MAN - CAN AVR - UK - 5.00

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ITALIAN TECHNOLOGY

SERIAL COMMUNICATION SELECTION

Serial communication line of CAN AVR can be buffered as RS 232 or TTL.

By software, it is possible to define physical communicatin protocol for the line setting some microcontroller internal registers.

The serial interface has its own group of registers for configuration, and can work in total independence respect to the other peripherals.

Electric protocol is selected by hardware and requires the dip switches to be configured correctly, as described in previous tables; the user can set any configuration in autonomy following the below reported information:

- SERIAL LINE USART0 CONFIGURED AS RS 232 (default configuration)

DSW1.1

= ON

DSW1.2

= ON

DSW1.3

= ON

DSW1.4

= OFF

DSW1.5

= OFF

- SERIAL LINE USART0 CONFIGURED AS TTL

DSW1.1

= OFF

DSW1.2

= OFF

DSW1.3

= OFF

DSW1.4

= ON

DSW1.5

= ON

Figures 10 and 11 show how to connect a generic external system to both serial lines of CAN AVR.

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CAN AVR Rel. 5.00

ITALIAN TECHNOLOGY grifo

®

3 RXD0 USART0 (set as RS232)

4

TXD0 USART0 (set as RS232)

14 GND

F

IGURE

10: E

XAMPLE OF

RS 232

SERIAL CONNECTION

TX

RX

GND

4

3 RXD0 USART0 (set as TTL)

TXD0 USART0 (set as TTL)

14 GND

TX

RX

GND

F

IGURE

11: E

XAMPLE OF

TTL

SERIAL CONNECTION

CAN AVR Rel. 5.00

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