MAS3587F Micronas, MAS3587F Datasheet - Page 70

• Manufacturer Part Number: MAS3587F
• Description: MPEG Layer 3 Audio Encoder/Decoder
• Manufacturer: Micronas

MAS 3587F
4.6.3.6. PIO as Parallel Input Interface: DMA Mode
In decoding mode, the data transfer can be started
after the EOD pin of the MAS 3587F is set to “high”.
After verifying this, the controller signalizes the send-
ing of data by activating the PR line. The MAS 3587F
responds by setting the RTR line to the “low” level. The
MAS 3587F reads the data PI[19:12] and sets RTR to
low after rising edge of PR. After RTR is set to high,
the mC sets PR to low. The next data word write oper-
ation will be initialized again by setting the PR line via
the controller. Please refer to Figure 4–26 for the exact
timing
The procedure above will be repeated until the
MAS 3587F sets the EOD signal to “0” which indicates
that the transfer of one data block has been executed.
Subsequently, the controller should set PR to “0”, wait
until EOD rises again and then repeat the procedure to
send the next block of data. The DMA buffer is
15 bytes long.
The buffer size is subject to change in the next version.
.
EOD
PR
RTR
PI[19:12]
Fig. 4–26: Handshake protocol for writing MPEG data to the PIO-DMA
70
t
st
t
set
t
Byte 1
r
t
pd
t
rtrq
t
pr
t
h
MAS 3509F latches the PIO DATA
t
rpr
Symbol
t
t
t
t
t
t
t
t
t
t
st
r
pd
set
h
rtrq
pr
rpr
eod
eodq
Byte 15
Pin
Name
PR, EOD
PR, RTR
PR,
PI[19:12]
PI[19:12]
PI[19:12]
RTR
PR
PR, RTR
PR, EOD
EOD
t
eod
t
Min.
0.010
40
120
160
160
200
480
160
40
2.5
eodq
ADVANCE INFORMATION
Max.
2000
160
480
30000
160
500
high
low
high
low
high
low
high
low
Micronas
Unit
ns
ns
ns
ns
ns
ns
ns
ns
s
s