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9.1.6
Set Display Start Low Order Address
Instruction Register
Display Start Address Register (low order byte)
9.1.7
Set Display start High Order Address
Instruction Register
Display Start Address Register (high order byte)
These instructions cause display start addresses to be written in the display start address registers. The display start address
indicates a RAM address at which the data displayed at the top left end on the screen is stored. In the graphic mode, the start
address is composed of high/low order 16 bits. In the character display, it is composed of he lower 4 bits of high order address
(DB3 - DB4) and 8 bits of low order address. The upper 4 bits of high order address are ignored.
9.1.8
Set Cursor Address (low order) (RAM write low order address)
Instruction Register
Cursor Address Counter (low order byte)
9.1.9
Set Cursor Address (high order) (RAM write high address )
Instruction Register
Cursor Address Counter (high order byte)
These instructions cause cursor addresses to be written in the cursor address counters. The cursor address indicates and address
for sending or receiving display data and character codes to or from the RAM.
cursor address are read/written. In the character mode, the cursor is displayed at the digit specified by the cursor address. A
cursor address consists of the low-order address (8 bits) and the high-order address (8 bits). Satisfy the following requirements.
1
When you want to rewrite (set) both the low order address
and the high order address.
2
When you want to rewrite only the low order address.
3
When you want to rewrite only the high order address.
The cursor address counter is a 16 bit up-count with SET and RESET functions. When the bit N Changes from 1 to 0, the bit
N+1 is added by 1. When setting the low order address, the LSB (bit 1) of the high order address is added by 1 if the MSB (bit
*) of the low order address changes from 1 to 0. Therefore, set both the low order address and the high order address as shown
in above table.
9.1.10
Write Display Data
REGISTER
Instruction Register
RAM
After the code $"OC" is written into the instruction register with RS=1, 8 bit data with RS=0 should be written into the data
register. This data is transferred to the RAM specified by the cursor address as display data or character code. The cursor
addre ss is increased by 1 after this operation.
9.1.11
Read Display Data
REGISTER
Instruction Register
RAM
Data can be read from the RAM with RS=0 after writing code $"0D" into the instruction register. The read procedure is as
follows:
This instruction outputs the contents of data output register on Data Bus (DB0 to DB7) and then transfers RAM data specified
by a cursor address to the data output register, also increasing the cursor address by 1. After setting the cursor address,
correct data is not output at the first read but at the second time. Thus, make one dummy read when reading data after setting
the cursor address.
REGISTER
REGISTER
REGISTER
REGISTER
R/W
RS
0
1
0
0
R/W
RS
0
1
0
0
PAGE
PAGE
PAGE
PAGE 7 7 7 7
R/W RS DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
1
0
0
R/W RS DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
1
0
0
R/W RS DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
1
0
0
R/W RS DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0
1
0
0
Set the low order address and then set the high order
address.
Don't fail to set the high order address again after setting
the low order address.
Set the high order address.
order address again.
DB7
DB6
DB5
0
0
0
MSB (pattern data, character code) LSB
DB7
DB6
DB5
0
0
0
MSB (pattern data, character code) LSB
0
0
0
0
(Start low order address) Binary
0
0
0
0
(Start high order address) Binary
0
0
0
0
(Cursor low order address) Binary
0
0
0
0
(Vp -1) Binary
Namely, data at address specified by the
You don't have to set the low
DB4
DB3
DB2
0
1
1
DB4
DB3
DB2
0
1
1
1
0
0
0
1
0
0
1
1
0
1
0
1
0
1
1
0
(Hp -1) Binary
DB1
DB0
0
0
DB1
DB0
0
1
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