AVR-Chat

I designed a board for my railroad signaling project (outdoor, ride-on,
1/8th scale) around the ATMega32A and so far it has worked out well running
my multi-node CAN network based system.  

One of the regrets I have is that I did not take the advice of those that
recommended that I go with an ATxxx-CAN device rather than a non-CAN device
and an external CAN controller (I chose the MCP2515).  At the time I was not
sure that CAN would work for me so I wanted to keep my network options open.
CAN has been working great and I wish I was interfacing with an internal CAN
controller rather than having to deal with the extra SPI communications
layer … live and learn :-)

My other regret Is that I violated a rule I should have known - use the
device with the largest reasonable amount of memory available to reduce the
chances of "hitting the wall" in development.  Even though this was my first
real microcontroller-based design, I should have known better ... (see my
signature line!).

My board is designed around the ATMega32A and I am about at its memory
limits (with optimization turned on) and I have more features to add
(naturally).  I would like to upgrade to the largest compatible processor
that:
- 5v supply
- TQFN-44 package

Pins/peripherals I'm using (from memory without detail checking of the
code):
- 8 A/D inputs
- SPI
- TWI
- 1 UART (diag & monitoring)
- JTAG
- OC2
- INT2
- AREF
- 6 general I/O
- Timers 1&2
- 14.7456 Xtal
- Watchdog

I have checked the data sheets and it looks to me like I can choose from the
following:

ATMega644, 644P, 644PA, 644A
ATMega1284 & 1284P

Mouser does not seem to stock the ATMega1284x in TQFN-44 but DigiKey stocks
the ATMEGA1284P-AU-ND which would seem to fit the bill.

For my use is the ATMEGA1284P-AU-ND pin and software (with appropriate
changes in defines, etc.) compatible the ATMEGA32A-AU or am I missing
something?

Thanks in advance for any help you can provide ...
 
Cheers,

Chuck Hackett
"Good judgment comes from experience, experience comes from bad judgment"
7.5" gauge Union Pacific Northern (4-8-4) 844
http://www.whitetrout.net/Chuck

On Jan 29, 2012, at 11:09 AM, Chuck Hackett wrote:

> My other regret Is that I violated a rule I should have known - use the
> device with the largest reasonable amount of memory available to reduce the
> chances of "hitting the wall" in development. Even though this was my first
> real microcontroller-based design, I should have known better ... (see my
> signature line!).
> 
> My board is designed around the ATMega32A and I am about at its memory
> limits (with optimization turned on) and I have more features to add
> (naturally). I would like to upgrade to the largest compatible processor
> that:
> - 5v supply
> - TQFN-44 package
> 
> Pins/peripherals I'm using (from memory without detail checking of the
> code):
> - 8 A/D inputs
> - SPI
> - TWI
> - 1 UART (diag & monitoring)
> - JTAG
> - OC2
> - INT2
> - AREF
> - 6 general I/O
> - Timers 1&2
> - 14.7456 Xtal
> - Watchdog
> 
> I have checked the data sheets and it looks to me like I can choose from the
> following:
> 
> ATMega644, 644P, 644PA, 644A
> ATMega1284 & 1284P
> 
> Mouser does not seem to stock the ATMega1284x in TQFN-44 but DigiKey stocks
> the ATMEGA1284P-AU-ND which would seem to fit the bill.
> 
> For my use is the ATMEGA1284P-AU-ND pin and software (with appropriate
> changes in defines, etc.) compatible the ATMEGA32A-AU or am I missing
> something?
> 
> 
I hit the wall using the ATMega 32 (on a model railroading project), went looking and chose the ATMEga1284P.  Software and hardware wise it was a drop in replacement.  The only thing I had to do to use the new chip was change the settings in my make file.  

The 1284 has more RAM, Flash and EEPROM and it has an additional timer and serial port.  In that project I did make use of the additional timer but not the serial port.

I don't know if the 1284 you are looking at is pin compatible with the 32 you are using but I suspect it is.

When I started using the AT AVRs I had settled on a few parts to use.  I hadn't looked around since then and wasn't aware of the 1284.  My biggest pet peeve is the large number of parts and the trouble of selecting one from that pool.  I just wish I had this sort of problem with other things.
> 
> 



[Non-text portions of this message have been removed]

If you post the c source and state that " No one can reduce this program by 10%", you will have a half dozen edits that reduce the program size by 10% in a couple of hours.

-----Original Message-----
From: Chuck Hackett <egroupscdh@up844.us>
To: AVR-Chat <AVR-Chat@yahoogroups.com>
Sent: Sun, Jan 29, 2012 3:57 pm
Subject: [AVR-Chat] Need confirmation on ATMega upgrade path


I designed a board for my railroad signaling project (outdoor, ride-on,
/8th scale) around the ATMega32A and so far it has worked out well running
y multi-node CAN network based system.  
One of the regrets I have is that I did not take the advice of those that
ecommended that I go with an ATxxx-CAN device rather than a non-CAN device
nd an external CAN controller (I chose the MCP2515).  At the time I was not
ure that CAN would work for me so I wanted to keep my network options open.
AN has been working great and I wish I was interfacing with an internal CAN
ontroller rather than having to deal with the extra SPI communications
ayer 
 live and learn :-)
My other regret Is that I violated a rule I should have known - use the
evice with the largest reasonable amount of memory available to reduce the
hances of "hitting the wall" in development.  Even though this was my first
eal microcontroller-based design, I should have known better ... (see my
ignature line!).
My board is designed around the ATMega32A and I am about at its memory
imits (with optimization turned on) and I have more features to add
naturally).  I would like to upgrade to the largest compatible processor
hat:
 5v supply
 TQFN-44 package
Pins/peripherals I'm using (from memory without detail checking of the
ode):
 8 A/D inputs
 SPI
 TWI
 1 UART (diag & monitoring)
 JTAG
 OC2
 INT2
 AREF
 6 general I/O
 Timers 1&2
 14.7456 Xtal
 Watchdog
I have checked the data sheets and it looks to me like I can choose from the
ollowing:
ATMega644, 644P, 644PA, 644A
TMega1284 & 1284P
Mouser does not seem to stock the ATMega1284x in TQFN-44 but DigiKey stocks
he ATMEGA1284P-AU-ND which would seem to fit the bill.
For my use is the ATMEGA1284P-AU-ND pin and software (with appropriate
hanges in defines, etc.) compatible the ATMEGA32A-AU or am I missing
omething?
Thanks in advance for any help you can provide ...

heers,
Chuck Hackett
Good judgment comes from experience, experience comes from bad judgment"
.5" gauge Union Pacific Northern (4-8-4) 844
ttp://www.whitetrout.net/Chuck



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[Non-text portions of this message have been removed]

> From: bobgardner@aol.com
> 
> If you post the c source and state that " No one can reduce this program by
> 10%", you will have a half dozen edits that reduce the program size by 10%
> in a couple of hours.

Sure, any good engineer loves a challenge :-)

I my early professional career (mid 70's) I can remember working for days to get one more byte of code space in an intelligent (?) terminal that had 4k of memory, 2k of which was dedicated to the display.  We even did unthinkable things like self-modifying code to save space (hangs head in shame ...) ...

Anyone else ever work with Incoterm terminals?  You might remember the rather large blue, metal cased terminals that United Airlines ticket agents once used.  They we Incoterm 1020's I believe (boy, that's reaching way back in the databanks!).  If the agent mad you mad all you had to do was reach down and press the little red "boot" button and she was out of commission for quite awhile.

Wow, amazing what you can find with Google.  Here's a page that talks about it and United Airlines: http://www.vintagecomputing.com/index.php/archives/33

Back to the world of today:  At the moment I'm running more into a RAM limit than a flash limit on the ATMega32A.  I expect to add significant functionality down the road which will eventually consume more flash ... and I learned my lesson ... go big! :-)
 
Cheers,

Chuck Hackett
"Good judgment comes from experience, experience comes from bad judgment"
7.5" gauge Union Pacific Northern (4-8-4) 844 http://www.whitetrout.net/Chuck

> From: Clark Martin
> ....
> I hit the wall using the ATMega 32 (on a model railroading project), went
> looking and chose the ATMEga1284P.  Software and hardware wise it was a
> drop in replacement.  The only thing I had to do to use the new chip was
> change the settings in my make file.

Thanks Clark, that's what I needed to know from someone who's "been there"
...

> The 1284 has more RAM, Flash and EEPROM and it has an additional timer
> and serial port.  In that project I did make use of the additional timer
but
> not the serial port.

I doubt if I could use the extra serial port because I'm using almost all 44
pins now (and the PCBs already produced).

The additional timer may come in handy though.

> I don't know if the 1284 you are looking at is pin compatible with the 32
you
> are using but I suspect it is.

I brought up the PDFs side by side and they appear to have compatible
pinouts unless I missed something.

Thanks for the feedback ...
 
Cheers,

Chuck Hackett
"Good judgment comes from experience, experience comes from bad judgment"
7.5" gauge Union Pacific Northern (4-8-4) 844
http://www.whitetrout.net/Chuck

On Jan 29, 2012, at 4:01 PM, Chuck Hackett wrote:


> 
> I my early professional career (mid 70's) I can remember working for days to get one more byte of code space in an intelligent (?) terminal that had 4k of memory, 2k of which was dedicated to the display. We even did unthinkable things like self-modifying code to save space (hangs head in shame ...) ...
> 

A long time ago when I was in high school we had these HP programmable calculators (big suckers, the size of a desktop computer).  They had mag card readers (for program storage) and a plotter.  I wrote a simple warship game for it.  It used all available memory (the data registers alternatively held program instructions.  Getting it to all fit took quite a bit of shoehorning.  I haven't thought of that program in a long time.

[Non-text portions of this message have been removed]

At 11:01 AM 30/01/2012, you wrote:
>add significant functionality down the ROAD

Surely you mean "down the TRACK"....... ;-)


Regards

John Samperi

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

Metaphors vary with culture. I will not presume which locals have "culture" and which do not.

Jim Wagner
Oregon Research Electronics

On Jan 29, 2012, at 5:24 PM, John Samperi wrote:

> At 11:01 AM 30/01/2012, you wrote:
> >add significant functionality down the ROAD
> 
> Surely you mean "down the TRACK"....... ;-)
> 
> Regards
> 
> John Samperi
> 
> ********************************************************
> Ampertronics Pty. Ltd.
> 11 Brokenwood Place Baulkham Hills, NSW 2153 AUSTRALIA
> Tel. (02) 9674-6495
> Website http://www.ampertronics.com.au
> *Electronic Design * Custom Products * Contract Assembly
> ********************************************************
> 
> 



[Non-text portions of this message have been removed]

> From: John Samperi
>
> At 11:01 AM 30/01/2012, you wrote:
> >add significant functionality down the ROAD
> 
> Surely you mean "down the TRACK"....... ;-)

Of course .... unless the project gets derailed ;-)
 
Cheers,

Chuck Hackett
"Good judgment comes from experience, experience comes from bad judgment"
7.5" gauge Union Pacific Northern (4-8-4) 844
http://www.whitetrout.net/Chuck

Hi Chuck,

> My board is designed around the ATMega32A and I am about at its memory
> limits (with optimization turned on) and I have more features to add
> (naturally).  I would like to upgrade to the largest compatible processor
> that:
> - 5v supply
> - TQFN-44 package

Would something like the RailStars RS-IO board interest you?

http://www.openlcb.org/trunk/prototypes/hardware/r-io/index.html

It's a OpenLCB development/evaluation board that has a CAN interface and is
being developed as part of the OpenLCB project.

Regards

Alex Shepherd

> From: Alex Shepherd
> ....
> Would something like the RailStars RS-IO board interest you?
> 
> http://www.openlcb.org/trunk/prototypes/hardware/r-io/index.html
> 
> It's a OpenLCB development/evaluation board that has a CAN interface and
> is being developed as part of the OpenLCB project.

Hi Alex,

Sorry for the delay, I had to upgrade my copy of Eagle from V5 -> V6 before
I could open the board ...

It looks interesting.  What is the actual/expected cost of these boards?

Some thoughts as it pertains to my application:

1) My track inputs (8) are all analog with a filtering and, since this is an
outdoor application, surge suppressor (i.e.: lightning protection ...
induced surge, not direct strike).  Likewise I have surge protection on the
incoming power.

2) You have 16 I/O lines, my board incorporates a TLC59116 (16-CHANNEL Fm+
I2C-BUS CONSTANT-CURRENT LED SINK DRIVER) to drive five 3-lamp LED signal
heads.
 
Cheers,

Chuck Hackett
"Good judgment comes from experience, experience comes from bad judgment"
7.5" gauge Union Pacific Northern (4-8-4) 844
http://www.whitetrout.net/Chuck

Hi Chuck ---

Alex let me know that you were interested in our stuff.  

The OpenLCB group is developing the Io board with Railstars as a development board that will be part of our OpenLCB / NMRAnet S-9.7 Developers and early adopters development kit, DevKit for short.  

As such, it would be useful to you for development and to try it out as a solution, but it is not meant to be an actual end-user product.  It breaks out one port as inputs, and another as outputs with built-in FETs and LEDs.  The other ports are brought out to 4 2x5 headers which can be used with ribbon cable connectors.  We are concentrating on getting these out as the DevKits, but they would likely be available separately quite soon, if their is interest.  I have included the announcement of the openlcb egroup below.  

You might also be interested in the other RailStar products, the LEDuino which has built-in CAN, and TCH Tecnology's OpenLCB compatible boards, including 32 input, 32 output and a 24/32 input/output boards.  

OPENLCB NMRANET S-9.7 DEVKIT for Developers and Early Adopters

The OpenLCB/NMRAnet DevKit is a develpment kit targeted at both OpenLCB/NMRAnet developers and users.  We want to push forward development, but also to demonstrate its use on MRR layouts.  

The present proposed contents of each DevKit is: 
(1) Three or four Io v1.0 nodes (generated pictures are in http://groups.yahoo.com/group/openlcb/photos/album/0/list);
(2) A 8 Button/LED mini-board;  
(3) One USB-CAN adapter; 
(4) Probably one USB-Serial programming cable; 
(5) Two or three CAT5 1' cables; 
(6) Assortment of connectors: two 1x10 screw-terminals, four 2x5 shrouded headers, pin-headers; 
(7) QuickStart manual.  

A more complete manual will be available on-line.  The Io nodes are Arduino compatible, and can use the Arduino IDE to develop Sketches, which can be downloaded to the nodes.  

I would like to thank our sponsors: 

-- The NMRA, through Stephen Priest for monies to buy some DevKits;
-- Railstars / Don  Goodman-Wilson for node schematic and pcb design, software/firmware and documentation; 
-- TCH Technology / Tim Hatch for USB-CAN adapter; 
-- Silicon Railway / David Harris for node schematic and pcb design, mini-board design, procurement, and seed money; 
-- John Plocher for seed money; 
-- Alex Shepherd, Bob Jacobson, John Day and others for ideas and support.   

The total cost has not been determined, but there will be a co-pay portion for the buyer, both to offset costs, and a proof of commitment ;-)   The details of how much and how the DevKIts will be distributed have not been decided as yet.  Some will be distributed directly to users, but others may be distributed through a contest or by auction.  

Finally, 
if you think you would like one of these DevKits, can you please send me an email to openlcbdevkit AT gmail DOT com with a paragraph with what you plan to do with it, and how much you would be willing to pay.  This will help determine how many people are interested and how we should proceed.  


Thanks,
David
 



--- In AVR-Chat@yahoogroups.com, "Chuck Hackett" <egroupscdh@...> wrote:

>
> > From: Alex Shepherd
> > ....
> > Would something like the RailStars RS-IO board interest you?
> > 
> > http://www.openlcb.org/trunk/prototypes/hardware/r-io/index.html
> > 
> > It's a OpenLCB development/evaluation board that has a CAN interface and
> > is being developed as part of the OpenLCB project.
> 
> Hi Alex,
> 
> Sorry for the delay, I had to upgrade my copy of Eagle from V5 -> V6 before
> I could open the board ...
> 
> It looks interesting.  What is the actual/expected cost of these boards?
> 
> Some thoughts as it pertains to my application:
> 
> 1) My track inputs (8) are all analog with a filtering and, since this is an
> outdoor application, surge suppressor (i.e.: lightning protection ...
> induced surge, not direct strike).  Likewise I have surge protection on the
> incoming power.
> 
> 2) You have 16 I/O lines, my board incorporates a TLC59116 (16-CHANNEL Fm+
> I2C-BUS CONSTANT-CURRENT LED SINK DRIVER) to drive five 3-lamp LED signal
> heads.
>  
> Cheers,
> 
> Chuck Hackett
> "Good judgment comes from experience, experience comes from bad judgment"
> 7.5" gauge Union Pacific Northern (4-8-4) 844
> http://www.whitetrout.net/Chuck
>