ml2251 Oki Semiconductor, ml2251 Datasheet - Page 22

• Manufacturer Part Number: ml2251
• Description: 2-channel Mixing Oki Adpcm Algorithm-based Speech Synthesis Lsi
• Manufacturer: Oki Semiconductor

2. Serial Interface
Command and Data Input Timings
OKI Semiconductor
When selecting the serial interface, the I/O pins CS, WR, DW, DI, SCK, RD, and DO are used as input pins to
input various commands and data, and as output pins to read out the status of the commands and data.
The micro-computer interface becomes effective when CS pin is set to “L” level.
To input the commands and data, “L” level is input to CS and WR pins followed by, from MSB, to DI pin in
synchronization with the input clock signal at SCK pin. Data at DI pin is captured inside the device on the rising
or falling edge of the clock at SCK pin. And the command is executed on the rising edge of the WR pin.
The selection of rising/falling edge of SCK clock is determined by the input level of the SCK pin on the falling
edge of the WR pin. If the SCK pin on the falling edge of the WR pin is at “L” level, the DI pin data is captured
inside the device on the rising edge of SCK clock. Conversely, if the SCK pin on the falling edge of the WR pin
is at “H” level, then the DI pin data is captured on the falling edge of SCK clock.
Use the DW pin to input various data after having input the EXT or Flash I/F command. The data input method
is the same as to input data from the WR pin.
• SCK Rising Edge Operation
• SCK falling Edge Operation
WR , DW (I)
WR , DW (I)
SCK(I)
SCK(I)
CS (I)
CS (I)
DI(I)
DI(I)
D7
D7
D6 D5 D4 D3 D2 D1 D0
D6 D5 D4 D3 D2 D1 D0
FEDL2250DIGEST-06
ML2250 family
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