Post by thread:[EE]: LCD Pinout needed please

Hello, If it is a 14 pin connector you can safely assume that they are all the same. This 14 pin connector is quite standardized. Normally it looks something like this (no guarantees) Pin Signal 1 VCC 2 GND 3 VLCD/VO 4 RS 5 RE 6 E 7 D0 8 D1 9 D2 10 D3 11 D4 12 D5 13 D6 14 D7 Other wise try to track the signal from the HD44780(with the data sheet beside it) to the Connector. grtz Simon --- arpit <spam_OUTarpitTakeThisOuTOPTUSHOME.COM.AU> wrote: > Hello everyone. {Quote hidden}> Some time ago I purchased an lcd display which I > cannot find the pinnout for. The model is not listed > on the oprex site. I have put the details as well as > pictures on > > http://members.optushome.com.au/arpit/ > > Please help me find a pinnout. Thanks in advance, > Arpit. > > -- > http://www.piclist.com hint: PICList Posts must > start with ONE topic: > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other > [BUY]:,[AD]: ->Ads > > > __________________________________________________ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

On Sat, 12 Jan 2002 12:18:03 +0000, Simon-Thijs de Feber wrote: >Hello, > >If it is a 14 pin connector you can safely assume that >they are all the same. >This 14 pin connector is quite standardized. > >Normally it looks something like this (no guarantees) >Pin Signal >1 VCC >2 GND You've got these two pins are swapped. Vcc (Vss) is on pin 2 and ground (Vee) is on pin 1. (See below for a possible cause of this swap.) {Quote hidden}>3 VLCD/VO >4 RS >5 RE >6 E >7 D0 >8 D1 >9 D2 >10 D3 >11 D4 >12 D5 >13 D6 >14 D7 > >Other wise try to track the signal from the >HD44780(with the data sheet beside it) to the >Connector. For me, one irritating thing about LCDs is that the header is commonly (always?) attached from the back side of the PCB. Mechanically, that makes good sense to do but it sure complicates the pin numbering. The outside conductor of the ribbon cable (normally referred to as 'pin 1') ends up going to pin 2 of the LCD. All of the odd pins are mirrored to the even pins and vice versa because of this rear mounting of the header. Does anyone know of a convenient way to keep from screwing up these connections? I manage to get them wrong way too often. Regards, Bob -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

Thankyou all . I know have it up and working. *********** REPLY SEPARATOR *********** On 1/12/2002 at 6:56 AM Bob Barr wrote: {Quote hidden}>On Sat, 12 Jan 2002 12:18:03 +0000, Simon-Thijs de Feber wrote: > >>Hello, >> >>If it is a 14 pin connector you can safely assume that >>they are all the same. >>This 14 pin connector is quite standardized. >> >>Normally it looks something like this (no guarantees) >>Pin Signal >>1 VCC >>2 GND > >You've got these two pins are swapped. Vcc (Vss) is on pin 2 and >ground (Vee) is on pin 1. (See below for a possible cause of this >swap.) > >>3 VLCD/VO >>4 RS >>5 RE >>6 E >>7 D0 >>8 D1 >>9 D2 >>10 D3 >>11 D4 >>12 D5 >>13 D6 >>14 D7 >> >>Other wise try to track the signal from the >>HD44780(with the data sheet beside it) to the >>Connector. > >For me, one irritating thing about LCDs is that the header is commonly >(always?) attached from the back side of the PCB. Mechanically, that >makes good sense to do but it sure complicates the pin numbering. > >The outside conductor of the ribbon cable (normally referred to as >'pin 1') ends up going to pin 2 of the LCD. All of the odd pins are >mirrored to the even pins and vice versa because of this rear mounting >of the header. > >Does anyone know of a convenient way to keep from screwing up these >connections? I manage to get them wrong way too often. > > >Regards, Bob > >-- >http://www.piclist.com hint: PICList Posts must start with ONE topic: >[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

Jinx wrote: > > I can't read the chip numbers ;-(( One will be the interface > IC (HD44780 or similar) the other will be the supplemental > driver > > You can usually easily find the IC pin that a terminal goes > to with an ohm meter. If you have a data sheet for the IC, > bingo. Don't count on the header being the same as another > model - been caught like that. The chances are that it will > be, but assume nothing. Absolutely essential you identify > the 0V and supply pins, LCDs hate it backwards And always power up unknown devices with a 1k or 560 ohm resistor on the +5v rail. In most cases it will allow enough current to run the device, but should prevent any damage if you connect it wrong. :o) -Roman -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

part 1 942 bytes content-type:text/plain; charset=us-ascii (decoded quoted-printable) Roman Black wrote... >And always power up unknown devices with >a 1k or 560 ohm resistor on the +5v rail. >In most cases it will allow enough current >to run the device, but should prevent any >damage if you connect it wrong. :o) Good advice. But sometimes you need current limiting for safety AND an accurate output voltage, at the same time. The attached diagram shows a "safe" power supply circuit I use for such situations: it provides a stable 5.1V output with a hard current limit of 15 milliamps. D2 determines the output voltage; if a more accurate 5V output is needed, substitute an LM236-5.0 for the Zener diode. R2 sets the current limit, according to Iout(max) = ( 0.6V / R2 ) + 1.0 mA where the extra 1.0 mA at the end comes from base feed resistor R1. Simple, accurate, handy, and practically incapable of destroying ANYTHING. Dave Dilatush part 2 7564 bytes content-type:image/gif; name=SafePWR.gif (decode) part 3 144 bytes -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics

>For me, one irritating thing about LCDs is that the header is commonly >(always?) attached from the back side of the PCB. Mechanically, that >makes good sense to do but it sure complicates the pin numbering. >The outside conductor of the ribbon cable (normally referred to as >'pin 1') ends up going to pin 2 of the LCD. All of the odd pins are >mirrored to the even pins and vice versa because of this rear mounting >of the header. >Does anyone know of a convenient way to keep from screwing up these >connections? I manage to get them wrong way too often. >Regards, Bob ********** Perhaps this section from one of my previous posts may help {Quote hidden}> > > >A) > >1 2 > >3 4 > >5 6 > >7 8 > >9 10 > >11 12 > >13 14 > > Standard dual row headers use the pin order in (A) above. > While it is true that the standard pin identification for a dual row header is as shown above, it is NOT the proper order when the pins exit from the BACK of the board, as they do on every LCD module that *I* have ever run across. Because the LCD header is always coming out the BACK of the LCD board, you can easily get confused when using a standard ICD cable to connect the LCD to a standard ICD header. The pin numbering gets exchanged, and if you are not aware of this, then you can easily mess up the wiring on your PIC board. The problem occurs because one of the headers (LCD) is actually mirror-imaged since it comes out the BACK of the LCD board. If the PIC board ALSO had it's header coming off the BOTTOM of it's board, then all would be OK. But the PIC board normally has the header on the TOP of the board. Viewed from the BACK side of the LCD board, which is the side where the pins stick out, it's like this: 13 14 11 12 9 10 7 8 5 6 3 4 1 2 * or, if rotated it can look like 1 3 5 7 9 11 13 2 4 6 8 10 12 14 * or * 2 1 4 3 6 5 8 7 10 9 12 11 14 13 or * 2 4 6 8 10 12 14 1 3 5 7 9 11 13 You will notice the (*) I placed next to pin (2) in each of these diagrams. THAT is the pin that pin (1) of the IDC CABLE connects to. This is a very important fact to take note of, because most likely that IDC cable will then connect to an IDC header on the board with the PIC, and THAT will have its pins sticking up from the TOP of the PIC board. The net result is that the pins end up getting switched around as follows, when using a standard IDC cable: LCD Header IDC CABLE PIC IDC header LCD FUNCTION 1 2 2 Vss (Gnd) 2 1 1 Vdd (+5) 3 4 4 Vo cobtrast adj. 4 3 3 RS 5 6 6 R/W 6 5 5 E 7 8 8 DB0 8 7 7 DB1 9 10 10 DB2 10 9 9 DB3 11 12 12 DB4 12 11 11 DB5 13 14 14 DB6 14 13 13 DB7 ********* What can you do if you have already messed up by having your PIC board wired up the wrong way? Use TWO identical IDC cables. Connect them together by using two 7 pin rows of header pins, or if you don't have that handy, then insert short lengths of snipped resistor leads or #20 bare single strand wire into all 14 pins of one cable end, and then plug the other cable into the one with the wire pieces. Insert the two cables so that the side with pins 1&2 plugs into the other cable's side that has pins 1&2. This effectively re-routes the wires so that LCD header pin 1 goes to PIC board header pin 1, and the same with all the other wires. Fr. Thomas McGahee -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics