Changes
Z80
,/* Internal state */
The NMI vector is fixed at 0066h, regardless of the I register, and of the IM interrupt mode.
|-
| IFF1 || 1-bit || Main Instruction Fetch Interrupt Flip-Flop || Set when interrupts are enabled, cleared on disable.
When the CPU accepts a maskable interrupt, both IFF1 and IFF2 are automatically cleared, inhibiting further interrupts.
|-
