KDC-MP6090R/MP7018/MP8017
15
CIRCUIT DESCRIPTION (MP3)
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READ OPERATION (see Fig. 8)
• Curent byte address read
The RTA013 has an internal byte adress counter. Each
time a byte is written or read, this counter is incremented.
For the current byte address read mode, following a
START condition the master sends the device address
with the RW bit set to 1.
The STA013 acknowledges this and outputs the byte
address by the internal byte address counter. The master
does not acknowledge the received byte, but terminates
the transfer with a STOP condtion.
• Sequential address read
This mode can be intiated with either a curret address read
or a rendom address read. However in this case the mas-
ter does acknowledge the data byte output and the
STA013 countinuse to output the next byte in sequence.
To terminate the streams of byte the master does not
anknowledge the last receivesd byte, but terminates the
transfer with a STOP condition.
The output data stream is from consective byte address,
with the interminal byte address counter automatically
incremented after one byte output.
DEV-ADDR
DEV-ADDR
SUB-ADDR
DATA
RW
START
START
START
STOP
ACK
RW
RW
STOP
STOP
RW=HIGH
ACK
ACK
ACK
ACK
ACK
ACK
NO ACK
NO ACK
DEV-ADDR
DATA
DATA
NO ACK
DEV-ADDR
START
DEV-ADDR
DEV-ADDR
SUB-ADDR
START
START
RW
ACK
RW
STOP
ACK
ACK
ACK
NO ACK
ACK
DATA
DATA
DATA
DATA
DATA
CURRENT
ADDRESS
READ
RANDOM
ADDRESS
READ
SEQUENTIAL
CURRENT
READ
SEQUENTIAL
RANDOM
READ
Fig. 8 Read Mode Sequence
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MP3 Playing Procedure
1. A request for read (minute, second, frame) occurs in the
MP3 decoder control within the mechanical micon (IC1).
2. The mechanical control within the mechanical micon sets the
requested time on the ROM decoder and conducts search.
3. The data is accumulated in the DRAM (IC6) attached to
the ROM decoder (IC2.)
4. Loading is completed as
there is no ECC error.
5. The time when the error occurred
is set on the requested time.
6. Copying is conducted by one-sector (2048Kbyte) DMA from
DRAM (IC6) to internal RAM of the mechanical micon (IC1)
7. Copy complete is sent to the MP3 decoder control within
the mechanical micon.
8. MP3 decoder within the mechanical micon (IC1) begins serial transfer
by DMA to the MP3 decoder (IC5). The sequence goes back to “1”.
No error
Error
