Three weeks after ordering, it arrived by registered mail, exactly as depicted. This one is different from the other Pro Mini boards I've seen in a couple ways. First is that it uses a QFN (quad flat no-lead) package ATmega328P instead of the slightly larger and more common QFP (quad flat pack). The other difference is that it uses a crystal oscillator instead of a smaller resonator. Crystal oscillators are more accurate, which is useful if you need accurate time keeping. The board came with no documentation, so I assumed it would work like a standard Arduino Pro Mini.
After opening the package I just soldered on the 90 degree header for the serial connections, then connected it into a PL2303HX USB-TTL adapter. The red power LED came on, and the blue LED started flashing - indicating the pre-loaded blink sketch was running. The blue LED is quite bright, even though it uses a 750 Ohm current-limiting resistor. I selected Pro Mini 5v @ 16Mhz from the Arduino IDE, pressed reset, and tried uploading a test sketch. Avrdude timed out, so I tried again. There was only one quick blink of the LED - indicating a short timeout for the bootloader. In case the board was using optiboot @ 115,200kbps, I changed the upload speed in the boards.txt file, and tried a few more times but still no luck.
I decided to flash a new bootloader so I'd have a known configuration. I chose the Uno from the boards menu because it's configuration uses the optiboot bootloader @ 115,200kbps. I connected my USBasp, selected USBasp from the programmer menu, then selected "burn bootloader".
After 10-15 seconds it was finished. I loaded my test sketch, clicked the upload button, pressed reset on the Pro Mini after the "Running AVRDUDE..." message appeared, and the "Done uploading" message quickly appeared. My sketch was loaded and running. Considering the $3.65 I paid for it, I think the Baite Pro Mini is a good buy.
2014/09/22 update:
The Pro Mini boards are now selling for $2.50 or less on Aliexpress, so I picked up another one. This time I checked the fuse settings with avrdude:avrdude.exe: safemode: Fuses OK (E:05, H:DA, L:FF)
The bootsz fuse is 01, which is 2Kbyte (1Kword), which confirms they do not come with optiboot flashed (which is only 512 bytes).
Thanks for the review. It is helpful.
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