4.7.4.2.5 Software Reset

The RSTC offers commands to assert the different reset signals. These commands are performed by writing the Control register (RSTC_CR) with the following bits at ‘1’:

  • RSTC_CR.PROCRST: Writing a ‘1’ to PROCRST resets the processor and all the embedded peripherals, including the memory system and, in particular, the Remap Command.
  • RSTC_CR.EXTRST: Writing a ‘1’ to EXTRST asserts low the NRST_OUT pin during a time defined by the field RSTC_MR.ERSTL.

The Software reset is entered if at least one of these bits is written to ‘1’ by the software. All these commands can be performed independently or simultaneously. The Software reset lasts three MD_SLCK cycles.

The internal reset signals are asserted as soon as the register write is performed. They are released when the Software reset has ended, i.e., synchronously to MD_SLCK.

If EXTRST is written to ‘1’, the NRST_OUT pin is asserted depending on the configuration of RSTC_MR.ERSTL. However, the resulting falling edge on NRST_OUT does not lead to a User reset.

If and only if the RSTC_CR.PROCRST is written to ‘1’, the RSTC reports the software status in field RSTC_SR.RSTTYP. Other software resets are not reported in RSTTYP.

As soon as a software operation is detected, RSTC_SR.SRCMP is written to ‘1’. SRCMP is cleared at the end of the Software reset. No other Software reset can be performed while SRCMP=‘1’, and writing any value in the RSTC_CR has no effect.

Figure 4-22. Software Reset Timing Diagram (PROCRST)