HD66727 Datasheet, PDF (41/97 Pages) Hitachi Semiconductor – Low-Power Dot-Matrix Liquid Crystal Display Controller/Driver with Key Scan Function

HD66727
Write Data to RAM
The write data to RAM instruction (Figure 21) writes 8-bit data to annunciator or DDRAM, lower 6-bit
data to LED port, SEGRAM or CGRAM, or lower two bits to shift direction change bits of SEG/COM that
is selected by the previous specification of the address set instruction (annunciator/LED/SEGRAM address
set, CGRAM address set, or DDRAM address set).
After a write, the address is automatically incremented or decremented by 1 according to the I/D bit setting
in the entry mode set instruction. The annunciator or LED port address is not automatically updated; it must
be specifically updated to write data to a different address. During the sleep and standby modes, DDRAM,
CGRAM, or SEGRAM cannot be accessed.
RS R/W DB7
DB0
1 0 DDDDDDDD
Figure 21 Write Data to RAM Instruction
Read Data from RAM
The read data from RAM instruction (Figure 22), reads 8-bit data from DDRAM, or 5-bit data from
CGRAM or SEGRAM that is selected by the previous specification of the address set instruction
(SEGRAM address set, CGRAM address set, or DDRAM address set). The unused upper three bits of
CGRAM or SEGRAM data are read as 000; annunciator data cannot be read. If no address is specified by
the address set instruction just before this instruction, the first data read will be invalid. When executing
consecutive read instructions, the next data is normally read from the next address.
After a read, the address is automatically incremented or decremented by 1 according to the I/D bit setting
in the entry mode set instruction.
RS R/W DB7
DB0
1 1 DDDDDDDD
Figure 22 Read Data from RAM Instruction
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