# RTOS errors

The following table lists the RTOS errors:

Error name | Hex | Description | Category
--- | --- | --- | ---
RTOS_ERROR_OUT_OF_MEMORY | 0xFFFFFFFE | No available board memory. | 3
RTOS_ERROR_DATA_ABORT | 0xFFFFFFFD | Fatal board error. Unaligned data access. | 3
RTOS_ERROR_INSTRUCTION_ABORT | 0xFFFFFFFC | Fatal board error. Unaligned instruction access. | 3
RTOS_ERROR_PURE_VIRTUAL_CALL | 0xFFFFFFF4 | C++ pure virtual call detected. | 3
RTOS_ERROR_MAILBOX_FULL | 0xFFFFFFF5 | Mailbox is full. (PacketMedia HMP only.) | 3
RTOS_ERROR_UNDEFINED_INSTRUCTION | 0xFFFFFFF7 | Fatal board error. Undefined instruction. | 3
RTOS_ERROR_TOO_MANY_THREADS | 0xFFFFFFF8 | Thread limit exceeded. | 3
RTOS_ERROR_MEMORY_ALREADY_FREE | 0xFFFFFFF9 | Board memory already freed. | 3
RTOS_ERROR_HOST_OS_ERROR | 0x0001 | Host operating system error. (PacketMedia HMP only.) | 3
RTOS_SHUTTING_DOWN | 0x9999 | RTOS has detected a fatal error and is shutting down. | 3