ATA6613-EK Atmel, ATA6613-EK Datasheet - Page 10

• 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

3.1.10
3.1.11
3.1.12
3.1.13
10
ATA6612/ATA6613
NRES Output Pin (LIN SBC) and PC6/NRES Input Pin (Microcontroller)
PB6 and PB7 (Microcontroller)
Other Pins
Summary of the Hard-wired Pins on the ATA6612/ATA6613 - EK
The NRES output pin is an open-drain output and therefore it requires an external pull-up
resistor to VCC. The PC6/NRES input pin has already a pull-up resistor included with a resis-
tance between 30 k and 60 k . The NRES output pin of the LIN SBC is connected to the
NRES input pin (PC6) of the microcontroller via the jumper “NRES”. For normal operation, this
jumper has to be set so that a reset signal generated from the LIN SBC will reset the micro-
controller. As removing this jumper would lead to an undefined value at the NRES output pin,
an additional 10 k resistor has been provided on the development board.
As the NRES output is an open-drain output it is not necessary to remove the jumper NRES
during programming or debugging the device.
The microcontroller runs on an internal RC-oscillator with a default frequency of 1 MHz. As the
accuracy of the internal clock is sufficient for LIN communication, in most cases there is no
need for higher accuracy. However, for some applications a more accurate clock is required
and therefore an external crystal oscillator can be mounted on the development board at the
designated placeholder Q1 together with the required capacitors C7 and C8 (please refer also
to Running the Microcontroller on External Clock). Please note, that when activating the exter-
nal clock, the fuse bit setting has to be changed. For more information about how to change
the fuse bits and information on using an external clock, refer to the datasheet of the
ATA6612/ATA6613 and to the AVR Studio documentation.
If no external clock is used, the two pins PB6 and PB7 can be used as normal I/O-pins without
any restriction.
All remaining pins not described in this section do not have any special external circuitry
and/or they are used as described in details in the datasheet.
As already described in detail in the previous sections, there are some pins tied together on
the development board in hand.
Table 3-1.
The three connections marked in bold are generated via jumpers and the other two connec-
tions are generated via 0 resistors and equipped with a test point and therefore easy to
access.
Microcontroller Pin
Summary of the Hard-wired Pins on the ATA6612/ATA6613 - EK
PC6/NRES
PD3
PD4
PD1
PD0
Table 3-1
gives a summary of these pins.
Connected to LIN SBC Pin
NTRIG
NRES
RXD
TXD
EN
9127A–AUTO–05/08