9.8.2 System Background Debug Force Reset Register (SIM_SBDFR)This register contains a single write-only control bit. A serial background command suchas WRITE_BYTE must be used to write to SIM_SBDFR. Attempts to write this registerfrom a user program are ignored. Reads always return 0x00.NOTEThis register is the same as the BDC_SBDFR.Address: 1800h base + 1h offset = 1801hBit 7 6 5 4 3 2 1 0Read 0 0Write BDFRReset 0 0 0 0 0 0 0 0SIM_SBDFR field descriptionsField Description7–1ReservedThis field is reserved.This read-only field is reserved and always has the value 0.0BDFRBackground Debug Force ResetA serial background command such as WRITE_BYTE may be used to allow an external debug host toforce a target system reset. Writing logic 1 to this bit forces an MCU reset. This bit cannot be written froma user program.NOTE: BDFR is writable only through serial background debug commands, not from user programs.9.8.3 System Device Identification Register: High (SIM_SDIDH)This read-only register, together with SDIDL, is included so that host developmentsystems can identify the HCS08 derivative and revision number. This allows thedevelopment software to recognize where specific memory blocks, registers, and controlbits are located in a target MCU.Address: 1800h base + 2h offset = 1802hBit 7 6 5 4 3 2 1 0Read Reserved IDWriteReset 0 0 0 0 0 0 0 0Chapter 9 System Integration Module (SIM)MC9S08SU16 Reference Manual, Rev. 5, 4/2017NXP Semiconductors 107
