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Slovak
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Le téléchargement nécessite un accès à la bibliothèque YouScribe Tout savoir sur nos offres
8
pages
Slovak
Documents
Le téléchargement nécessite un accès à la bibliothèque YouScribe Tout savoir sur nos offres
Contents
About this Tutorial .......................................................................................................................... 2
Important Information .................................................................................................................... 2
Create Codevision Project ............................................................................................................... 3
Include .H and .C files in CodeVision ............................................................................................... 6
Sample .H File .................................................................................................................................. 7
Sample .C File ... 8
SJVE Page 1 of 8
About this Tutorial
This tutorial will guide you on how to create a project in CodeVision. Furthermore, it explains how to
burn the code onto an Atmega chip using STK500 board and program the microcontroller to output
serial data that you can read to and from the microcontroller. Finally, there is a section that explains
how to setup header files in CodeVision
Important Information
1. The clock on the STK500 kit is 3.686Mhz
The clock on the PCB Kit is 16.000Mhz
2. Do not change the fuse bit settings in CodeVision unless you know what you are doing.
Changing fuse bit setting can disable the Atmega microcontroller
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Selecting the chip type lets you choose
features of the chip. You must select
Create Codevision Project the correct frequency of the Atmega
otherwise many functions like UART
and delay function calls will not work as
1. Open CodeVision
intended
2. Click File New
4. In the next figure, user can choose the
settings for UART. This will enable the
use of printf and scanf statements.
UART enables you to perform
input/output functions for the Atmega
microcontroller and it is also useful to
debug code.
3. After clicking Yes in the previous
prompt, you can now use CodeVision to
automatically generate template code
for Atmega microcontroller.
5. Select File Generate, Save and Exit
6. You can now name your project files
and save them into a project folder.
7. CodeVision will generate the code and
now you can burn the code into the
Atmega, but first, a few settings need to
be changed.
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8. Click on Project Configure and go to
the C Compiler tab
9. First, if you wish to display floating
point numbers using printf(“%f”,
myfloat); then you need to enable this
feature. Do not enable this feature
unless required because it takes a lot of
code memory space. Under the
(s)printf features, select float,width,
precision if needed, otherwise leave it
alone.
Normally, you do not need to Verify the
code so deslect Verify option. Program
Fuse Bit(s) is also not needed because
this can change the way Atmega starts
up using various clock options.
Atmega’s come programmed to use
external clock, which is exactly what the
PCB kit and the STK500 uses so do not
change this unless you know what you
are doing.
11. Click OK
12. Scroll down towards the bottom of the
code and observe that your entire code
10. Now browse to After Make tab. Check
needs to be within the while(1) loop.
the “Program the Chip” option and
This is an infinite loop and the
choose the options described by the
microcontrollers must have one infinite
next figure:
loop otherwise they it execute code
once and stop working. Add the
following code inside the while loop:
“printf(“test\n”);
delay_ms(100);
Adding the delay is necessary otherwise
the microcontroller outputs data so fast
that the PC buffer will overflow for the
incoming serial data and your computer
may freeze while trying to read the data
from the serial buffer chip.
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13. Go to the top of the code and add this PD0/PD1 to RX/TX and connect serial
ndstatement: “#include <delay.h> cable to the 2 DB9 port.
14. Go to Settings Programmer and 21. You should now see the microcontroller
ensure that the COM port you chose is outputting data.
indeed the COM port connected to
STK500 programming port (next to the
DC power jack)
15. Press Shift+F9 and then select Program
the Chip option
16. The code is ready and microcontroller is
now printing printf statements, now
you need to connect the serial cable to
see the output.
17. Download “Hercules Setup” by
searching for it in google.
18. Open up Hercules Setup and go to the
Serial Tab. Choose the COM port that is
available. This could be the same as the
Programming COM port if you do not
ndhave a 2 COM port in your computer.
Choose the speed in bps, which must be
the same as the one in step 4. Click
OPEN to open the COM port.
19. Nothing should print at this point
because you need to connect the serial
cable to which the PCB kit of STk500 is
outputting data to.
20. For the PCB kit, read the manual and
connect RX/TX and serial cable to the
DB9 connector. For STK500, connect
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Include .H and .C files in CodeVision
Many times,