Digi NS9215 manual E x t e r n a l a d d r e s s e s, Slave Description Addres Bit

Models: NS9215

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I 2 C M A S T E R / S L A V E I N T E R F A C E

I2C external addresses

serial clock. Serial clock modulation can be controlled by both the transmitter and receiver, based in their hosts’ service speed.

Multi-master bus The I2C is a true multi-master bus with collision detection and arbitration to prevent data corruption when two or more masters initiate transfer simultaneously. If a master loses arbitration during the addressing stage, it is possible that the winning master is trying to address the transfer. The losing master must therefore immediately switch over to its slave mode.

The on-chip filtering rejects spikes on the bus data line to preserve data integrity. The number of ICs that can be connected to the same bus is limited only by a maximum bus capacity of 400 pf.

I 2 C e x t e r n a l a d d r e s s e s

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I2C external [bus] addresses are allocated as two groups of eight addresses (0000XXX and 1111XXX)

:

Slave

R/W

Description

addres

bit

 

 

 

 

0000 000

0

General call address

 

 

 

0000 000

1

START byte (not supported in the processor)

 

 

 

0000 001

X

CBUS address (not supported in the processor)

 

 

 

0000 010

X

Reserved for different bus format

 

 

 

0000 011

X

Reserved

 

 

 

0000 1xx

X

hs-mode master code (not supported in the

 

 

processor)

 

 

 

1111 1xx

X

Reserved

 

 

 

1111 0xx

X

10-bit slave address

 

 

 

The general call address is for addressing all devices connected to the I2C bus. A device can ignore this address by not issuing an acknowledgement. The meaning of the general call address is always specified in the second byte.

448Hardware Reference NS9215

Page 448
Image 448
Digi NS9215 manual E x t e r n a l a d d r e s s e s, Slave Description Addres Bit