Hi,
I have an Arduino uno board. When connected to USB I see a new communications port in Windows/Device Manager. From blink example code, if I click upload or burn bootloader from menu, I notice some RX/TX led activity. Then it stops, I get an error in Windows as "avrdude: stk500_getsync(): not in sync: resp=0x00" from Arduino IDE. I get this when ever I try burning boot loader or user code (sketch).
I feel my USB cable and connection must be OK since I get power to the Arduino uno board and I get bi-directional communications, as I would not see a COM port in Windows if USB traffic was not working in both directions. Is it possible I've swapped D- with D+, I doubt I'd get the communications port in Windows as the handshake to transfer the device descriptor requires bidirectional comms. I mention this because I have had to solder a cable directly to the board because of the physical connector size is to large for my project box.
I have an old STK500, I take out the 328P DIL device, setup it in AVR Studio, read fuses:
BOOTSZ = 256W_1F00
BOOTRST = [ ]
RSTDISBL = [ ]
DWEN = [ ]
SPIEN = [X]
WDTON = [ ]
EESAVE = [ ]
BODLEVEL = 1V8
CKDIV8 = [ ]
CKOUT = [ ]
SUT_CKSEL = EXTXOSC_8MHZ_XX_16KCK_14CK_65MS
EXTENDED = 0xFD (valid)
HIGH = 0xDE (valid)
LOW = 0xFF (valid)
LB = NO_LOCK
BLB0 = NO_LOCK
BLB1 = LPM_SPM_DISABLE
LOCKBIT = 0xCF (valid)
I am not sure if the bootloader is present anymore as this board used to have the blink example working before I attempted to burn bootloader and I only attempted this because normal uploads would not work and finished with the same error as I presented above. I will try and verify it in my STK500 but I need to know a bit more about the "optiboot_atmega328.hex" file.
1). Are my fuse settings correct for the optiboot to function, it looks like a small bootloader section of 256words. Assumed at start of device?
2). Is the boot loader simply written to start of flash at 0h. I assumed it would be at the end of the chip flash but...
3). Is optiboot_atmega328.hex the correct file for Arduino uno? I got it from the board config file, but there is another interesting hex for my device "optiboot_atmega328-Mini.hex"?
I've had odd behaviour where code in the 328P device flashes the on-board L led but not to the 1S intervals as expected but two fast flashes, almost like it was repeatedly rebooting or perhaps has watchdog timeouts?
Hope any of this makes sense,
Cheers,
giggler