UPSD3354DV-40U6 Datasheet, PDF (37/272 Pages) STMicroelectronics – fast 8032 MCU with programmable logic

UPSD33xx
7
8032 MCU registers
8032 MCU registers
The UPSD33xx has the following 8032 MCU core registers, also shown in Figure 10.
Figure 10. 8032 MCU registers
PCH
DPTR(DPH)
A
B
SP
PCL
PSW
R0-R7
DPTR(DPL)
Accumulator
B Register
Stack Pointer
Program Counter
Program Status Word
General Purpose
Register (Bank0-3)
Data Pointer Register
AI06636
) ^7.1
Stack Pointer (SP)
t(s ^{The SP is an 8-bit register which holds the current location of the top of the stack. It is}
c _{incremented before a value is pushed onto the stack, and decremented after a value is}
u _{popped off the stack. The SP is initialized to 07h after reset. This causes the stack to begin}
d _{at location 08h (top of stack). To avoid overlapping conflicts, the user must initialize the top}
ro _{of the stack to 20h if all four banks of registers R0 - R7 are used, and the user must initialize}
P _{the top of stack to 30h if all of the 8032 bit memory locations are used.}
olete 7.2
Data Pointer (DPTR)
bs _{DPTR is a 16-bit register consisting of two 8-bit registers, DPL and DPH. The DPTR register}
O is used as a base register to create an address for indirect jumps, table look-up operations,
- _{and for external data transfers (XDATA). When not used for addressing, the DPTR register}
) _{can be used as a general purpose 16-bit data register.}
t(s _{Very frequently, the DPTR register is used to access XDATA using the External Direct}
c _{addressing mode. The UPSD33xx has a special set of SFR registers (DPTC, DPTM) to}
du ^{control a secondary DPTR register to speed memory-to-memory XDATA transfers. Having}
ro ^{dual DPTR registers allows rapid switching between source and destination addresses (see}
details in Section 11: Dual data pointers on page 56).
lete ^P _7.3
Program Counter (PC)
so _{The PC is a 16-bit register consisting of two 8-bit registers, PCL and PCH. This counter}
b _{indicates the address of the next instruction in program memory to be fetched and executed.}
O _{A reset forces the PC to location 0000h, which is where the reset jump vector is stored.}
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