I applied through an employee referral.

Had three rounds of technical interview. Asked in-depth C, OS concepts and some of RTOS concepts, and discussed about projects. Then had an HR discussion. All the questions are counter to your answers.

C:

• Structure padding, packing
• 4 programs (reversing array, swapping bits, 2 array problems)
• Build process
• Storage classes
• Type qualifiers (volatile)
• Pointers
• DMA
• Program memory layout

OS:

• Process vs thread
• POSIX
• 1 threading code using mutex
• Critical section and race condition
• IPC and shared memory
• Interrupts

RTOS:

• Priority inheritance and inversion
• Discussions on FreeRTOS APIs