ATtiny25/45/85 Auto

Table 22-10. Serial Programming Instruction Set

					Instruction Format
	Instruction			Byte 1	Byte 2	Byte 3	Byte4	Operation
				0101	0000	xxxx	oooo	Read Fuse bits. “0” =
	Read Fuse bits			0000	0000	xxxx	oooo	programmed, “1” =
								unprogrammed. See Table
								22-5 on page 141 for details.
				0101	0000	xxxx	oooo	Read Fuse High bits. “0” =
	Read Fuse High bits			1000	1000	xxxx	oooo	pro-grammed, “1” =
								unprogrammed. See Table
								22-4 on page 141 for details.
				0101	0000	xxxx	oooo	Read Extended Fuse bits. “0”
	Read Extended Fuse			0000	1000	xxxx	oooo	= pro-grammed, “1” =
	Bits							unprogrammed. See Table
								22-3 on page 140 for details.
	Read Calibration Byte			0011	000x	0000	oooo	Read Calibration Byte
				1000	xxxx	0000	oooo
				1111	0000	xxxx	xxxx	If o = “1”, a programming
				0000	0000	xxxx	xxxo	operation is still busy. Wait
	Poll RDY/BSY							until this bit returns to “0”
								before applying another
								command.

Note: a = address high bits, b = address low bits, H = 0 - Low byte, 1 - High Byte, o = data out, i = data in, x = don’t care

22.6.2Serial Programming Characteristics

Figure 22-3. Serial Programming Timing

MOSI

tOVSH

tSHOX

tSLSH

SCK

tSHSL

MISO

tSLIV

Table 22-11. Serial Programming Characteristics, TA = -40°C to 125°C, VCC = 2.7 - 5.5V

(Unless Otherwise Noted)

Symbol

Parameter

Min

Typ

Max

Units

1/tCLCL

Oscillator Frequency (ATtiny25/45/85V)

0

4

MHz

tCLCL

Oscillator Period (ATtiny25/45/85V)

250

ns

1/tCLCL

Oscillator Frequency (ATtiny25/45/85L, VCC = 2.7 -

0

10

MHz

5.5V)

tCLCL

Oscillator Period (ATtiny25/45/85L, VCC = 2.7 -

100

ns

5.5V)

147

7598C–AVR–09/06