Datasheet

1163
42023E–SAM–07/2013
ATSAM4L8/L4/L2
Maximum SPI Frequency, Master Output
The maximum SPI master output frequency is given by the following formula:
Where is the MOSI delay, USPI2 or USPI5 depending on CPOL and NCPHA. is
the maximum frequency of the SPI pins. refer to the I/O Pin Characteristics section for the maxi-
mum frequency of the pins. is the maximum frequency of the CLK_SPI. Refer to the SPI
chapter for a description of this clock.
Maximum SPI Frequency, Master Input
The maximum SPI master input frequency is given by the following formula:
Where is the MISO setup and hold time, USPI0 + USPI1 or USPI3 + USPI4 depending on
CPOL and NCPHA. is the SPI slave response time. refer to the SPI slave datasheet for
. is the maximum frequency of the CLK_SPI. Refer to the SPI chapter for a
description of this clock.
42.10.2.2 Slave mode
Figure 42-9. USART in SPI Slave Mode with (CPOL= 0 and CPHA= 1) or (CPOL= 1 and
CPHA= 0)
f
SPCKMAX
MIN f
PINMAX
1
SPIn
------------
f
CLKSPI
2×
9
-----------------------------
,(, )=
SPIn
f
PINMAX
f
CLKSPI
f
SPCKMAX
MIN
1
SPIn t
VALID
+
----------------------------------- -
f
CLKSPI
2×
9
-----------------------------(,)=
SPIn
T
VALID
T
VALID
f
CLKSPI
USPI7 USPI8
MISO
SPCK
MOSI
USPI6