ml7084-001 Oki Semiconductor, ml7084-001 Datasheet - Page 209

• Manufacturer Part Number: ml7084-001
• Description: 4ch Voip Codec
• Manufacturer: Oki Semiconductor

Perform melody regeneration control with this melody generator only after making a transition to the high-speed
read mode shown below.
• High-Speed Melody Read Mode
OKI Semiconductor
The mode transitions to the high-speed melody read mode (MGEN_FRFLAG = 1) when the melody generator
high-speed read mode control register (MGEN_FREN) is set to “1”.
In this high-speed melody read mode, melody data regenerated by the melody generator is encoded in the
selected coding format, and a read request is issued to the MCU side. Because this read request is issued at a
higher speed compared to a read request of speech data, melody data can be transferred to RAM or other storage
on the MCU side in short time. Figure 60 shows a control flow of the high-speed melody read mode, and Figure
61 shows its control timing.
Reading from outside
Automatic processing
inside the LSI
Conditional branch
External setting
Figure 60 Control Flow in High-Speed Melody Read Mode
High-speed melody read mode
Stop the high -speed melody read mode and speech codec
No
Activate the high -speed melody read mode
Set the melody generator output control
Read melody data from transmit buffe r
Is reading of the last data complete
Activate the speech codec
(MGEN_FREN=SC _CH0EN="0")
Specify the coding format for the
Set tune data [time/frequency ],
transmit side speech codec .
Is read request issued ?
MGEN_FRFLAG="0"
Set the buffering time .
MGEN_FRFLAG="1"
(MGEN_FREN="1")
(SC_CH0EN="1")
gain, fade control
(FR0B ="0")
CR4
Yes
Yes
Approx . 250 μs
(CH0)
?
No
Melody generator and
Melody regeneration
High-speed read mode
reading in progress
Initial settings
and high -speed
speech codec
Activation 2
Activation 1
Stop
FEDL7224-001FULL-01
ML7224-001TC
209/225