STM8S903K3T6CTRSTM32F101VGT6 托盘

Registers The 8032 has several registers; these are the Pro- gram Counter (PC), Accumulator (A), B Register (B), the Stack Pointer (SP), the Program Status Word (PSW), General purpose registers (R0 to R7), and DPTR (Data Pointer register). Accumulator. The Accumulator is the 8-bit gen- eral purpose register, used for data operation such as transfer, temporary saving, and conditional tests. The Accumulator can be used as a 16-bit register with B Register as shown in Figure 6. B Register. The B Register is the 8-bit general purpose register, used for an arithmetic operation such as multiply, division with the Accumulator (see Figure 7). Stack Pointer. The Stack Pointer Register is 8 bits wide. It is incremented before data is stored during PUSH and CALL executions. While the stack may reside anywhere in on-chip RAM, the Stack Pointer is initialized to 07h after reset. This causes the stack to begin at location 08h (see Fig- ure 8). Program Counter. The Program Counter is a 16- bit wide which consists of two 8-bit registers, PCH and PCL. This counter indicates the address of the next instruction to be executed. In RESET state, the program counter has reset routine address (PCH:00h, PCL:00h). Program Status Word. The Program Status Word (PSW) contains several bits that reflect the current state of the CPU and select Internal RAM (00h to 1Fh: Bank0 to Bank3). The PSW is de- scribed in Figure 9, page 19. It contains the Carry Flag, the Auxiliary Carry Flag, the Half Carry (for BCD operation), the general purpose flag, the Register Bank Select Flags, the Overflow Flag, and Parity Flag. [Carry Flag, CY]. This flag stores any carry or not borrow from the ALU of CPU after an arithmetic operation and is also changed by the Shift Instruc- tion or Rotate Instruction. [Auxiliary Carry Flag, AC]. After operation, this is set when there is a carry from Bit 3 of ALU or there is no borrow from Bit 4 of ALU. [Register Bank Select Flags, RS0, RS1]. This flags select one of four bank(00~07H:bank0, 08~0Fh:bank1, 10~17h:bank2, 17~1Fh:bank3) in Internal RAM. [Overflow Flag, OV]. This flag is set to