HD66727 Datasheet, PDF (37/97 Pages) Hitachi Semiconductor – Low-Power Dot-Matrix Liquid Crystal Display Controller/Driver with Key Scan Function

HD66727
Annunciator/SEGRAM Address Set
The annunciator/SEGRAM address set instruction (Figure 18) includes the DA and A (AAN/ASEG) bits.
DA: Turns annunciator display on or off. When DA = 1, annunciator display is turned on and driven
statically. When DA = 0, annunciator display is turned off with ASEG1 to ASEG10 and ACOM pins held
to V_CC level.
The internal operating clock supply is halted during the standby mode; make sure to turn off display (DA =
0) if the external alternating signal is not supplied. For details, refer to the Segment Display and
Annunciator Display section and the Standby Mode section.
AAAA: Used for setting the SEGRAM address into the address counter (AC) or for directly setting the
annunciator address. The SEGRAM addresses range from 1000H to 1111H (8 addresses), while the
annunciator addresses range from 0000H to 0010H (3 addresses).
The annunciator address is directly set without using the address counter, and consequently must be
updated for each access. The annunciator address can be set even during the sleep and standby modes.
Once the SEGRAM address is set, data in the SEGRAM can be accessed consecutively since the address
counter is automatically incremented or decremented by one according to the I/D bit setting after each
access. The SEGRAM address cannot be set during the sleep or standby mode.
AAAA is the address for setting the 0011 LED/general port data; 0100 is the address for setting the
SEG/COM shift direction. See 'Annunciator Driver Circuit' for details.
RS R/W DB7
DB0
0 0 1 0 0 DA A A A A
Figure 18 Annunciator/SEGRAM Address Set Instruction
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