Lcd Unit Usage Instructions; Interface With External Microprocessor - Sharp LM161 Series User Manual

LCD UNIT USAGE INSTRUCTIONS

Interface with External Microprocessor

1. 8-bit Microprocessor
RS
R/W
E
OPERATING
STATUS
DB DATA
7
Write Instruction
a. Interface to 8-Bit Microprocessor via Peripheral
Interface Adaptor (PIA). The following exempli-
fies the connection of the LCD unit to an 8-bit
microprocessor chip through a PIA or I/0 port.
The interface is TTL compatible. PB
the interface device are connected to DB
of the LCD unit, and PA
E, R/W, and RS respectively.
When the PIA is used, care must be taken to
insure the proper relationship between the E
signal and other signals when reading and writ-
ing data.
MC6800
DB
Display Unit User's Manual
INTERNAL OPERATION
BUSY
Check Busy Flag
Figure 8. 8-Bit Interface Timing (Example)
- PB
0 7
- DB
0
- PA are connected to
0 2
A CS
15
A CS
14
A CS
13
A RS
1
A RS
0
R/W R/W
VMA
E
φ
2
8
- DB D
0 7
BUSY
Check Busy Flag Check Busy Flag
of
7
2
PA
1 2
0
PA
1 1
0
MC6821
PA
0
8
PB - PB
0 7
- D
0 7
Dot-Matrix LCD Units
READY FOR DATA
NOT
DATA
BUSY
Write Instruction
RS
R/W
LCD UNIT
E
DB - DB
0 7
LCD27-27
LCD27-28
21