ATtiny25/45/85
	Table 22-10. Serial Programming Instruction Set
					Instruction Format
	Instruction			Byte 1	Byte 2		Byte 3	Byte4	Operation
				0101 0000	0000	1000	xxxx xxxx	oooo oooo	Read Extended Fuse bits. “0” = pro-
	Read Extended Fuse Bits								grammed, “1” = unprogrammed. See
									Table 22-3 on page 150 for details.
	Read Calibration Byte			0011 1000	000x	xxxx	0000 0000	oooo oooo	Read Calibration Byte
				1111 0000	0000	0000	xxxx xxxx	xxxx xxxo	If o = “1”, a programming operation is
	Poll RDY/BSY								still busy. Wait 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 85°C, VCC = 1.8 - 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 - 5.5V)	100			ns
1/tCLCL	Oscillator Frequency (ATtiny25/45/85, VCC = 4.5V -	0		20	MHz
	5.5V)
tCLCL	Oscillator Period (ATtiny25/45/85, VCC = 4.5V - 5.5V)	50			ns
tSHSL	SCK Pulse Width High	2 tCLCL*			ns
tSLSH	SCK Pulse Width Low	2 tCLCL*			ns
tOVSH	MOSI Setup to SCK High	tCLCL			ns
tSHOX	MOSI Hold after SCK High	2 tCLCL			ns
tSLIV	SCK Low to MISO Valid	TBD	TBD	TBD	ns
Note: 1.	2 tCLCL for fck < 12 MHz, 3 tCLCL for fck >= 12 MHz

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