Toshiba TMP87CP24AF - Manual (Page 15)

TOSHIBA
TMP87CM24A/P24A
MSB LSB
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Stack Pointer (SP)
1.7.2 Stack Pointer (SP)
The stack pointer (SP) is a 16-bit register containing the address
of the next free locations on the stack.
The SP is post-decremented when a subroutine call or a push
instruction is executed, or when an interrupt is accepted; and
the SP is pre-incremented when a return or a pop instruction is
executed. Figure 1-8 shows the stacking order.
The SP is not initialized hardware-wise but requires initialization by an initialize routine (sets the highest
stack address). [LD SP, mn], [LD SP, gg] and [LD gg, SP] are the SP access instructions (mn; 16-bit
immediate data, gg; register pair).
Figure 1-7. Stack Pointer
Example 1 :To initialize the SP
LD SP, 083FH
Example 2 : To read the SP
LD HL, SP
; SP<-083F h
; HL<-SP
Figure 1-8. Stack
1.8 System Clock Controller
The system clock controller consists of a clock generator, a timing generator, and a stand-by controller.
Figure 1-9. System Clock Controller
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