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Hi
I use the Nano RS232 Programmer Interface of the Data Sheet.
(2x 10k and a Diode to TX )
Starting “Program”, and the Studio2 shows:
“A BasicATOM NANO processor must be connected to program”

My Com1 is O.K. …Atom and AtomPro is programming.
Atom Nano 18 is activated in studio2.
I tried different Reset Hold Time….but no successes.
I test the Diode 600mV, test the two resistor; 10k each.
What else can I try ??
Heinz

Is your serial connection between the nano going right to the PC or are you using a RS=232 to TTL converter?

The Nano uses TTL signals for programming. so you'll need a max232 or something similar like http://www.pololu.com/catalog/product/126

I didn't know that either at first,

Edit: actually the link i posted doesn't offer much info.


If you want to use a serial com port on your PC, you'll need an RS-232 to TTL converter.

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Hi Fallentine
The USB Interface is one solution.
In the Atom Nano Data Sheet there is a description of an other solution:
Nano RS232 Programmer Interface:
Reducing level with a Diode and resistor to the” Nano level” may be about 5V
….I believe….
Heinz

The data sheet says that the resistors and diode are used with TTL levels, but doesn't mention the MAX232 level-translator IC directly. And you have to invert the levels when talking to a PC, so just dropping the +/-12 to TTL levels isn't enough. The -9 to -12 becomes +5, and the +9 to +12 becomes 0V, and vice versa going the other way. The USB programmer adapter you mention takes the PC's TTL level USB signals and produces the proper TTL signals both ways. For just $15 it's a slick trick. After programming is done, it works as a serial port! Just use
SEROUT s_out, etc
or
SERIN s_in, etc.
to make this work for bitbang serial (only).
Take care.

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kenjj
http://blog.basicmicro.com/
http://kjennejohn.wordpress.com/

What Kenjj said.

The Nano RS232 converter, doesn't just convert USB to serial, but also from Serial to TTL.
Now, if you already have a Serial to TTL converter, using the resistor/diode method will work fine. But the programming signals are infact TTL
0v/+5v
Where RS232 is normally -12v/0v/+12v.

I still believe it's a problem in the manual. It should state clearly in bold/caps, multiple times throughout the programming sections, that the programming signals are indeed TTL.
If it's just me that got mixed up by that, that's one thing. But now 2 people? Who knows how many others out there got mixed up on this too.


RS-232 is the PC Com ports output. NOT TTL. After my mishap with this problem, i looked up RS232, and they all refer to ±voltages. Not the 0v/+v of TTL. http://www.ideamarketers.com/?RS232&articleid=771738


As i just covered, TTL is not a Typical RS232 circuit.
And standard USB to Serial adapters put out RS232 ±12v, not TTL.
The Nano USB Programmer is an exception. It's one of the few USB Serial converters that do indeed output with TTL.

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Just wondering if anyone has tried the Parallax Prop Plug: http://www.parallax.com/Store/Microcont ... fault.aspx

For this. For the fun of it I did purchase a Nano 40 and a Nano 18 and a Nano Dev Board. I have not done much with the Nanos yet other than I did download the updated test program and did verify that it would load on the Nano40.

For the Nano18 I thought I would try a breadboard for it. Would be easy if the Prop plug works, otherwise I do have a ADM232.. Chip I used awhile ago with a AVR atmega32 chip, that I could probably wire up to do the conversion...

Kurt

Nano18 on a breadboard? Hmmm... Sounds familiar, somehow...
Oh! Yeah! Go to my signature below and click on the kenscorner link. You may find something useful to study!
As for the $15 USB-Serial programming adapter, it eliminates so much possible trouble through miswiring, just GET IT!

I have half a mind (always) to produce an app note on the use of serial, soft and hard, with the Atom parts.
Later.

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kenjj
http://blog.basicmicro.com/
http://kjennejohn.wordpress.com/

Hi Ken,

Yep I looked over your blog before (Note: your signature does not show it as Ken's corner )

Yes I could use the $15 converter plus minimum of $14.29 to ship it. Or of course I could simply plug it into the Nano Dev Board, but that is no fun

But as a third choice I was wondering if anyone tried the Parallax Prop Plug. It takes the usb and has 4 pins that come out that it say is compatible with +5 and +3.3v devices. The signals are:
RX, TX, not RST and Ground.

Schematic of the prop plug are in the PDF file you can download from the link I put in the previous post.
The RX/TX go directly to the FTDI chip with a 150 ohm resistor.
The RST line goes to DTR through capacitor plus an NPN transistor

Right now I am just playing around, spending vast majority of my time with Pros... Just thought it might be fun to experiment to see if I could use a real cheap add to add functionality to my Pros. Wonder how hard it would be to make the Nano work well as a I2c Client... Maybe have it monitor something like RC receiver and allow the main processor simply do an I2CRead when it wants the data... But that is more a question for a different thread...

Kurt

Silly me. Didn't bother to read my own signature after submitting the post. That's why I don't make the big bucks.
Thanks for the tip on the clip/plug. I have some designs in mind that need a QnD way to add an as-needed second serial port. I liked it so much I ordered one. Seeing as how shipping was 57 cents using USPS 1st class mail, why would I hesitate?
Parallax's minimum UPS Ground was $9.70.
BMicro is $14+, and no less expensive choices. I'd LOVE to order a small $10 part from them, but the extra $14 stops me. Guess I'll wait till I place a large order that "absorbs" the shipping costs.
Later!

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kenjj
http://blog.basicmicro.com/
http://kjennejohn.wordpress.com/

I'd be buying more stuff too if it wasn't for the shipping.
It's hard to justify paying more for shipping than what you pay for your order.
I don't pay $14 for shipping unless it's justified by weight. Like a new computer LCD or Case.
If Basic micro starts offering US Postal First class and Priority, it would help the costumers and help their own sales.
Any of bmicro products can fit into a $6 priority mail box. ($5 plus delivery confirmation, which doubles as tracking.)
You can fit one of every Bmicro product into a $10 priority mail box.
So never in a million years will i pay $14 for shipping on a $15 nano programmer.


Now, back on topic.
HSchwenk
Did you solve your problem? Do you need further help on this?

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Hi
I believed that an RS232- is not a TTL circuit.
I understood the Data sheet:
“A typical RS232 circuit or USB to Serial….”
in the way that I can joy one of the two circuits, because of the “or”
and did not think about how the Nano could manage the +-10V.
....An explaining or warning would have been helpful….
……….
Inpatient to wait for shipping of an converter, I put a Max232 and 5 cups inside a com-plug, and the Nano is to program now.

Thanks for all the approaches Heinz

An RS-232 circuit is a MAX232(or equivilent) chip along with associated parts with a DB-9 connector. The data sheets shows how to wire up a RS-232 connector to the a Nano processor. Sorry if that confused you. If you attached the RS-232 pins directly to a Nano you probably fried it(though I did the same thing today and it didn't kill the chip I was working with so I'd double check it before anything else).

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Basic Micro - Robotic Technology Evolved

RS-232 refers to the protocol or "standard" the Com port uses. DB-9 is just the connector it uses, RS-232 is the protocol which utilizes the +/- 12v voltages.
Max232 is just an RS232 converter, it's not a "rs-232 circuit."
RS-232 and DB-9 are so well associated with eachother, that the DB-9 port, can actually be called a RS-232 port.
Simply googling (rs-232 port) will give you a butt load of DB9/ PC com port related information. But little if nothing related to TTL.
It might just be a misunderstanding, or a the usage of the terms change over time and get mixed up.
From my understanding, RS-232, always referred to the com port level signals of a PC.

So when the datasheet shows how to connect up RS-232, i assumed it meant directly to the RS-232 port. And i'm not the only one to make that assumption.
The assumption stems from the lack of clarification. Unless it says it needs an RS-232 to TTL converter, we are only left open to guess based off the information provided, which says to use the RS-232 lines, IE directly from the PC's com port.
So RS-232 circuit does not quite count as RS-232 to TTL converter.

And you're right, using it directly doesn't seem to have any long lasting ill effects. I used standard serial at first too, and because the studio didn't detect the atom, it didn't send any additional signals so the nano remained, to my knowledge, undamaged.
It seems to be working fine at least.

So, 5-10 minutes to amend the datasheet and any manuals, and we shouldn't see this problem again.
I'd do it myself if i could. Except i'd probably get to wordy and extend the manual 5 pages.

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The electrical characteristics including the min and max voltages for I/Os is listed in the datasheets. But I will ask that the data sheets be changed to explicitly say, you need a RS-232 level converter circuit.

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Tech Support
Basic Micro - Robotic Technology Evolved

I'll do a blog post on this sometime soon i hope. Maybe i'll see about getting a usb nano programmer to use in various nano based blog post.
Programming pins don't count as I/O lines in the manual. And before you nip at my noes on that, the BAPro 28's manual, under electrical characteristics list that the signals are 0v/5v, TTL.
The BAPro 28's manual also says the S_in and S_out pins connect to the RS-232 TX and RS-232 RX lines, respectively.

I'm really happy this is getting fixed, i'm also really happy all our nanos didn't receive any damage.
In a semi unrelated note, you know how i often refer to the basic atom pro, as the BAPro.
Well I just referred to the nano as a Bananos.
I'll have to do a comic on that some day.

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