FTDI only sending junk « Jee Labs Talk

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FTDI only sending junk

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seblindberg

I have hooked up my brand new JeeNode to a FTDI to USB adapter from Parallax (rs232r), but all I get is this junk:
ëI[s?75%!£?E¿}¿-¿1??¿¿???¿eo¿åë(ë}=-'=;'5¿9!%%=#7?åë¿¿?##?¿-¿¿¿¿¿¥¿5¿#!75¿mw¿¯=#7=7¿#!75¿-7¿=5¿££??åë¿¿¿¿¿¿¿¿¿¿¿¿¿¿¿¯!¿5#5¿=#¿59=5¿±}±££±K±¿!¿5¿-7åë¿¿?#?¿;¿¿¿¿¿¿¥¿5¿eo¿;=#7¿¯?¿
I am guessing this is not how it is supposed to look... I am on a mac, I have tried it in a few different serial console applications, I have reinstalled the drivers without any luck and the baud rate is correct. What could it be?

Posted 08/06/2010 13:27:59
mdamen

You may have a badly flashed Jeenode. Is it a recent one? See this blog post: http://news.jeelabs.org/2010/05/28/dear-mr-murphy/

Posted 08/06/2010 13:45:36
tankslappa

57600, 8, 1, none?
Have you used this parallax adapter before on anything else?
Or as Mdamen says, you might have an escaped Murphy.

Posted 08/06/2010 13:46:50
seblindberg

I received the Jeenode yesterday. Could it be affected? Maybe I should try to upload a new firmware?
I have used the adapter to program a basic stamp chip. It has always worked for that so I figured it shouldn't be anything wrong with it or the driver.

Posted 08/06/2010 13:52:49
tankslappa

There was only a short window where a few problem chips went out. If yours was ordered or posted after 28th May it shouldn't be one of them.
I'm not familiar with that adapter, do you know if it's using TTL or RS232 levels?
Unless you have an ISP programmer you won't be able to update the bootloader. If you do it's only the fuses that need correcting.

Posted 08/06/2010 14:03:02
seblindberg

Hm, I am not sure, but there are two ICs on the adaptor which I guess speaks for TTL? Or it is something else, I don't know, but if it is using TTL levels I presume it wouldn't work?
I don't think I have a faulty chip, as the other one I ordered behave exactly the same.

Posted 08/06/2010 14:14:58
tankslappa

The Jeenode wants TTL levels. They are happy with either 3.3 or 5v levels. I use all of mine with a TTL-232R-5.0v cable I got with my 5v Barebone board from moderndevice and it's never complained. They also work on the USB BUB on both 3.3 and 5v logic levels.
You say "the other one" that you ordered, do you mean another JeeNode does the same? Did you order them both at the same time? Was it after 28th May?
I think JC emailed everyone that was or could have been affected to warn them of the mistake in the configuration. Sorry saying "faulty" was the wrong word. The chips are fine, they just have a mistake in their fuse settings, which means the baud rate ended up at an unusable rate. If you have an ISP programmer it's easy to correct.
I'm sure JC will be here in a minute to state to totally obvious that we've all missed!

Posted 08/06/2010 14:30:35
seblindberg

I ordered them in the beginning of this month, so they should both be fine then. Just in case the fuses are the problem, do you know what the correct values for them are?

Posted 08/06/2010 14:36:26
tankslappa

JC is very open/honest when he discovers a mistake so, unless this is a new one, they should be fine.
As you asked, the correct fuses are: -U efuse:w:0x05:m -U hfuse:w:0xDA:m -U lfuse:w:0xFF:m
But I don't think that will be the issue. Do you have a link to this Parallax adapter, I can't find one with two ICs.
Just a check, looking at the top of the JeeNode board, going along the FTDI connector, starting with "GND/BLACK" can you just check the connection with a meter GND/BLACK - ATmega pin 8 NC PWR - No connection to ATmega, but will connect to the P pins on the four ports TXD - ATmega Pin 2 RXD - ATmega Pin 3 RST - No connection to ATmega, but will connect to nearest leg of C1

Posted 08/06/2010 14:50:24
seblindberg

Oh, I found something about the parallax adaptor. Apparently it is using rs232 levels. Could that be the reason it is not working?

Posted 08/06/2010 14:50:30
seblindberg

I checked all the connections and they seems fine. Here is a link to the adaptor, but there is not a lot of information about it:
http://www.parallax.com/StoreSearchResults/tabid/768/txtSearch/rs232/List/0/SortField/4/ProductID/378/Default.aspx

Posted 08/06/2010 14:58:14
tankslappa

A-ha!
That would do it! True RS232 levels swing either side of 0 volts, so 5 volt RS232 would have +5 volts for on, and -5 volts for off. Values closer to zero are invalid and treated as noise. IIRC RS232 can go as high as 21 volts.
TTL uses 0 volts for off and whatever the specified TTL level is for on. So 3.3 or 5 volts.

Posted 08/06/2010 14:59:42
seblindberg

Oh well, I knew I should have ordered the USB BUB right from the start : ) Better get to that store now before it closes! Thank you very much for your help! As my first real forum experience this was not bad.

Posted 08/06/2010 15:03:24
tankslappa

Wooooo, hang on a second, we've cross posted!
I'm just looking at that adapter, and it looks okay (I'm still waiting for the big image to load, it's going very slowly!).

Posted 08/06/2010 15:05:19
seblindberg

If you are looking for that second IC it's on the other side. I found this thread at the parallax forum where they mention the adaptor in post #3:
http://forums.parallax.com/forums/default.aspx?f=5&m=420612&p=1&ord=d
"the $14 FTDI USB to RS232 adapter Parallax is selling has RS232 voltages on the signal pins -- meaning +-3 to 5 volts"
USB BUB still needed?

Posted 08/06/2010 15:09:04
tankslappa

Can you read what that chip on the USB interface says on it? It looks like an FT232RL, if so then that's exactly what the USB BUB has on it.
I wouldn't be surprised if the Parallax interface uses that to provide the USB to TTL, and then this other mystery chip which hides on the bottom to change the levels.
Probably best to order the USB BUB... Although I would probably get bored waiting and destroy the Parallax interface trying to get to the levels from the FT232RL ;-) RX - Pin 5 TX - Pin 1 DTR - Pin 2
;-)

Posted 08/06/2010 15:10:53
seblindberg

I managed to read the letters on the second IC so here is a datasheet for it: http://www.zywyn.com/files/ZT230Fds.pdf

Posted 08/06/2010 15:17:20
tankslappa

Ah, yes, that's the level converter that's ruining everything :-( I don't want to encourage vandalism on very high density pinned ICs, but is the chip on the top an FT232RL?

Posted 08/06/2010 15:25:33
seblindberg

Yes it is, but don't start suggesting I try to desolder anything now ; ) I will break it if I do!

Posted 08/06/2010 15:32:03
tankslappa

I wouldn't desolder the whole thing, just "requisition" the three pins I want ;-)
Don't worry, it's good that most people don't do the daft things that cross my mind. Otherwise everyone would have boxes of broken bits! To be honest even I might hold back on the FT232, those legs are a bit close together to try to pick out individually and bend up.
Oh well, at least we got to the bottom of it.
Anyway, welcome to the forums! They/We are a friendly bunch, and most of them know more about what they are doing than me!

Posted 08/06/2010 15:40:16
seblindberg

I get those impulses too sometimes ; ) I have learnt how to control them... Well, once again, thanks for the help!
Now I will sit down and wait for my packet to arrive.

Posted 08/06/2010 15:49:30
jcw

Sebastian, are you still getting junk at 57600 baud and your FDTI interface is in the 3..5V range?
I suspect a badly programmed ATmega. Shouldn't have happened, but perhaps one of the bad chips slipped through. Will follow up by email.

Posted 08/06/2010 16:00:37
tankslappa

JC, I think you might be innocent on this one ;-) His Parallax FDTI board has an RS232 level converter connected to the FT232RL.

Posted 08/06/2010 16:06:49
jcw

One unfortunate side-effect of the whole bad-atmega episode, is that my "baseline confidence" has dropped ... nothing serious, I'll manage just fine, but I see bad ATmega's everywhere now!
Let's hope the RS232 levels didn't damage anything. It's way out of spec for ATmega I/O pins.

Posted 08/06/2010 16:39:18
tankslappa

I wouldn't worry, I know you've managed to convince Paul Badger of Modern Device that you're some kind of non-sleeping super-human (no mean feat given his time zone), but we all secretly knew you're a normal human with super-human levels of enthusiasm - who doesn't sleep ;-)
It might be worth a warning note on the JeeNode information about non-arduino (stamp) FDTI cables, even the Parallax website is vague about the levels that plug uses, and as it only shows a picture of the top of the interface it looks for all the world like a USB BUB with a 9 pin D stuck on the end, leaving the RS232 level converter chip hidden on the underside ready to bite you.
Touch wood the ATmega will be okay, they're tough old things, but as you say, RS232 is way out of spec.

Posted 08/06/2010 17:11:07