uPD789074 Subseries 8-Bit Single-Chip Microcontrollers UD - Home

CHAPTER 12 RESET FUNCTIONTable 12-1. Status of Hardware After ResetHardwareStatus After ResetProgram counter (PC) Note 1Stack pointer (SP)Program status word (PSW)RAMLoaded with the contents ofthe reset vector table(0000H, 0001H)Undefined02HData memory Undefined Note 2General-purpose registers Undefined Note 2Ports (P0 to P3) (output latch)Port mode registers (PM0 to PM3)Pull-up resistor option registers (PU0, PUB2)Processor clock control register (PCC)Oscillation stabilization time selection register (OSTS)00HFFH00H02H04H16-bit timer8-bit timer/event counterWatchdog timerSerial interfaceInterruptsTimer counter (TM90)Compare register (CR90)Mode control register (TMC90)Capture register (TCP90)Buzzer output control register (BZC90)Timer counter (TM80)Compare register (CR80)Mode control register (TMC80)Clock selection register (WDCS)Mode register (WDTM)Serial operation mode register (CSIM20)Asynchronous serial interface mode register (ASIM20)Asynchronous serial interface status register (ASIS20)Baud rate generator control register (BRGC20)Transmit shift register (TXS20)Receive buffer register (RXB20)Request flag registers (IF0, IF1)Mask flag registers (MK0, MK1)External interrupt mode register (INTM0)0000HFFFFH00HUndefined00H00HUndefined00H00H00H00H00H00H00HFFHUndefined00HFFH00HNotes 1. While a reset signal is being input, and during the oscillation stabilization period, the contents of the PCwill be undefined, while the remainder of the hardware will be the same as after the reset.2. In standby mode, the RAM enters the hold state after a reset.User’s Manual U14801EJ3V1UD 173