8XC251SA, SB, SP, SQ USER’S MANUAL
C-26
SPH
Address: S:BEH
Reset State: 0000 0000B
Stack Pointer High. SPH provides SFR access to location 62 in the register file (also named SPH).
SPH is the upper byte of the lower word of DR60, the extended stack pointer (SPX). The extended
stack pointer points to the current top of stack. When a byte is saved (PUSHed) on the stack, SPX is
incremented, and then the byte is written to the top of stack. When a byte is retrieved (POPped) from
the stack, it is copied from the top of stack, and then SPX is decremented.
7 0
SPH Contents
Bit
Number
Bit
Mnemonic
Function
7:0 SPH.7:0 Stack Pointer High:
Bits 8–15 of the extended stack pointer, SPX (DR60).
To Next Page
Loading...
