Please help with calculator project..

[scs83]

pic18 help calculator code

Hi,

I am now doing a project based on this website

https://instruct1.cit.cornell.edu/courses/ee476/FinalProjects/s1999/sam

The chip that I used is exactly the same with the website which is Atmel 8515. After connecting the circuit, my LCD only shows black boxes. Anybody can help me with this?

I have no idea what a STK500 is. Is it compulsory to use it? I assembled the code in the website using AVR Assembler 1.30 then downloaded the code into the chip using ALL-11 Universal Programmer.

As for the circuit diagram based on the website's description, the numerical keypad is connected to port D and the function keypad is connected to port B. Both LCDs are given a common data bus and then driving them with their own set of control lines. I am using 4 Mhz crystal with 30pF capacitors. Is there anything which I missed out?

I really hope somebody can read through the website and give me some
assistance because I have really no idea on what to do now. I need
some help fast!

Thanks.

 

[adidex]

lcd avr black boxes

hello
the STK500 is a development board for AVR microcontrollers, if you build your own hardware and have an AVR programmer you don't have to use it.
the lcd shows black boxes becouse the LCD chipset is not initialise. Most LCD's use an HD44780 compatible controller, so your lcd allmost certainly uses such a controller, and you can find alot of infos about it.
the best thing to do is to split the project in smaller pieces, first of all make the lcd print some text, and after that you should work on the keyboard part, becouse you might have to put some pull-ul resistors there to make it work, or activate the internat pull-ups in the microcontroller .
Another possibility is that you didn'd supply the negative tension for the microcontroller (check the LCD's datasheet, usually needs -5V). For negative tension conversion you might use an TC7660 .
For the lcd control, you can find alot of information (and ready-made projects) on www.avrfreaks.net .
If you take it step by step we might be able to help you, but i guess nobody would make your design from scratch for you, becouse after all, it is your project.

Adi.

 

[scs83]

avr calculator project

Hi,

Right now I am testing the LCD based on an example. Below is the attachment. But I still get the black boxes. When I use 16x1 LCD, I will get 8 black boxes while if I use 16x2 LCD, I will get 16 black boxes. I have connected the circuit exactly the same and done the procedure. I really dony know where have I gone wrong.

About my project, I found out that my chip actually runs at 8Mhz but I was using 4Mhz all along. Is this the cause?

Thanks.

 

[adidex]

calculator project circuit

Sorry, i ca't see the pdf, not enough points ...
You can send the schematics and program on my e-mail adress and i will take a look, i had several projects with AVR's + LCDs, so i will try to help ...
If you have an 8mhz AVR, it can run from 0 to 8Mhz max, so if you use an 4Mhz Crystal is OK ...
Are you using an AT90S8515 or ATMega8515 ? ATMegas have several fuse settings that can cause you trouble (since you use an old programmer i guess you have an AT90S8515 ...)
The LCD will stop showing blanks only after you send the hole initialisation sequence, that's the hard part, after you print some characters on in everything would be alot easier ..

Adi

 

[scs83]

Hi,

Can you try to download the file again? You have 3 points now, hope it is enough.I dunno what's ur email. I am using AT90S8515 8PI by the way.

 

[adidex]

I downloaded the pdf file, but i tought that was the project thay you're working on ) . I don't need docs for controlling LCDs, i have alot of them ....
I changed my profile yesterday so anybody can send me e-mails, so click on the profile button (at the buttom of my message), and then click on e-mail, hope this works, 'cose i'm new in this web-board ... Or you can send on adi2san (at) yahoo (dot) com - you'll understand .
So send me if you can your assembler program and at least the detailed uC to LCD interconnections descriptions, to take a look at it ...
I am currently developind an application that incorporates a 2*16 LCD connected on an ATMega162 (in C) , so if you can wait some more days (10-15) i could test your program on my board (just modify it a little bit to work on my controller, the biggest part of the program should be the same) ...

Adi.

 

[scs83]

Hi,

Ok, I will send it to you as soon as possible. I need to sort out the program code first. Dont worry I can wait the 10-15 days as long as you can test it out for me. Thanks.

 

[adidex]

Take a look at this link :
**broken link removed**
It's an serial LCD (data sent through RS232 is displayed on an 16*2 lcd). If you strip off the serial routines you end up with an LCD Interface . Or you can just use the same circuit and test the hole project ...
It;s written in assembler, and works on 2313 nd 8515 (different code for them, see at the top). Just check with your LCD to see if the VO pin needs 0 to 5V, or 05 to 0V.

Adi

 

[Fragrance]

Hi,

I am now doing a project based on this website

h**p://instruct1.cit.cornell.edu/courses/ee476/FinalProjects/s1999/sam

The chip that I used is exactly the same with the website which is Atmel 8515. After connecting the circuit, my LCD only shows black boxes. Anybody can help me with this?

I have no idea what a STK500 is. Is it compulsory to use it? I assembled the code in the website using AVR Assembler 1.30 then downloaded the code into the chip using ALL-11 Universal Programmer.

As for the circuit diagram based on the website's description, the numerical keypad is connected to port D and the function keypad is connected to port B. Both LCDs are given a common data bus and then driving them with their own set of control lines. I am using 4 Mhz crystal with 30pF capacitors. Is there anything which I missed out?

I really hope somebody can read through the website and give me some
assistance because I have really no idea on what to do now. I need
some help fast!

Thanks.

hi

just get demoversion of proteus from labcenter web page and you get three diffrent types of calculators in it based on c51 and 8051 pic based and pic18 based calculator, the pic18 calculator code is written in c so you can easlly port it to other varrient of controller as well

http://www.labcenter.co.uk

 

[scs83]

Hi,

I have already sent to your email account adi. Can you check if you have received it?