system
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Hi all,
Used Nick Gammon's chip programmer with the UNO-R3 as ISP to burn bootloader on Pro Mini (with ATmega 328P); worked fine result ok.
But can't upload sketch to Pro Mini through USB2SERIAL (worked before burning bootloader and still works with other Pro Mini) and I get the comment:
avrdude: stk500_getsync(): not in sync: resp=0x00
Can anyone tell me what this means? What can I do to make it work again?
The basic issue is that there is no automatic reset of the Mini Pro when the serial line becomes active.
Here is the process that I use:
- Start the compile/download cycle
- At some point the 'Rx' LED on the MiniPro will flash.
- Press the reset button when this happens.
- The bootloader will take over on reset and allow the download to be executed.
It can be a bit tricky, but like most of these things the timing will comm with practice 
An alternative is to modify the Pro Mini woith a capacitor (from memory) that reset the serial line. You can search for this using google.