Please advice which chip is suitable and need some idea

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I need 8 inputs and 4 outputs and 3 potentiometer input with 8 bit (or 6 bit)

1)if input 3 is ENABLEd for 1 and 2 input, (these are 500 Hz PWM) transferred to 1 and 2 output (like a switch)
2) two potentiometers control 2 timer, one for ENABLE function and other for 1st output
3) other potentiometer controls PWM signal for duty ratio controller, say if more than 50% pwm, it limits at %50 (adjustabe with pot3)

Which chip is suitable for this project and give some idea for the functions abowe especially for(3). PWM is free running
Thank you

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The atmega2560 will do for sure, but why not check the atmel parametric table ? ( or is this still broke ??? )

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meslomp wrote:
The atmega2560 will do for sure, but why not check the atmel parametric table ? ( or is this still broke ??? )

Is it huge chip?
My limitations are:
DIP package
suitable with STK500 developing board
Thanks

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Download the atmel parametric table as an excel file. Takes a couple minutes to load the table. Look for AVRs with number of inputs >- to what you need, a/d channels >= to what you need, etc. You have a fairly simple spec there, so I think just about any amount of flash from 4K to 256K would be ok. Similarly, you only need a couple of bytes of ram for variables, so even the small AVRs with 1k of ram are ok. Will you use c? Which compiler? (I'll help you if you use the imagecraft compiler)

Imagecraft compiler user

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bobgardner wrote:
Download the atmel parametric table as an excel file. Takes a couple minutes to load the table. Look for AVRs with number of inputs >- to what you need, a/d channels >= to what you need, etc. You have a fairly simple spec there, so I think just about any amount of flash from 4K to 256K would be ok. Similarly, you only need a couple of bytes of ram for variables, so even the small AVRs with 1k of ram are ok. Will you use c? Which compiler? (I'll help you if you use the imagecraft compiler)

I cant find "working" parametric table in excel,
link please

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I got it to dl the excel version once. I guess they are improving it. Basically any avr will do this job. Something like a mega168. Has input and output ports, a/d, uart, ram, flash rom, everything you need.

Imagecraft compiler user

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I tried downloading it, and my opinion is that the parametric download is a mess.

The file has an extension of xls. But, its NOT. Its full of html and xml. The only thing (on my Mac) that I can open it with is NeoOffice. Then I have to carefully select all the columns except some garbage to the far right, then copy and paste it into ANOTHER database program. If I try to save it direct from OpenOffice, it ONLY saves as an html file readable, but not editable, in a web browser. It would be far simpler if it came as a straight up xls file or even a tab-delimited text file.

Jim

Jim Wagner Oregon Research Electronics, Consulting Div. Tangent, OR, USA http://www.orelectronics.net

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Quote:

I tried downloading it, and my opinion is that the parametric download is a mess.

???

I don't see a bit of HTML or XML. Excel2003 swallowed it up without apparent problems. A small excerpt, cut-and-paste

ATmega8	8-bit	Yes	8	included	Yes	Yes	512	1K	no	Yes	2	1	2-Jan	12/-	3	no
ATmega8515	8-bit	Yes	8	included	Yes	Yes	512	512	no	no	1	1	2-Jan	16/-	3	no

For OP's purposes, though, it will be annoying at best that Mega or Tiny has to be selected and you only get one or the other table.

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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1 of the 20+ pin tinys can do it or a mega48. Just count total pins / peripherals you need and see which MCUs are in range. You give ideas for functions 1st and you'll get help for THAT. If you can't, you may not be ready for this ( relatively basic ) app.

Check out the PWM / ADC tutorials in that forum.

1) Studio 4.18 build 716 (SP3)
2) WinAvr 20100110
3) PN, all on Doze XP... For Now
A) Avr Dragon ver. 1
B) Avr MKII ISP, 2009 model
C) MKII JTAGICE ver. 1

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which compiler do you use ? or ASM.
If you want to use a stk500 board just get one DIP 40 chip (something like a mega16) and get it to work, then you can see code size (and RAM use) and find out what you need.
How fast is the response time for 3) ? and what is the needed PWM speed ?

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Here is what I see in Apple "Numbers" (fully capable of opening a standard .xls file). This is a screen capture of the window. Look carefully, you will see a standard html preamble at the top.

Jim

Attachment(s): 

Jim Wagner Oregon Research Electronics, Consulting Div. Tangent, OR, USA http://www.orelectronics.net

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Quote:

Look carefully,

I'm staring... :twisted:

I opened up the file with WinHEX and do see a bit of HTML at the top.

As mentioned, I have no trouble opening the file with Excel2003. But you said that

Quote:

Apple "Numbers" (fully capable of opening a standard .xls file).
so then I can only conclude that since Microsoft's Excel which uses the .XLS extension and is able to open the file, isn't really doing it correctly 'cause another app doesn't know how to open the file. But you said it is fully capable. No wonder old guys get confused.

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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sparrow2 wrote:
which compiler do you use ? or ASM.
If you want to use a stk500 board just get one DIP 40 chip (something like a mega16) and get it to work, then you can see code size (and RAM use) and find out what you need.
How fast is the response time for 3) ? and what is the needed PWM speed ?

Thak you very much
1. I am planning to use Bascom Avr
2. PWM is 500Hz and I want to measure in 8 bit resolution

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ka7ehk wrote:
The only thing (on my Mac)...
Jim

Hi Jim,

Get a real computer.

and now a message from our sponsor

Way off topic: Are you going to SEA-PAC?

returning to regular programming

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Larry - W7PAN

P.S. I'm not trying to start a flame war - just kidding around.

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[ot] Will try to get to Sea-Pac this year. Its been several years since I made it up there. [/ot]

Jim

Jim Wagner Oregon Research Electronics, Consulting Div. Tangent, OR, USA http://www.orelectronics.net