RW1068 ETC-unknow, RW1068 Datasheet - Page 16

• Manufacturer Part Number: RW1068
• Description: 26com/84seg Driver & Controller For Dot Matrix Lcd
• Manufacturer: ETC-unknow

This chip has all three kinds interface type with MPU : serial, 4-bit bus and 8-bit bus. Serial and bus
(4-bit/8-bit) is selected by PSB input, and 4-bit bus and 8-bit bus is selected by IF bit in the instruction
register. During read or write operation, two 8-bit registers are used. One is data register (DR), the
other is instruction register (IR). The data register (DR) is used as temporary data storage place for
being written into or read from DDRAM/CGRAM/SEGRAM, target RAM is selected by RAM address
setting instruction. Each internal operation, reading from or writing into RAM, is done automatically.
So to speak, after MPU reads DR data, the data in the next DDRAM/CGRAM/SEGRAM address is
transferred into DR automatically. Also after MPU writes data to DR, the data in DR is transferred into
DDRAM/CGRAM/SEGRAM automatically.
The Instruction register (IR) is used only to store instruction code transferred from MPU. MPU cannot
use it to read instruction data. To select register, use RS input pin in 4-bit/8-bit bus mode (PSB =
"High") or RS bit in serial mode (PSB= "Low").
When BF = "High", it indicates that the internal operation is being processed. So during this time the
next instruction cannot be accepted. BF can be read, when RS = Low and R / W = High (Read
Instruction Operation), through DB7 Before executing the next instruction, be sure that BF is not High.
RS
0
0
1
1
FUNCTION DESCRIPTION
SYSTEM INTERFACE
BUSY FLAG (BF)
R/W
0
1
0
1
Instruction write operation (MPU writes Instruction code into IR)
Read busy flag (DB7) and address counter (DB0 - DB6)
Data write operation (MPU writes data into DR)
Data read operation (MPU reads data from DR)
26COM/84SEG DRIVER & CONTROLLER FOR DOT MATRIX LCD
RockWorks Technology Corp.
16
Operation
RW1068