32.6 SPI Timing Characteristics

Table 32-8. SPI Timing Parameters

Description	Mode	Min.	Typ	Max	Units
SCK period	Master	-	See Table. Relationship Between SCK and the Oscillator Frequency in "SPCR – SPI Control Register"	-	ns
SCK high/low	Master	-	50% duty cycle	-
Rise/Fall time	Master	-	3.6	-
Setup	Master	-	10	-
Hold	Master	-	10	-
Out to SCK	Master	-	0.5 • tsck	-
SCK to out	Master	-	10	-
SCK to out high	Master	-	10	-
SS low to out	Slave	-	15	-
SCK period	Slave	4 • tck	-	-
SCK high/low(1)	Slave	2 • tck	-	-
Rise/Fall time	Slave	-	-	1600
Setup	Slave	10	-	-
Hold	Slave	tck	-	-
SCK to out	Slave	-	15	-
SCK to SS high	Slave	20	-	-
SS high to tri-state	Slave	-	10	-
SS low to SCK	Slave	2 • tck	-	-

Note:

1. In SPI Programming mode the minimum SCK high/low period is:


• 2 t_CLCL for f_CK < 12MHz

• 3 t_CLCL for f_CK > 12MHz