Which Microcontroller to use?

[haydar]

89at2051 programming

Hi
I am newbei on microcontrollers.
I need to build a pulse generator, which has four outputs. I attached a file that has parameters.
If you suggest me a controller, programmer kit, coding language, and anything that should be known by a "microcontroller idiot" please add comment.
Thanks in advance for your valuable comments.

 

[Slammer]

Any small mcu is OK for your application.
If you prefer 8051 architecture, the AT89S2051 is a perfect choice.
If you prefer AVR architecture, the ATtiny45 or ATtiny26 are good choices.
Both architectures have ISP capabilities and are supported by C compilers, development tools, etc....
Of course you can look also for similar PIC mcu.
Any MCU will make the job very well.

 

[dilan2005]

this kind of project can be done other than microcontrollers.but it depends on the appliction and how much accuracy do u want.

can be easily done on pic16f84
using non ending loop

or

cypress PSOC devices which have programmable blocks can have many PWMS as possible

or

can be implement on the FPGA for very accurate timing


please give us more information on application and how critical the voltages
your image is unclear to me. can u give more detail better description

Rgds
dilan

 

[vijaya_narayana]

u can use any type of micro controllers for atmel u can get cheap programmers and when u r using atmel the H/W cost can be reduced to minimum

 

[haydar]

this kind of project can be done other than microcontrollers.but it depends on the appliction and how much accuracy do u want.

please give us more information on application and how critical the voltages
your image is unclear to me. can u give more detail better description

Rgds
dilan

Hi
This will not be mass production. Therefore its cost is not important. If you suggest me very efficient, improvable (for example it may have a temperature sensor, or receiving data possibility. I may want to receive data. but these are not urgent) controller, it would be great.
My main concern is deadline. Implementation should be simple.
Voltage level is not so critical, it can be 9 or 11, but shoud not be more than this.
I want to control this with an intereface working on an XP platform.

Thank you very much to all.

 

[Slammer]

I suggest an AVR MCU. If you plan to make some extension (UART, more signals, etc) go with ATmega8.
It is faster than 89AT2051 and has much more memory for almost the same price. (It will be tricky to control 50usec pulses with 8051).
Buy an ISP programmer from Atmel or build one yourself (look for pony programmer), download avr-gcc and you are ready to start programming.

 

[dilan2005]

hi,

i need more infromation on the pules

1.is all 4 electordes pulse periods are same ?

2.what u want to actually control


3.Giver me a timing diagramme of 4 elctrode

ex: inputs to the microcontroller?

electrode 1 voltage
^
|
|
|
|
|******
| *
|_____*______________________________>t
| * *
| * *
| *********************
|
|
|
|

Duty cycle
TIme period

i need four sperate graph for each electorde

4. actually I WANT MORE INFORMATION of the project. the infomation u are given
is not suffcient.
if u can chat with me it's better through Gmail

write a private message to me in this fourm including ur gmail so i can chat with u

Rgds
dilan

 

[haydar]

hi,

i need more infromation on the pules

1.is all 4 electordes pulse periods are same ?

Yes, they are the same.

2.what u want to actually control

Pulse width, frequency, amplitude, and electrode combinations.

3.Giver me a timing diagramme of 4 elctrode

ex: inputs to the microcontroller?

electrode 1 voltage
^
|
|
|
|
|******
| *
|_____*______________________________>t
| * *
| * *
| *********************


Duty cycle
TIme period

i need four sperate graph for each electorde

Assume electrode 1 is +, electrode 2 is +, electrode 3 is 0, and electrode 4 is -.
Pulse width is 60 micro sec, period is 100 micro second. Magnitude is 8 volts, between +5 and -3

electrode 1 voltage
^
|
|
|
|5 V
|***************
|
|
|_______________60*********_______100___>t
|
|
|
|


electrode 2 voltage
^
|
|
|
|5 V
|***************
|
|
|_______________60*********100___>t
|
|
|
|



electrode 3 voltage is off, that is, no connection is done.



electrode 4 voltage
^
|
|
|
|
|
|
|_______________60*********100___>t
|
|
|***************
-3 V

 

[dilan2005]

do u need 4hz 1500hz continous change or in setps!


Ie

if u need frequcy of pwm like

4,5,6,7,8.............1549,1500

or

4,8,...............1448,1452


what is the pwm resuluation u want

in steps of 1
or steps of 16

Added after 26 minutes:

following is the basic idea


in pic using asmbling codes using looping the PWM is generated

this fed to anlog multiplexers which will do connect apprpriate voltages.
**broken link removed**

 

[haydar]

do u need 4hz 1500hz continous change or in setps!


Ie

if u need frequcy of pwm like

4,5,6,7,8.............1549,1500

or

4,8,...............1448,1452


what is the pwm resuluation u want

in steps of 1
or steps of 16

4,8,...............1448,1452 for freq. is great.

pwm resolution can be 16.

 

[dilan2005]

for programming 16f84a use microchip pic assembly?
as timing is critical

when we use 4Mhz crystal each assembly instruction takes 1us or 2us

i figure out do the timing this way
//====================
interupt handeler

ON INTERRUPT WE CAN CHANGE THE PWM PEREIOD AND dUTRY CYCLE AND
ELECTRODES POLARTIES

IN THE EXEXUTION OF INTERRUP HANDALER tHE pwm WILL sTOP

retie
==================
loop

in THIS NON ENDING LOOP WE CREATE THE PWM SIGNAL

go to loop
//================

DELEY
//==============================


THIS IS THE ONE RESPONSEIBLE FOR ACCURATE TIME GAPS

//============================


Do u need a sample assembley code ?
is it okey when the electrodes are off when we ares setting new PWM frequency Duy cycle and electrode pattern

 

[haydar]

Do u need a sample assembley code ?
is it okey when the electrodes are off when we ares setting new PWM frequency Duy cycle and electrode pattern

It would be great if you send it. I will try to write it with C.
It is not a problem.

thanks a lot.