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102
T48C862-R4 [Preliminary]
4551C–4BMCU–01/04
Components of MARC4 Core ............................................................ 14
Program Memory................................................................................................ 14
RAM.................................................................................................................... 15
Expression Stack ..........................................................................................15
Return Stack .................................................................................................15
Registers............................................................................................................. 16
Program Counter (PC) ..................................................................................16
RAM Address Registers ................................................................................17
Expression Stack Pointer (SP) ......................................................................17
Return Stack Pointer (RP) ............................................................................17
RAM Address Registers (X and Y) ...............................................................17
Top of Stack (TOS) .......................................................................................17
Condition Code Register (CCR) ....................................................................17
Carry/Borrow (C) ...........................................................................................17
Branch (B) .....................................................................................................17
Interrupt Enable (I) ........................................................................................17
ALU..................................................................................................................... 18
I/O Bus................................................................................................................ 18
Instruction Set..................................................................................................... 18
Interrupt Structure............................................................................................... 18
Interrupt Processing ......................................................................................19
Interrupt Latency ...........................................................................................19
Software Interrupts ............................................................................................. 20
Hardware Interrupts............................................................................................ 20
Master Reset ....................................................................................... 21
Power-on Reset and Brown-out Detection ......................................................... 21
Watchdog Reset ...........................................................................................22
External Clock Supervisor .............................................................................22
Voltage Monitor................................................................................... 22
Voltage Monitor Control/Status Register .......................................................23
Clock Generation................................................................................ 24
Clock Module...................................................................................................... 24
Oscillator Circuits and External Clock Input Stage............................................. 25
RC-oscillator 1 Fully Integrated .....................................................................25
External Input Clock ......................................................................................26
RC-oscillator 2 with External Trimming Resistor ...........................................26
4-MHz Oscillator ...........................................................................................27
32-kHz Oscillator ...........................................................................................27
Clock Management............................................................................................. 28
Clock Management Register (CM) ................................................................28
System Configuration Register (SC) .............................................................29
Power-down Modes............................................................................ 29