FEDL9205-03
1
Semiconductor
ML9205-01
Data Transfer Method and Command Write Method
Display control command and data are written by an 8-bit serial transfer.
Write timing is shown in the figure below.
Setting the CS pin to "Low" level enables a data transfer.
Data is 8 bits and is sequentially input into the DA pin from LSB (LSB first).
As shown in the figure below, data is read by the shift register at the rising edge of the shift clock, which is input
into the CP pin. If 8-bit data is input, internal load signals are automatically generated and data is written to each
register and RAM.
Therefore it is not necessary to input load signals from the outside.
Setting the CS pin to "High" disables data transfer. Data input from the point when the CS pin changes from
"High" to "Low" is recognized in 8-bit units.
tDOFF
tCSH
CS
CP
B0 B1 B2 B3 B4 B5 B6 B7
LSB MSB
B0 B1 B2 B3 B4 B5 B6 B7
LSB MSB
B0 B1 B2 B3 B4 B5 B6 B7
LSB MSB
DA
1st byte
2nd byte
2nd byte
Character code data of the
next address
When data is written
to DCRAM*
Command and address data
Character code data
*
When data is written to RAM (DCRAM, ADRAM, CGRAM) continuously, addresses are internally
incremented automatically.
Therefore it is not necessary to specify the 1st byte to write RAM data for the 2nd and later bytes.
Reset Function
Reset is executed when the RESET pin is set to "L", (when turning power on, for example) and initializes all
functions.
Initial status is as follows:
• Address of each RAM ....................................... address "00"H
• Data of each RAM............................................. All contents are undefined
• General output port............................................ All general output ports go "Low"
• Display digit ...................................................... 24 digits
• Brightness adjustment........................................ 8/16
• All display lights ON or OFF ............................ OFF mode
• Segment output.................................................. All segment outputs go "Low"
• AD output .......................................................... All AD outputs go "Low"
Please set the functions again according to "Setting Flowchart" after reset.
15/34
OKI [ OKI ELECTRONIC COMPONETS ]
