32MHz.

Board support packages

embOS comes with lots of ready to go start projects and support packages for various RL78 CPUs and starterboards.

CPU Eval board
Renesas RL78G13 Glyn EVBRL78G13 Carrier
Renesas RL78G14 Renesas YRDKRL78G14
Renesas RL78G1A Renesas 78G1A starter board
Renesas RL78G1C Renesas RSKRL78G1C
Renesas RL78L12 Renesas RSKRL78L12
Renesas RL78L13 Renesas RSKRL78L13
Renesas RL78G13 Renesas YRPBRL78G13