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The Bobuino does support onboard FTDI, via the MIKROE-483 module. I chose not to have to solder that part on following difficulties getting FT232R chips soldered.
The MIKROE-483 at $10.95 combines the $4.50 FTDI chip, the USB connector, and several other parts and seemed like a great tradeoff for reliably adding a USB/Serial interface to a card for those without top-notch soldering skills.  And if your embedded project didn't need USB connectivity, then headers for offboard programming could be used.  My projects since fall 2010 have not needed USB when installed, so it works out well to have USB for debugging, and then just disconnect it for embedding.  Helps in keeping project costs down too.
http://www.mouser.com/ds/2/272/usb_uart_manual_v100-32094.pdf
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Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

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Both methods have their merits, I have other minified projects which do not include usb-to-serial. For this project which is intended as a replacement for my prototyping arduino's not necessarily as a project itself.

those without top notch soldering skills? Personally I'd phrase it more like "those without proper smd soldering tools". Maybe a pro can drag solder a 100pin qfp (I can't) but a novice can easily solder a FT232RL with a hot air rework station ($50 on ebay) or a $20 target hot plate.
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Both methods have their merits, I have other minified projects which do not include usb-to-serial. For this project which is intended as a replacement for my prototyping arduino's not necessarily as a project itself.

those without top notch soldering skills? Personally I'd phrase it more like "those without proper smd soldering tools". Maybe a pro can drag solder a 100pin qfp (I can't) but a novice can easily solder a FT232RL
with a hot air rework station ($50 on ebay) or a $20 target hot plate.

I've found that with USB TTL serial 'cable adapters' so cheap on E-bay it just doesn't make sense to mount a on-board FTDI chip. Just mount a female header to accept the adapter and with the money saved I can buy a spare ATmega1284P chip!

I've several of these and even found them easy to mod to bring the DTR signal out for allowing the IDE auto-reset to function.

http://www.ebay.com/itm/USB-2-0-to-UART-TTL-6PIN-Module-Serial-Converter-CP2102-/120802350060?pt=LH_DefaultDomain_0&hash=item1c206193ec

Lefty
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I've found that with USB TTL serial 'cable adapters' so cheap on E-bay it just doesn't make sense to mount a on-board FTDI chip. Just mount a female header to accept the adapter and with the money saved I can buy a spare ATmega1284P chip!
"male" header?

By leaving out the FTDI chip, you also get a board that draws less quiescent power, and can
be used in low-power apps more easy. Plus you don't need all the parts in the power switchover
cktry between USB and power jack.
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I've found that with USB TTL serial 'cable adapters' so cheap on E-bay it just doesn't make sense to mount a on-board FTDI chip. Just mount a female header to accept the adapter and with the money saved I can buy a spare ATmega1284P chip!
"male" header?

??? back at you.  smiley-wink The adapter I linked shows it has male pins needing to plug into something that accepts male pins, so a 6 pin female header strip maybe with right angle solder tails for a lower board profile? Marriage equality does not apply to .1" header connections.  smiley-grin 

By leaving out the FTDI chip, you also get a board that draws less quiescent power, and can
be used in low-power apps more easy. Plus you don't need all the parts in the power switchover
cktry between USB and power jack.
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I've found that with USB TTL serial 'cable adapters' so cheap on E-bay it just doesn't make sense to mount a on-board FTDI chip. Just mount a female header to accept the adapter and with the money saved I can buy a spare ATmega1284P chip!
"male" header?

??? back at you.  smiley-wink The adapter I linked shows it has male pins needing to plug into something that accepts male pins, so a 6 pin female header strip maybe with right angle solder tails for a lower board profile? Marriage equality does not apply to .1" header connections.  smiley-grin  

By leaving out the FTDI chip, you also get a board that draws less quiescent power, and can
be used in low-power apps more easy. Plus you don't need all the parts in the power switchover
cktry between USB and power jack.

hahahahaha

Guys your missing the point here, I totally agree with what your saying, but all of those things have their place among minified projects. This is supposed to be an alternative to using an actual Arduino, all the same luxaries. Do you really care how much power it's drawing when your sitting at your computer with it plugged in while prototyping some amazing new project? Probably not, not until you actually go to implement it at which point your likely not going to use your prototyping Arduino.

This is not meant to be a cheaper, or more power efficient model, there are tons of those out there already. I wanted for ME an Arduino with all the same features as a regular arduino in the same size package and thus came the Mega Junior, 1284.
« Last Edit: April 02, 2013, 05:20:29 pm by jbaum81 » Logged

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1st Mega Junior, 1284 was just sold to someone in the community and will hopefully ship tomorrow smiley.

The boards for the Mega Junior, 1284 SMD and the Mega Junior, 1284 BB were just shipped. Hopefully next week I'll have some spares to sell and designs up.

I'll be working tonight to try to get the bootloaders posted.

@Crossroads, did you not want me to include a bootloader for your Bobuino's? I had planned a 16 and 20mhz bootloader using your pinlayout.
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I am getting a little worried at the number of copies of Optiboot for 1284 that are out there.  (All with the same version number?  But not necessarily the same code?)   It's bad enough that the Optiboot repository and the Arduino repository are modified independently (and it's pretty tough to get patches from Optiboot into Arduino, just due to momentum and manufacturing issues.)  But now there are three or four copies of the 1284 optiboot out there...  (Maniacbug, jbaum, crossroads, goldilocks)
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I am getting a little worried at the number of copies of Optiboot for 1284 that are out there.  (All with the same version number?  But not necessarily the same code?)   It's bad enough that the Optiboot repository and the Arduino repository are modified independently (and it's pretty tough to get patches from Optiboot into Arduino, just due to momentum and manufacturing issues.)  But now there are three or four copies of the 1284 optiboot out there...  (Maniacbug, jbaum, crossroads, goldilocks)


I can see your concern. However, no modification is being done to optiboot itself, only extra bootloaders and custom pin configs being added. In my case you will be able to download optiboot and download my fork and they will be identical with the exception of the extra options I add. You will still see all the [optiboot] devices which will contain all the same settings and bootloaders as the original. This is tracked on google code so you will easily be able to see which files are modified.

Since arduino has not fully integrated Optiboot, included 1284, and allowed for quick easy pin configurations I really see no other way.

Unless you have the know how and download optiboot and compile your own. Which I did mention earlier I thought that a good tutorial on how to do so may not be a bad idea.
« Last Edit: April 02, 2013, 06:25:04 pm by jbaum81 » Logged

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download optiboot and compile your own. Which I did mention earlier I thought that a good tutorial on how to do so may not be a bad idea.
The wiki at http://code.google.com/p/optiboot/wiki/ has had some work done recently...
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download optiboot and compile your own. Which I did mention earlier I thought that a good tutorial on how to do so may not be a bad idea.
The wiki at http://code.google.com/p/optiboot/wiki/ has had some work done recently...


Still somewhat vague for 1284 and other non mainstream AVR's. No matter what your still going to have to do some modifications on the boards file and possibly a pins file.
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Yep.
How are  you dealing with the differences in platform support between different Arduino IDE versions?
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I am getting a little worried at the number of copies of Optiboot for 1284 that are out there.  (All with the same version number?  But not necessarily the same code?)   It's bad enough that the Optiboot repository and the Arduino repository are modified independently (and it's pretty tough to get patches from Optiboot into Arduino, just due to momentum and manufacturing issues.)  But now there are three or four copies of the 1284 optiboot out there...  (Maniacbug, jbaum, crossroads, goldilocks)
Maybe you could contact maniacbug and get him to update his library, change the fuses,
look at the open issues posted to the github page. I tried, but he ignored me. I'm just
a mere mortal.

Also, as I understand it, maniacbug optiboot is the same for all of the variants in his
library, and only the pins_arduino.h and the boards.txt files need to be customized for
the different variants. So, there's probably no reason to have more than 1 extant optiboot
bootloader. If jbaum and goldilocks have changed it, it may not have been necessary.
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I've found that with USB TTL serial 'cable adapters' so cheap on E-bay it just doesn't make sense to mount a on-board FTDI chip. Just mount a female header to accept the adapter and with the money saved I can buy a spare ATmega1284P chip!
"male" header?

??? back at you.  smiley-wink The adapter I linked shows it has male pins needing to plug into something that accepts male pins, so a 6 pin female header strip maybe with right angle solder tails for a lower board profile? Marriage equality does not apply to .1" header connections.  smiley-grin 

By leaving out the FTDI chip, you also get a board that draws less quiescent power, and can
be used in low-power apps more easy. Plus you don't need all the parts in the power switchover
cktry between USB and power jack.

Darn, ebay strikes again. [are you still buying that stuff? ;-)]. I've never seen an FTDI cable
with male headers, but this isn't FTDI either.
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I've found that with USB TTL serial 'cable adapters' so cheap on E-bay it just doesn't make sense to mount a on-board FTDI chip. Just mount a female header to accept the adapter and with the money saved I can buy a spare ATmega1284P chip!
"male" header?

??? back at you.  smiley-wink The adapter I linked shows it has male pins needing to plug into something that accepts male pins, so a 6 pin female header strip maybe with right angle solder tails for a lower board profile? Marriage equality does not apply to .1" header connections.  smiley-grin 

By leaving out the FTDI chip, you also get a board that draws less quiescent power, and can
be used in low-power apps more easy. Plus you don't need all the parts in the power switchover
cktry between USB and power jack.

Darn, ebay strikes again. [are you still buying that stuff? ;-)]. I've never seen an FTDI cable
with male headers, but this isn't FTDI either.

Never stopped E-bay scrounging, it's a disease. Not FTDI based but rather CP2102 based, but drivers are freely available and the arduino IDE doesn't care, it just wants to talk to comm ports.

Lefty
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