Demo Music Rom Access - Casio SK-5 Service Manual & Parts Manual

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11. DEMO. MUSIC ROM ACCESS
Demo Music ROM
CE1 01 02 СР 21-04
"Data bus D4-D7 )
I CPU 100 A
MsMe282-05Gs 107
Data bus DOY D7 -
pPD43256C-12L
Assigning Demo Music ROM by being LOW of signal CE2, CPU reads data from the ROM directly
and generates programmed melody and accompaniment signals.
Since the data bus D4 ~ D7 carries data and address, signal OP determines either the bus carries
data or address.
Signal C1 and C2 are clock pulse for data transfer.
OP D4 ~ 07
HIGH Data
LOW Address
2.545
7 ИШ ШИШЕ 0411. ˆ ЙД
ο ПИШИ ‫ااا‬‎ uuuuuyg UUUU
кенеттен н EM
μυ...
DBA ‫د‬ ‫س‬ ‎
DE σσ mem i
Time Chart of Data Transfer
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