SAM4L_14 Datasheet, PDF (149/176 Pages) ATMEL Corporation – Technology for Ultra-low Power Consumption

ATSAM4L8/L4/L2
Where SPIn is the MISO delay, SPI6 or SPI9 depending on CPOL and NCPHA. t_SETUP is the
SPI master setup time. refer to the SPI master datasheet for t_SETUP . f_PINMAX is the maximum
frequency of the SPI pins. refer to the I/O Pin Characteristics section for the maximum frequency
of the pins.
9.10.4
TWIM/TWIS Timing
Figure 9-64 shows the TWI-bus timing requirements and the compliance of the device with
them. Some of these requirements (t_r and t_f) are met by the device without requiring user inter-
vention. Compliance with the other requirements (t_HD-STA, t_SU-STA, t_SU-STO, t_HD-DAT, t_SU-DAT-TWI, t_LOW-
TWI^{, t}HIGH^{, and f}TWCK^{) requires user intervention through appropriate programming of the relevant}
TWIM and TWIS user interface registers. refer to the TWIM and TWIS sections for more
information.
Table 9-64. TWI-Bus Timing Requirements
Symbol
Parameter
t_r
TWCK and TWD rise time
Mode
Standard⁽¹⁾
Fast⁽¹⁾
Standard
t_f
TWCK and TWD fall time
Fast
t_HD-STA
Standard
(Repeated) START hold time
Fast
t_SU-STA
Standard
(Repeated) START set-up time
Fast
t_SU-STO STOP set-up time
Standard
Fast
t_HD-DAT
Data hold time
Standard
Fast
t_SU-DAT-TWI Data set-up time
Standard
Fast
t_SU-DAT
t_LOW-TWI TWCK LOW period
-
Standard
Fast
t_LOW
t_HIGH
TWCK HIGH period
-
Standard
Fast
f_TWCK
TWCK frequency
Standard
Fast
Minimum
Requirement
Device
-
20 + 0.1C_b
-
20 + 0.1C_b
4
t_clkpb
0.6
4.7
t_clkpb
0.6
4.0
4t_clkpb
0.6
0.3⁽²⁾
2t_clkpb
250
2t_clkpb
100
-
t_clkpb
4.7
4t_clkpb
1.3
-
t_clkpb
4.0
8t_clkpb
0.6
-
Maximum
Requirement
Device
Unit
1000
ns
300
300
ns
300
-
μs
-
μs
3.45⁽⁾
0.9⁽⁾
100
400
-
μs
15t_prescaled + t_clkpb μs
-
ns
-
-
-
μs
-
-
-
μs
-----------1------------
kHz
12tclkpb
Notes: 1. Standard mode: f_TWCK ≤ 100 kHz ; fast mode: f_TWCK > 100 kHz .
42023GS–SAM–03/2014
149