Hard Resetting the SPU

Issuing the RS command causes the AP to reset the entire SPU, halting all processing and I/O activity with the exception of itself and a few operations that must maintain state even over resets. The AP clears all data from the standard output (SO) and data processing first-in-first-out (DP FIFO) buffers. When the first character arrives from either buffer, the AP returns the console from control mode to console mode.

	NOTE: The AP command interpreter is active during the period between command execution and the arrival of characters (on either buffer ports) from the system, though the control mode prompt (CM>) isn't available.

Executing this command generates messages and prompts essential to resetting the system.

If the AP command interpreter encounters errors or inappropriate input during the reset (RS) process, it may display a combination of the following messages:

   Expecting "Y" or "N" (APERR 11)



   Unable to verify assertion of RESET_SYS backplane

   signal (APERR 01).



   RESET SYS backplane signal asserted, but unable to

   verify SPU deassertion of PPON backplane

   signal (APERR 02).



   PPON not reasserted by SPU after RESET_SYS

   deassertion (APERR 03).

The last three messages appear as a result of certain failures detected by the AP during the reset process. These messages are key to isolating the cause of the failure of the failed field-replaceable unit.

Once the reset is complete, the system displays the following message:

   SPU hardware was successfully reset. (APMSG 02)