Changes

Some features of the Z80

18 bytes added, 20:29, 29 December 2018
/* Flags/Status Register (F and F') */
Note:
There are two bits in the flags register which are documented by Zilog as being unused. But in fact these bits do change: these bits are updated according to an undocumented register of the Z80 named either WZ or MEMPTR. This undocumented register is used to store temporary results such as 16-bits arithmetic results, and address (for example, loading I register and the vector byte for interruption mode 2 to compute the value to load in PCregister).
== Sign flag ==
20
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