ATA6613-EK Atmel, ATA6613-EK Datasheet - Page 91

• Manufacturer Part Number: ATA6613-EK
• Description: BOARD DEMO LIN-MCM FOR ATA6613
• Manufacturer: Atmel

Specifications of ATA6613-EK

• Main Purpose: Interface, LIN + MCU
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: ATA6613
• Primary Attributes: LIN-SBC (System-Basis-Chip) Transceiver, LIN 2.0, Voltage Regulator, Window Watchdog
• Secondary Attributes: 16 kB Flash, 4 Power Modes: Pre-Normal, Normal, Sleep, Silent, 48-QFN
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

6.10.2.2
6.10.2.3
6.10.2.4
9111H–AUTO–01/11
Toggling the Pin
Switching Between Input and Output
Reading the Pin Value
Writing a logic one to PINxn toggles the value of PORTxn, independent on the value of
DDRxn. Note that the SBI instruction can be used to toggle one single bit in a port.
When switching between tri-state ({DDxn, PORTxn} = 0b00) and output high ({DDxn,
PORTxn} = 0b11), an intermediate state with either pull-up enabled {DDxn, PORTxn} = 0b01)
or output low ({DDxn, PORTxn} = 0b10) must occur. Normally, the pull-up enabled state is fully
acceptable, as a high-impedant environment will not notice the difference between a strong
high driver and a pull-up. If this is not the case, the PUD bit in the MCUCR Register can be set
to disable all pull-ups in all ports.
Switching between input with pull-up and output low generates the same problem. The user
must use either the tri-state ({DDxn, PORTxn} = 0b00) or the output high state ({DDxn,
PORTxn} = 0b11) as an intermediate step.
Table 6-30
Table 6-30.
Independent of the setting of Data Direction bit DDxn, the port pin can be read through the
PINxn Register bit. As shown in
ceding latch constitute a synchronizer. This is needed to avoid metastability if the physical pin
changes value near the edge of the internal clock, but it also introduces a delay.
on page 92
pin value. The maximum and minimum propagation delays are denoted t
respectively.
DDxn
0
0
0
1
1
PORTxn
summarizes the control signals for the pin value.
shows a timing diagram of the synchronization when reading an externally applied
0
1
1
0
1
Port Pin Configurations
(in MCUCR)
PUD
X
X
X
0
1
Figure 6-23 on page
Output
Output
Input
Input
Input
I/O
Atmel ATA6612/ATA6613
Pull-up
Yes
No
No
No
No
90, the PINxn Register bit and the pre-
Comment
Tri-state (Hi-Z)
Pxn will source current if ext. pulled low.
Tri-state (Hi-Z)
Output Low (Sink)
Output High (Source)
pd,max
Figure 6-24
and t
pd,min
91