Cheap Serial Interface

[celem]

I just recently purchased, on eBay, a couple of inexpensive serial interfaces that work well and cost me $2.93 each, including postage. They are designed for 3.3V logic but they use a CP2102 IC that is 5-Volt tolerant so they also work in 3.3-Volt or 5-Volt circuits. An irritation is that the Tx and Rx lines are labeled backwards on the silk screen labels to accepted practice. To order one just search for "USB 2.0 to UART TTL 6PIN Module Serial Converter CP2102" on eBay. There are several versions on eBay. The ones that I purchased are made by http://www.betemcu.cn and the logo on the board looks like "BA\TE". See attached photo. They have a full-size USB port on one end and pins on the other. You'll probably need a USB extender cable to use it (male/female) - at least I needed one.

[johnwasser]

The ones that I purchased are made by http://www.betemcu.cn and the logo on the board looks like "BA\TE".

The same folks who made the "USBasp" programmer I bought.  $9.80 including shipping from China.

[celem]

I also have their USBasp - works great! I have only used it for programming ATtiny85 but it has been flawless - and dirt cheap. The logo is not present on my USBasp. Instead they have their website www.betemcu.cn and some Chinese characters.

[rifqi]

buy from www.betemcu.cn?
how to buy? or can i get the email for contact the admin of that site?
i want to buy too

[celem]

Rifqi - re-read my original post. I said "To order one just search for "USB 2.0 to UART TTL 6PIN Module Serial Converter CP2102" on eBay."

I said that they are made by www.betemcu.cn but did not say to buy them there.

Also - be aware that these boards do not use the standard FTDI pinout. Therefore, they are used to communicate with an Arduino but do not have the Automatic (Software) Reset used for sketch loading. Some people modify this board to provide the Automatic (Software) Reset, but you need to be somewhat hardware savvy to do this modification unless you purchase one of the CP2102 board versions that have the DTR brought out to an edge pin. Otherwise, more daunting surface mounted pin surgery is required. The easiest thing to do is to simply use this el-cheapo board for communications, not programming.