Datasheet

263
7799D–AVR–11/10
ATmega8U2/16U2/32U2
Note: a = address high bits, b = address low bits, c = address extended bits, H = 0 - Low byte, 1 - High Byte, o = data out, i = data in,
x = don’t care
25.9.2 Serial Programming Characteristics
For characteristics of the Serial Programming module see “SPI Timing Characteristics” on page
269.
Read Extended Fuse Bits
0101 0000 0000 1000 xxxx xxxx oooo oooo Read Extended Fuse bits. “0” = pro-
grammed, “1” = unprogrammed. See
Table 25-3 on page 247 for details.
Read Calibration Byte 0011 1000 000x xxxx 0000 0000 oooo oooo Read Calibration Byte
Poll RDY/
BSY
1111 0000 0000 0000 xxxx xxxx xxxx xxxo If o = “1”, a programming operation is
still busy. Wait until this bit returns to
“0” before applying another command.
Table 25-16. Serial Programming Instruction Set (Continued)
Instruction
Instruction Format
OperationByte 1 Byte 2 Byte 3 Byte4