GMS81508A Datasheet, PDF (16/91 Pages) Hynix Semiconductor – USERS MANUAL

GMS81508/16
 Break Flag ( B )
This flag is set by BRK (S/W interrupt) instruction to distinguish BRK and TCALL instruction having
the same vector address.
 Direct Page Flag ( G )
This flag assign direct page (0-page, 1-page) for direct addressing mode. When G-flag is "0", the
direct addressing space is in 0-page(0000H~00FFH). When G-flag is "1", the direct addressing
space is in 1-page(0100H~01FFH).
It is set and cleared by SETG, CLRG instruction
 Overflow Flag ( V )
This flag functions when one word is added or subtracted in binary with the sign. When results
exceeds +127 or -128, this flag is set.
When BIT instruction is executed, The bit6 of memory is input into V-flag.
This flag is cleared by CLRV instruction, but set instruction is not exist.
It is a branch condition flag of BVS, BVC.
 Negative Flag ( N )
N-flag is set when the result of a data transfer or operation is negative (bit7 is “1”).
it means the bit-7 of memory is sign bit. thereby data is valid in the range of -128 ~ +127.
When BIT instruction is executed, The bit7 of memory is input into N-flag.
Set or clear instruction is not exist.
It is a branch condition flag of BPL, BMI instruction.
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