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340
8272E–AVR–04/2013
ATmega164A/PA/324A/PA/644A/PA/1284/P
Figure 28-4. SPI interface timing requirements (Slave mode).
28.7
two-wire Serial Interface Characteristics
Ta ble 28 -16 descr ib es th e r equirem ents fo r d evice s con nected to the two-wire Se r i al Bus. T he Atm e l
ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P two-wire Serial Interface meets or exceeds these require-
ments under the noted conditions.
MISO
(Data Output)
SCK
(CPOL = 1)
MOSI
(Data Input)
SCK
(CPOL = 0)
SS
MSB
LSB
MSB
...
10
11
12
13
14
17
15
9
X
16
Table 28-16. two-wire serial bus requirements.
Symbol
Parameter
Condition
Min.
Max.
Units
V
IL
Input Low-voltage
-0.5
0.3V
CC
V
IH
Input High-voltage
0.7 V
CC
V
CC + 0.5
Vhys
Hysteresis of Schmitt Trigger Inputs
0.05 VCC
–
V
OL
Output Low-voltage
3mA sink current
0
0.4
t
r
Rise Time for both SDA and SCL
20 + 0.1C
b
300
ns
tof
Output Fall Time from VIHmin to VILmax
10pF < Cb < 400pF
20 + 0.1Cb
250
t
SP
Spikes Suppressed by Input Filter
0
Ii
Input Current each I/O Pin
0.1VCC < Vi < 0.9VCC
-10
10
A
Ci
Capacitance for each I/O Pin
–
10
pF
f
SCL
SCL Clock Frequency
f
SCL, 250kHz)
0
400
kHz
Rp
Value of Pull-up resistor
fSCL 100kHz
fSCL > 100kHz
t
HD;STA
Hold Time (repeated) START Condition
fSCL 100kHz
4.0
–
s
fSCL > 100kHz
0.6
–
tLOW
Low Period of the SCL Clock
f
SCL 100kHz
4.7
–
fSCL > 100kHz
1.3
–
V
CC
0.4V
–
3mA
----------------------------
1000ns
C
b
-------------------
V
CC
0.4V
–
3mA
----------------------------
300ns
C
b
----------------