Guide Make your own USB LCD controller!

Hi guys.

Is the Hex code (18f4550 version) compatible with 44-Pin TQFP package?:



If it's not compatible, could I please have the code of the PIC in order to compilate it for this package?.

¿ Is it a real USB device or a CDC RS232 emulation?


Thanks.

 

simon: Package makes no difference. However, apparently the 4550 hex doesn't work... wait until one of the guys working on it has something working...

Jens: good job, that's three of us working with linux no problem! Fantastic. I still can't get it to work in 64-bit Vista though, which is annoying.

Jens and Patrik:
3: Yes, a plugin is the way to go, good idea!
6: The Microchip software is totally royalty free. Yes, I'd agree on the different hex files for different functionality.
9: That's a cool idea but I don't know if it's possible. It's definately too complicated for me to manage. A much simpler approach would be to just forward data from the PIC's serial port to the virtual one on USB and let LCDSmartie deal with it.

Yes, we'd need collaboration, and I'm quite busy at the moment... I don't think a sourceforge project would be possible though: how does CVS work with the Microchip C18 compiler?

Thanks

ch424

 

With the 18f4550 hex that i made is simply the 18f2550 code with the 2550 references changed to 4550 to make it compile.

As for adding the config bits. CH424, did you have the bits added to the source yet? if so can i get the updates pls. Once i have that i will create another 18f4550 .hex and see how it goes.

Also i have a couple of the SM 18f4550 ic's coming to me. so hopefully i can give it a test myself. I just hope that i can get em soldered to a board.

Also If anyone is doing the board layout still, i would like to see a ICSP port to allow for reprogramming of the chip. Would ne a nice addition.

thanks

Scorpia

 

Hi guys.

I have revised the code to adapt it to the PI184550. (linker, includes, etc).
I have compiled the code (including the configuration bits) and have burned the HEX in the microcontroler (PDIP package) and the PC perfectly recognizes it like a new port COM.
Tomorrow I will search for my old LCD and I will mount it according to the scheme to see if smartie works with It. If everything has gone Well, I'll upload hex file and details.

Thanks for all Alex and Scorpia.

PD: Sorry for my bad English.


Mounted on a PICDEM FS USB cloned board

 

I can't test it because I don't find my old LCD.

Can anybody test the hex with a pic18f4550?

download hex code

 

Nice work.

i hope someone gets it to work with the LCD.

Having lots of I/O would be a good thing if we want to add buttons etc.

Scorpia

 

Hi, I've gotten the LCD and these are my tests results:

• PIC18F2550 with ch424's hex: Windows recognizes CDC device, smartie OK.
• PIC18F4550 with scorpia's hex: Windows not recognizes CDC device, so no tests with smartie.
• PIC18F4550 with my hex: Windows recognizes CDC device, smartie crashes
• PIC18F4550 with ch424's hex (PIC18F2550 version) : Windows recognizes CDC device, smartie crashes

I don't understand what is the problem with PIC18F4550 uC.

Any suggestion?

 

I've used the PIC18F4550 in various projects many times without problems - having not seen the code I can't help you with what's wrong, but I'd make sure your problems don't lie with the hardware first. (there should only be a few changes and additions to make in software when transferring from the PIC18F2550). Do you have a clear picture of your set up?

edit: Regarding people's problems with the rotary encoders - Am I to understand you're just sending a character depending on the state of the encoder. If that is the case it will obviously cause problems! It'll be very easy for the system to mistake rotation in one direction as a pulse in the other direction or rotation at high speed to become garbled. You're far better off debouncing and decoding the grey code on the PIC then sending a character relating to one detent in a particular direction of rotation.

 

Have you tried talking to the LCD with hyper terminal? it looks like a serial port so you should be able to type straight to the screen. let us know what happens.

also i think i hav e found the simplest programmer yet.
check http://artjoy.narod.ru/eng/index_eng.html

Scorpia

 

LVP only on that programmer though, so you lose PORTB's full 8 bits for good.

 

loose port b for good?
does it not allow you to use RB5,6,7 after its removed from the programmer?

 

You can't use PGM (RB5?) - it has to be permanently tied low

 

yuck,

dont like that then.

Also on a slightly different note, check http://eegeek.net/content/view/56/32/

looks like it adds a serial number to the USB code in the pic to allow windows to track which serial port its plugged into. should stop the driver reinstalling every time you change USB ports. I guess the only downside might be if someone is running 2+ devices in the system as they would need different serial numbers.

Scorpia

 

Good news: It works !!

For PIC18f4550
HEX + SCHEME + INF

Please, note this scheme doesn't include GPOs.


ch424, Scorpia, SteveyG thanks for your help.

PD: ch424, I'll send you an email with the MPLAB proyect for the 4550.

Regards from Spain.

 

Fantastic,

PIC's thanks

scorpia

 

I got my LCD and Pic18F2550-I/SP from Australia today. I have some question.
RV2 4k7 it mean rheostat? and if i can't find X1 4Mhz form electric market so where i can find from old electric board.
Thanks for your help.

 

Yep, RV2 4k7 is a rheostat, well a potentiometer. See http://en.wikipedia.org/wiki/Rheostat for more info on that
Well it's hard to know where to find the correct value of a crystal. I've actually never found any 4Mhz while scavenging old circuitboards. and don't forget the capacitors for the crystal. 2:nd best alternative is an oscillator and 3:rd is the one below.
It is possible to make an equivalent circuit with an inductor, capacitor and resistor (See Wikipedia for more info) But beware, it can be quite hard to make.

 

Thanks for you help, guys

 

Nice with a working 4550-hex, can't wait to try it!
nhenhophach: That looks good, the difference between 4k7 and 5k won't matter. The (2S)C1815 should work, another that comes to mind is BC547 or BC548 (common in Sweden).
As for the crystal I actually captured a bunch of them from old boards, mainly old televisions if I remember correctly. Often they are mounted with fitting capacitors nearby. I actually use one of these crystals in my current LCD-2550-setup.
ch424:
A SF-project of course is nice, but I don't know if it works. Maybe begin with a simpler approach, setting up a Todo list and assign different tasks for different members?

Something like this:
1 - Redesign board and code for 6 buttons - assigned to:
2 - LCDSmartie plugin - assigned to:
3 - Set up a wiki for info - assigned to:
4 - RF/IR-receiver - assigned to:
5 - ? - assigned to:

As for the RF-receiver: I have been thinking for a while about collecting signals from my RF-devices with the computer. A 2550 would be ideal for that. Will see if I can work something out that might be merged to the code.

 

Something wrong with me. Only get that, sorry for bad quality



I will do again tomorrow but afraid my PIC dead.