Specifications

S1C62N82 TECHNICAL HARDWARE EPSON I-79
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Melody Generator)
(d)Address counter
The configuration of the melody ROM address counters is
shown in Figure 4.11.5. It consists of a counter in which
note playing end signal generated from the note generator
is entered and which increases the melody ROM ad-
dresses by 1 address every time a note playing is com-
pleted. Moreover, when a melody playing begins, address
register data (MAD0 to MAD6) are set on these counters.
This causes the address set in the address register to
specify the melody ROM address.
MAD0
Melody ROM Address
MAD1 MAD2 MAD3 MAD4 MAD5 MAD6
Note playing
end signal
Fig. 4.11.5
Address counters
(e)Melody ROM
The melody ROM is a mask ROM with 128 words × 10
bits capacity in which data of the melody to be played
(note, interval, end-of-melody, etc.) is stored beforehand.
Any number of melodies may be stored as long as the
total number of notes is within 128 words (basically, 1
note/word). Details regarding the melody ROM configu-
ration, etc., can be found in next Section, "Melody data".