AVR-Chat

I apologise upfront if this has been asked before - again and again etc.

I am a little confused about programming the target uC, as I have only
been working in simulators and the likes and in general just playing
around.

The side that confuses me the most, is the wiring of the pin to the uC
- is it as straight forward as MOSI to MOSI, MISO to MISO, SKT to SKT,
and RST to RST, or is there more to it?

During my Google searches I have found a number of programming board
circuits that are quite confusing as some use straight out wire,
resistors, transistors, diodes or a combination from the interface to
the chip.

The only thing that I do not find confusing, the board needs to have
between 3.3v to 5v.

It depends on the processor, even within the AVR family.

Some share programming with the SPI port. Some have a
separate set of pins for programming. You have to look at
the data sheet. Normally, it is under "Memory Programming".
A few of the really low pin count devices ONLY have
DebugWire.

Jim Wagner

On Thu, 15 Nov 2007 03:32:06 -0000
 "warp_kez" <warp_kez@hotmail.com> wrote:
> I apologise upfront if this has been asked before - again
> and again etc.
> 
> I am a little confused about programming the target uC,
> as I have only
> been working in simulators and the likes and in general
> just playing
> around.
> 
> The side that confuses me the most, is the wiring of the
> pin to the uC
> - is it as straight forward as MOSI to MOSI, MISO to
> MISO, SKT to SKT,
> and RST to RST, or is there more to it?
> 
> During my Google searches I have found a number of
> programming board
> circuits that are quite confusing as some use straight
> out wire,
> resistors, transistors, diodes or a combination from the
> interface to
> the chip.
> 
> The only thing that I do not find confusing, the board
> needs to have
> between 3.3v to 5v.
> 

---------------------------------------------------------------
The Think Different Store
http://www.thinkdifferentstore.com/
For All Your Mac Gear
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--- In AVR-Chat@yahoogroups.com, "warp_kez" <warp_kez@...> wrote:
> - is it as straight forward as MOSI to MOSI, MISO to MISO,
> SKT to SKT, and RST to RST, or is there more to it?

In a word, yes.

This is an SPI interface that has a master (the programmer) and a 
slave (the device being programmed).  The acronym MISO means Master In 
Slave Out while MISO means Master In Slave Out.  That's why you 
connect like-named signal lines together.  The clock line, SCK, is 
output by the master and input by the slave.  Likewise for Reset.

Don Kinzer
ZBasic Microcontrollers
http://www.zbasic.net

At 02:32 PM 15/11/2007, you wrote:
>The side that confuses me the most, is the wiring of the pin to the uC
>- is it as straight forward as MOSI to MOSI, MISO to MISO, SKT to SKT,
>and RST to RST, or is there more to it?

Almost correct except for the reset pin. Have a look at the STK500
docs in Studio, it shows how to wire up the connector.

It would also help if you tell us which programmer you are using
and which chip, not all chips use Miso and Mosi.

Regards

John Samperi

********************************************************
Ampertronics Pty. Ltd.
11 Brokenwood Place Baulkham Hills, NSW 2153 AUSTRALIA
Tel. (02) 9674-6495       Fax (02) 9674-8745
Email: john@ampertronics.com.au
Website  http://www.ampertronics.com.au
*Electronic Design * Custom Products * Contract Assembly
********************************************************

Its not quite that simple.  A good book that takes you through all of  
this kind of stuff is Designing Embedded Hardware by Catsoulis.  He  
talks about the main pins on a uC and has several sample hardware  
designs that he explains along with the software to drive them.

A good place to get started is one of the boards packaged with a  
compiler and experiment kit.

CCS makes some nice ones based around the PIC processor, but they're  
not cheap.  You'll be into it for several hundred bucks between the  
hardware and compiler.  The nice thing about them is they include a  
tutorial that shows you how to use each portion of the uC in detail  
along with some parts and wires to try other stuff.

I'm sure someone makes something similar for the AVR, but I don't  
know of one off hand.

On Nov 14, 2007, at 7:32 PM, warp_kez wrote:

> I apologise upfront if this has been asked before - again and again  
> etc.
>
> I am a little confused about programming the target uC, as I have only
> been working in simulators and the likes and in general just playing
> around.
>
> The side that confuses me the most, is the wiring of the pin to the uC
> - is it as straight forward as MOSI to MOSI, MISO to MISO, SKT to SKT,
> and RST to RST, or is there more to it?
>
> During my Google searches I have found a number of programming board
> circuits that are quite confusing as some use straight out wire,
> resistors, transistors, diodes or a combination from the interface to
> the chip.
>
> The only thing that I do not find confusing, the board needs to have
> between 3.3v to 5v.
>
>
>
>
> Yahoo! Groups Links
>
>
>
>

--- In AVR-Chat@yahoogroups.com, John Samperi <samperi@...> wrote:
>
> Almost correct except for the reset pin. Have a look at the STK500
> docs in Studio, it shows how to wire up the connector.

If I am reading the documentation correctly, applying 12v with a pull
up resistor (> 4.7k) is required.

Viewing the circuit for the PonyProg SIProg for 40pin AVRs is now
starting to make a bit more sense.
 
> It would also help if you tell us which programmer you are using
> and which chip, not all chips use Miso and Mosi.

I am looking at the PonyProg ISP or the AVR-PG2b programmers.

Though, I am thinking it may be easier to buy the STK500.

At 12:44 PM 18/11/2007, you wrote:
>If I am reading the documentation correctly, applying 12v with a pull
>up resistor (> 4.7k) is required.

Not really, only a few small chips will need the 12V, but you let
the programmer do that. The vast majority of AVR do no need that.

>I am looking at the PonyProg ISP or the AVR-PG2b programmers.
>
>Though, I am thinking it may be easier to buy the STK500.

If you want to save yourself possible headaches go for the STK 500.
It works directly from studio and it is supported by Atmel.

Regards

John Samperi

********************************************************
Ampertronics Pty. Ltd.
11 Brokenwood Place Baulkham Hills, NSW 2153 AUSTRALIA
Tel. (02) 9674-6495       Fax (02) 9674-8745
Email: john@ampertronics.com.au
Website  http://www.ampertronics.com.au
*Electronic Design * Custom Products * Contract Assembly
********************************************************

At 04:45 PM 16/11/2007, you wrote:
>A good place to get started is one of the boards packaged with a
>compiler and experiment kit.

If you are into C then you can't go wrong with a
Butterfly and a C book from:
http://www.smileymicros.com/


Regards

John Samperi

********************************************************
Ampertronics Pty. Ltd.
11 Brokenwood Place Baulkham Hills, NSW 2153 AUSTRALIA
Tel. (02) 9674-6495       Fax (02) 9674-8745
Email: john@ampertronics.com.au
Website  http://www.ampertronics.com.au
*Electronic Design * Custom Products * Contract Assembly
********************************************************