Hi, Sorry for my bad English.
My products, using AT90USB162, is HID mouse, keyboard, and CDC composite device.
The state of produce, the device works correctly.
But, 1~3 months later, 10% of products don't work.
The main source is AVR272.
The circuit is attached.
Fuse setting is
- BOD 4.3V, 16MHZ Crystal.
- SPIEN, BOOTZ $1800
- SUT_CKSEL 16CK + 65ms
- Use Bootloader and FLIP 3.4.2
The case of incorrect working is
- The state of inserting to USB port, jumping to
bootloader is 10%
- No enumeration of one device is 30%
- No enumeration of all device is 50%.
When C1 AND C2 use 4.7uF, or 10uF, or 20uF, or not use
of Cap, the result is same.
When use below code, 10% is that the device goes to bootloader.
TIMSK1 = 0;
asm("JMP 0X00000000"); // 10% is going to bootloader
When rewrite firmware with ISP, the case of correct working is 50%.
Please help me!!