A microprocessor-based dot matrix display system for Japanese Hiragana syllables

摘要

A microprocessor-based 5*7 dot-matrix display system for Japanese Hiragana syllables is proposed. The dot-matrix layout for each of the 68 syllables is shown. The syllable generation or the selective dots to produce a display is accomplished using a column approach, i.e. 7 dots (comprising one column) are displaced at a time with proper multiplexing, the display of each syllable is completed in 5 steps. A complete Hiragana word typically comprises one to four syllables. A four-syllable string (i.e., four 5*7 dot-matrix displays) display system is therefore proposed. The organization of the microprocessor-based hardware for such a display system is discussed and the system flowchart is given. Each character in the string is presented as a 7-bit ASCII code to the microprocessor. A program compares the character string that is input and selects the appropriate Hiragana syllables for display from a look-up table of bit patterns stored in memory. As each Hiragana syllable requires (5*7)+35 dots (or bits), five bytes of data are used to represent one syllable, ignoring the last bit of each byte. To represent the full 68 Hiragana syllables, a total of 340 bytes of memory locations are required.