Serial Interface Chinese dot matrix Character LCD Modules interface mode and timing

OCM4X8C with serial / parallel interface to a variety of ways to facilitate the module with a variety of microcontroller, microprocessor connection.
(1) 4/8 bit parallel interface mode
When the module PSB feet high, the module enters the parallel interface mode. Can function in parallel mode setting command "DL" to select 8-bit or 4-interface mode, the main control system will cater for "RS", "RW", "E" DB0 ~ DB7 to complete the instruction / data transmission, its operation timing and other parallel interface OLED Display is the same.
(2) 2/3 wire serial interface mode
When the pin to low PSB module, the module enters the serial interface mode. Serial mode uses a serial data line and a serial clock line SCLK SID to transmit data, constitute two-wire serial mode.
OCM4X8C also allows simultaneous access to multiple LCD module to complete the multi-information display. At this point, you want to take advantage of chip select "CS" a 3-wire serial interface mode, when the "CS" then high potential, the module can receive and display data properly, otherwise the module displays will be banned. Typically, when the system uses only one liquid crystal display module, "CS" may be connected and fixed to a high level.
Microcontroller and LCD module 1 byte of data transferred between the total of 24 clock pulses. First, the single-chip data transmission to give the start bit, here are five consecutive "1" as the start bit of the data, such as the module receives a continuous 5 "1", the internal transmission is reset and the serial transmission will be synchronized. Then, "RW" bit is used to select the direction of data transfer (read or write), "RS" bit is used to select the internal data registers or the instruction register, and finally the eighth bit is fixed to "0." Upon receiving the start bit and the "RW" and "RW" The first one byte, the next byte of data or instruction will be divided into two bytes to the serial transmission or reception. Data or instructions, the upper four bits are placed in the first two bytes of serial data high 4 bits of the lower 4 bits are set to "0"; data or instruction is placed in the lower 4 bits byte 3 The high 4 bits of the lower 4 bits are also set to "0", so that completion of one byte command or data transmission. It should be noted that, when there are multiple data or instructions to be sent, it must wait until an instruction completes execution is completed before sending the next command or data, otherwise, it will cause an instruction or data loss. This is because the internal TFT Display Module does not send / receive buffer.
The module is constituted by a program with the same type LCD dot matrix LCD module compared, regardless of the hardware circuit structure or display program to be much more simple, and the prices are slightly lower than the same module graphic dot matrix LCD module .