7 programming notes – Epson S1C88650 User Manual

Page 46

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38

EPSON

S1C88650 TECHNICAL MANUAL

5 PERIPHERAL CIRCUITS AND THEIR OPERATION (System Controller and Bus Control)

5.2.7 Programming notes

(1)

______

All the interrupts including NMI are masked,
until you write the optional value into both the
"00FF00H" and "00FF01H" addresses. Conse-
quently, even if you do not change the content
of this address (You use the initial value, as is.),
you should still be sure to perform the writing
operation using the initialization routine.

(2) When setting stack fields, including page

addresses as well, you should write them in the
order of the register SPP ("00FF01H") and the
stack pointer SP.

Example: When setting the "178000H" address

LD

EP, #00H

LD

HL, #0FF01H

LD

[HL], #17H

LD

SP, #8000H

During this period the
interrupts (including

_______

NMI) are masked.

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