Abstract: Through a small man-machine contact surface unit design practice, in detail introduced one kind based on AT89S52 the monolithic integrated circuit Chinese fonts liquid crystal HG240128R hardware and the software use usage. Has produced its hardware connection chart and the partial software procedure code.

Clear reaches the HG240128R series liquid crystal display module which the photoelectricity technology limited company develops, compares with the similar product, has the demonstration information content in a big way, the programming simple, the volume small, the quality is light and so on many merits, is suitable to the motion communication, the instrument measuring appliance, the electronic installation and so on each kind of domain.

Under take HG240128R in certain man-machine contact surface unit practical application system as the example, in detail elaborates the HG240128R liquid crystal display module application.

1. HG240128R module explanation
The HG240128R liquid crystal display module for 240×128 the lattice, the control chip uses RA8820, can hold 16×16 the lattice Chinese character altogether 15/ line of ×8/ rows, in constructs 512KByte 16*16 Chinese demonstration glyph ROM, stores up 7,602 standards GB code simplified Chinese. This component external dimensions for 140×82mm, demonstrated the size for 114×64mm, demonstrated the pattern may choose STN yellow green /STN blue /STN ash /FSTN.
A table connection definition
Foot position mark effective level function
1 Vss - power source place
2 Vdd - logic voltage
3 Vo - liquid crystal actuation negative voltage
4 C/D  / L instruction data access channel H: Instruction, L: Data
5 /RD L reads the signal
6 /WR L writes the signal
7~14 DB0 H/L data bus
15 /CS L 片� signal
16 /RESET L replacement signal
17 Vee - negative pressure output
18 BUSY H/L busy flag bit
19 INT - look-at-me
20 A - back light voltage +

2. systems hardware composition
3. software designs
This system software design uses the MCS51 series assembly instruction establishment to become.
Under explains this liquid crystal through the demonstration graph and the Chinese character procedure the usage.
Software flow chart as follows:
Partial subroutines code as follows:
4. concluding remark
Through this article introduced has understood the Chinese fonts liquid crystal HG240128R usage