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ABOV Semiconductor Co., Ltd.
SINTCR (System Interrupt Control Register) : F7H
Initial value : 00H
Stack Pointer Overflow Interrupt
When SPOVF Interrupt occurs, this bit becomes ‘1’. The flag
is cleared only by writing a ‘0’ to the bit. So, the flag should
be cleared by software.
Stack pointer overflow Interrupt no generation
Stack pointer overflow Interrupt generation
NOTE)
1. When the XSPEN bit of the XSPCR register is “0b”
- The stack pointer (SP) register is compared to the stack pointer watch low register (SWARL).
- If the values are same (SP[7:0] == SWARL[7:0]), the SPOVIFR bit is set to “1b”.
- At this time, the XSP and SWARH registers are don’t care.
2. When the XSPEN bit of the XSPCR register is “1b”
- The extended stack pointer and stack pointer (XSP:SP) registers are compared to the stack
pointer watch high and low register (SWARH:SWARL).
- If the values are same (XSP:SP[15:0] == SWARH:SWARL[15:0]), the SPOVIFR bit is set to “1b”.
XBANK (XRAM Bank Pointer) : F8H
Initial value : 00H
NOTE)
1. This XBANK register holds the [15:8] part of memory address during access to data.
2. Address[15:0]: “XBANK:Ri” (Ri: R0 or R1)
3. Ex) MOVX A,@Ri ; Move external data (XBANK:Ri[15:0]) to A
MOVX @Ri,A ; Move A to external data (XBANK:Ri[15:0])