Why pay for Serial LCDs when you can make your own?
HD44780 based LCD displays are very popular for embedded projects because they are cheap, easy to interface, can display characters, consume power lot less than seven-segment displays, and most of the present day compilers have in-built library routines for them. However, the only disadvantage is that they require at least 6 I/O pins of microcontroller. Well, you may ask, isn’t that less than what seven-segment displays require? Yes, that’s true but there are circumstances where you don’t have left enough pins for LCD display. For example, if you are going to design a temperature sensor based on a PIC12F683 microcontroller, which has just 6 I/O pins, you won’t have pins for interfacing a LCD. One solution for cases like that is to use serial LCD’s. Serial LCD’s available in the market cost more than double of HD44780 based standard one. The serial LCD’s still have the standard LCD module but it has an extra built-in driver module that receives data/command from a host microcontroller in serial format and convert it to appropriate parallel format suitable for HD44780 driver input.
