Post by thread:optrex lcd init code

Hi I have several curcuits working with a pic 16c84 driving 1x16 generic lcd displays. The larger displays have been a problem for me. I would appreciate someone stepping me through the init code for the optrex dmc40218. I understand that there is a code of 0x30 sent three times and all of the display on cursor on/off stuff but I am still not getting results. I may have things in the wrong order or may be missing something entirely. My circuit is 8 bit ( not 4 like most of the lit on the net). Thanks for your help! Wil Reeder spam_OUTteachtechTakeThisOuTbc.sympatico.ca Vancouver, Canada

This is my first post to the list! This is what I have done with a 16C56 and an Optrex 20x2 LCD module... 8bit interface. Based on datasheet from Phillips LCD modules Parallax assembler LCDRW equ RA.1 ;Read/Write out 18 LCDRS equ RA.2 ;Register Select out 1 LCDE equ RA.3 ;enable out 2 LCD equ 6 ; PortB bit7..0= pin 13 12 11 10 9 8 7 6 InitLCD ;8 bit interface 20x2 as page 10 ; wait 15ms movlw 72 movwf tmp clrf wtmp :L01 nop decfsz wtmp goto :L01 decfsz tmp goto :L01 bcf LCDRW bcf LCDRS movlw 00111000b movwf PortRB nop bsf LCDE nop nop nop bcf LCDE ;#1 ; wait 4.1ms movlw 20 movwf tmp clrf wtmp :L02 nop decfsz wtmp goto :L02 decfsz tmp goto :L02 movlw 00111000b movwf PortRB nop bsf LCDE nop nop nop bcf LCDE ;#2 ; wait 100us or more =>208us clrf wtmp :L03 nop decfsz wtmp goto :L03 movlw 00111000b movwf PortRB nop bsf LCDE nop nop nop bcf LCDE ;#3 call Wait40us movlw 00111000b movwf PortRB nop bsf LCDE nop nop nop bcf LCDE ;#4 call Wait40us movlw 00001100b movwf PortRB nop bsf LCDE nop nop nop bcf LCDE ;#5 Display On/Off call Wait40us movlw 00000001b movwf PortRB nop bsf LCDE nop nop nop bcf LCDE ;#6 Display Clear movlw 10 movwf tmp clrf wtmp :L04 nop decfsz wtmp goto :L04 decfsz tmp goto :L04 movlw 00000110b movwf PortRB nop bsf LCDE nop nop nop bcf LCDE ;#7 Entry mode set InitEnd Now you just send data to it and wait 40us for it to end the operation, or read the busy flag. Ivan Kocher WIL REEDER wrote: {Quote hidden}> > Hi > > I have several curcuits working with a pic 16c84 driving 1x16 generic lcd > displays. The larger displays have been a problem for me. I would > appreciate someone stepping me through the init code for the optrex > dmc40218. I understand that there is a code of 0x30 sent three times and > all of the display on cursor on/off stuff but I am still not getting > results. I may have things in the wrong order or may be missing something > entirely. My circuit is 8 bit ( not 4 like most of the lit on the net). > Thanks for your help! > > Wil Reeder > .....teachtechKILLspam@spam@bc.sympatico.ca > Vancouver, Canada

> Hi > > I have several curcuits working with a pic 16c84 driving 1x16 generic lcd > displays. The larger displays have been a problem for me. I would > appreciate someone stepping me through the init code for the optrex > dmc40218. I understand that there is a code of 0x30 sent three times and > all of the display on cursor on/off stuff but I am still not getting > results. I may have things in the wrong order or may be missing something > entirely. My circuit is 8 bit ( not 4 like most of the lit on the net). > Thanks for your help! > > Wil Reeder > teachtechKILLspambc.sympatico.ca > Vancouver, Canada > Hello Wil You might want to check out the LCD Technical FAQ. It's at ftp://ftp.armory.com/pub/user/rstevew/LCD/lcdfaq.zip or http://www.paranoia.com/~filipg/HTML/LINK/F_LCD_menu.html Thanks to this FAQ i got a display connected to a 16C57 up and running in very short time. Amongst other things it describes the initialization for both 4-bit and 8-bit mode in detail. ----------------------------------- Ruben Jšnsson AB Liros Elektronik, Sweden .....maxrubenKILLspam.....mail.bip.net -----------------------------------

Wil, make sure you are in the 2-line mode and note the display address for a 40 x 2 display. After the first 3 0x30's send 0x38. The address map is (decimal): Line 1: 0 -> 39 Line 2: 64 -> 103 - Tom At 06:55 PM 1/19/98 -0800, you wrote: {Quote hidden}>Hi > >I have several curcuits working with a pic 16c84 driving 1x16 generic lcd >displays. The larger displays have been a problem for me. I would >appreciate someone stepping me through the init code for the optrex >dmc40218. I understand that there is a code of 0x30 sent three times and >all of the display on cursor on/off stuff but I am still not getting >results. I may have things in the wrong order or may be missing something >entirely. My circuit is 8 bit ( not 4 like most of the lit on the net). >Thanks for your help! > >Wil Reeder >EraseMEteachtechspam_OUTTakeThisOuTbc.sympatico.ca >Vancouver, Canada > >