Nxp Semiconductors UM10237 ユーザーズマニュアル

UM10237_2

© NXP B.V. 2008. All rights reserved.

The I2CONCLR registers control clearing of bits in the I2CON register that controls 
operation of the I

2

C interface. Writing a one to a bit of this register causes the 

corresponding bit in the I

2

C control register to be cleared. Writing a zero has no effect.

 

AAC is the Assert Acknowledge Clear bit. Writing a 1 to this bit clears the AA bit in the 
I2CONSET register. Writing 0 has no effect.

SIC is the I

2

C Interrupt Clear bit. Writing a 1 to this bit clears the SI bit in the I2CONSET 

register. Writing 0 has no effect.

STAC is the Start flag Clear bit. Writing a 1 to this bit clears the STA bit in the I2CONSET 
register. Writing 0 has no effect.

I2ENC is the I

2

C Interface Disable bit. Writing a 1 to this bit clears the I2EN bit in the 

I2CONSET register. Writing 0 has no effect.

Each I

2

C Status register reflects the condition of the corresponding I

2

C interface. The I

2

C 

Status register is Read-Only.

 

The three least significant bits are always 0. Taken as a byte, the status register contents 
represent a status code. There are 26 possible status codes. When the status code is 
0xF8, there is no relevant information available and the SI bit is not set. All other 25 status 
codes correspond to defined I

2

C states. When any of these states entered, the SI bit will 

be set. For a complete list of status codes, refer to tables from 

 to 

1:0 -

Reserved. User software should not write ones to reserved bits. The 
value read from a reserved bit is not defined.

NA

2

AAC

Assert acknowledge Clear bit.

3

SIC

I

2

C interrupt Clear bit.

0

4

-

Reserved. User software should not write ones to reserved bits. The 
value read from a reserved bit is not defined.

NA

5

STAC

START flag Clear bit.

0

6

I2ENC

I

2

C interface Disable bit.

0

7

-

Reserved. User software should not write ones to reserved bits. The 
value read from a reserved bit is not defined.

NA

2:0 -

These bits are unused and are always 0.

0

7:3 Status

These bits give the actual status information about the I

2

C interface. 0x1F