Hello Tan. I suggest you a solution with one pin of a PIC. I haven't proved it if it works, but it's an idea at least. Use some sort of 4094, outputs to LCD d7..d4, d/i, r/w and E. E must be t= ied to Vss by a resistor. Connect an output pin of a PIC to D input, by C to clock with resistor ti= ed to Vdd and by diode to STR. STR input has a capactor to Vss and resistor to Vdd. OE of 4094 is in hig= h state all the time. Output of a PIC is at high level, so STR, CLK is high as well, the output= is enable. When you drive output to low level for a certain time, STR and CLK signal= s go to low. the output of 4094 is NC. STR is going to Vdd and when reached high level with input still in low level, zero will be written to serial register. If input low level isn't long enough to allow CLK reachs high, the one wi= ll be written to serial register in the time when input gets from low to hig= h level. When input stay enough long in high level, the STR input gets high and writes result to output buffer. Hope it helps you a little. Igor -----Original Message----- From: pic microcontroller discussion list [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of WH Tan Sent: 15. =FAnora 2003 19:31 To: PICLIST@MITVMA.MIT.EDU Subject: Re: [PIC]: [EE]: 1 I/O interface to LCD - ONE chip solution Actually my main goal is to interface with only one PIC's I/O. Then I work out my 1st design, which used 5 chips(8-bits mode)/4 chips(4-bits mode). And Bob suggested to me a 2 chips solution. Thanks for your reply. Regards. WH Tan ----- Original Message ----- From: "Marcelo Puhl" To: Sent: Saturday, February 15, 2003 10:27 PM Subject: Re: [PIC]: [EE]: 1 I/O interface to LCD - ONE chip solution > What about this one chip solution: > > http://www.myke.com/lcd.htm > -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu