Alternative to 16U2

I want to build my Arduino UNO clone. I wonder if I can use this chip ( AT89C51CC02CA-TISUM MICROCHIP (ATMEL) - IC: microcontroller 8051 | Flash: 16kx8bit; SO28; AT89; AT89C51CC02CTIS | TME - Electronic components ) instead of ATMega 16U2 for USB interface, because I don´t have much practice with soldering small components like 16U2. And for the last if I can program that chip with classic 16U2 firmware via original UNO rev.3 . Thanks for soon reply.

How can you program a chip with the firmware of another chip, please explain.

The Arduino Nano uses the FT232
http://arduino.cc/en/Main/arduinoBoardNano
The Arduino Pro Mini doesn't have a USB connection at all.

Do you want to build a standalone or a clone ?

I want to build my Arduino UNO clone.

No!

You want to build http://arduino.cc/en/Main/arduinoBoardDuemilanove

mrburnette:

I want to build my Arduino UNO clone.

No!

You want to build http://arduino.cc/en/Main/arduinoBoardDuemilanove

I second this, you better build a Duelmilanove with FTDI.
Or easier, an Arduino Severino.

I'm slow. Can someone tell me why he should build either of those (as opposed to a garden variety UNO) ?

raschemmel:
...Can someone tell me why he should build either of those (as opposed to a garden variety UNO) ?

My thinking is that the FTDI can be purchased as a module on breakout (or inside the USB shell on a nice long cable). Everything else is a garden UNO and with Optiboot bootloader and the reset cap, it will work like an UNO... Just no need to deasl with 16U2 or 32U4.

Ray

Do I have to read all the spec for the Duelmilanove to understand why you guys recommended that one ? What's special about that?

raschemmel:
Do I have to read all the spec for the Duelmilanove to understand why you guys recommended that one ? What's special about that?

See reply #5, for my thinking.

I use a Sparkfun FTDI BASIC for my 3.3V Pro-Mini, 5V Pro-Mini and breadboarded ATmega328 chips. It works great. no problems.

mrburnette:
or inside the USB shell on a nice long cable

NOW we are cooking with gas. i am always amazed at the number of people who still like to put that usb/tll converter on every board. talk about redundancy.

I use a Sparkfun FTDI BASIC for my 3.3V Pro-Mini, 5V Pro-Mini and breadboarded ATmega328 chips. It works great. no problems.

Nice. Have one... rarely used, however, but always works.

i am always amazed at the number of people who still like to put that usb/tll converter on every board. talk about redundancy.

Yes! And so cheap in today's marketplace... if one takes a few minutes to look for a bargain.

Lots of options. I just did not want a newbie to run out and buy a surface mount 16U2 or 32U4 and a 328P-PU just to copy a UNO design in detail. Deviating down the forerunners to UNO before the 16U2 is a better approach, IMO.

Ray

personally, unless you are fixated on "shields", i think pro-mini is the best target for those starting out. not only 1/10th the cost of the huge boards like duemanilove or uno but actually more signal pins available. very friendly and standardized pin arrangement compared to those of the big brothers. much easier to build from scratch too.

admittedly nice being able to plug in a new chip on those big socketed boards but pro-mini is so cheap at $2-$3 shipped dollars its almost not worth it.

john1993:
...
admittedly nice being able to plug in a new chip on those big socketed boards but pro-mini is so cheap at $2-$3 shipped dollars its almost not worth it.

It's a good point but the sub-$3 range is for the China variety of the clone. These clones often have varying pinouts, especially around the Vcc/Gnd area of the board. So caution needs to be utilized and the realization that one board ordered today may differ from one board ordered two months ago.

The other issue, which should be considered, is the need to have a soldering iron and decent skills in using said iron. Even if you just need to solder the headers for breadboard use. Soldering and unsoldering wires to the little boards will eventually cause copper foil lift at which time the board.

It is a cheap and viable solution, but not one that I would recommend for the "My First Arduino" award. Buying a UNO has many benefits for newbies. For EE's, HAM's, or ET's with hardware buildout experience... yea, go for the cheap... they generally work. My last shipment of 5 Pro Micros and 2 dead units... one was revived with reflashing the bootloader for the 32U4 but one is eternally dead. The previous 10 Pro Micros were 100%. 2 duds out of 15 may be an unacceptable rate of failure and most newbies will be unable to flash the 32U4: something to think about.

Ray

mrburnette:
It's a good point but the sub-$3 range is for the China variety of the clone. These clones often have varying pinouts, especially around the Vcc/Gnd area of the board. So caution needs to be utilized and the realization that one board ordered today may differ from one board ordered two months ago.

Plus the FTDI connector is completely randomly oriented on them. You have to look where Vcc is every single time you connect one.

mrburnette:
The other issue, which should be considered, is the need to have a soldering iron and decent skills in using said iron. Even if you just need to solder the headers for breadboard use. Soldering and unsoldering wires to the little boards will eventually cause copper foil lift at which time the board.

Yep. The first thing you need to do when you open one is get out the soldering iron. Not exactly beginner-friendly.

mrburnette:
It is a cheap and viable solution, but not one that I would recommend for the "My First Arduino" award.

Agree. Develop with the Uno, save the Pro Minis for building into the final gadgets.

mrburnette:
My last shipment of 5 Pro Micros and 2 dead units... one was revived with reflashing the bootloader for the 32U4 but one is eternally dead. The previous 10 Pro Micros were 100%. 2 duds out of 15 may be an unacceptable rate of failure and most newbies will be unable to flash the 32U4: something to think about.

I've gone through 30-40 of them and haven't had a problem yet (touch wood). Even so, I don't see that as a big deal. What's a few dead ones when they're $3 each with free shipping? Just make sure you always order plenty of spares so you're never in a hole waiting for slow shipments to arrive.

I usually buy the ones with ISP connector and flash them with optiboot as soon as I get them so the bootloader gets overwritten anyway.

of course we are all entitled to our opinions and mine is that pro is excellent for beginners. i say this after providing 200 of the cheapies to several lab classes of engineering students. they are available with pins pre-installed but i thought it better to introduce some basic solder skills. my method involves mounting pins across the top of the pad instead of through the hole and only two out of hundreds failed to boot. and no lifted pads. the headers have even been removed on a few occasions w/o that happening.

as far as random pinout the actual "pro-mini" pads on the sides are consistent on all units ive purchased from many different asian sources, both ebay and aliexpress. only the enhanced signals like extra adc channels and serial varied and this was for improvement over the original sparkfun design. the current design also supports jumper selectable 3.3v or 5v operation which is another major improvement.

so considering you can buy a dozen of these for the cost of a "real" arduino i highly recommend for beginners. if the official pro-mini, which was not designed by arduino btw, would compete in terms of cost and features i would recommend it.

Well there are two different questions going on here. The OP stated he wanted to build his own arduino board and a second topic of quality/usefulness of inexpensive Asian nano/micro/uno boards.

My thoughts are unless one really just wants the experience/educational value of building an arduino from components, it's just not a cost or time effective effort. Better to put the time and effort into a shield or wired board that does something useful or interesting. Even for just bread-boarding it's hard to beat a < $10 Nano board that just plugs into a breadboad and has the usb connector ready to go and can even have it's bootloader updated to the latest optiboot version. And for insertion into a PCB it's hard to beat the $3 pro-minis. I've bought a few of both and seen no problem in quality or performance.

However that doesn't change my recommendation that a beginner should start off buying one 'real' arduino Uno board, just call it the 'entry cost' to our great community. :wink:

retrolefty:
Well there are two different questions going on here. The OP stated he wanted to build his own arduino board and a second topic of quality/usefulness of inexpensive Asian nano/micro/uno boards.

If anybody wants to put an AVR chip in a breadboard and program it just to see how it's done then they probably should do it.

For building gadgets? The Pro Mini is unbeatable IMHO.

Unless you need USB connectivity, obviously ... or you can use a Tiny85 if it needs to be really tiny. Apart from that, they're unbeatable.

retrolefty:
However that doesn't change my recommendation that a beginner should start off buying one 'real' arduino Uno board, just call it the 'entry cost' to our great community. :wink:

:slight_smile: