Samsung S5PC100, User Manual, Page: 663 / 1863

S5PC100 USER’S MANUAL (REV1.0) I
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C-BUS INTERFACE
8.2-11
3.1 MULTI-MASTER I
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C-BUS CONTROL REGISTER
•
I2CCON0, R/W, Address = 0xEC10_0000
•
I2CCON1, R/W, Address = 0xEC20_0000
I2CCON Bit Description Reset Value
Acknowledge generation
(1) [7] I
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C-bus acknowledge enable bit.
0 = Disables
1 = Enables
In Tx mode, the I2CSDA is free in the ACK time.
In Rx mode, the I2CSDA is L in the ACK time.
0
Tx clock source
selection [6] Source clock of I
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C-bus transmit clock prescaler selection bit.
0 = I2CCLK = fPCLK /16
1= I2CCLK = fPCLK /512
0
Tx/Rx Interrupt (5) [5] I
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C-Bus Tx/Rx interrupt enable/ disable bit.
0 = Disables, 1 = Enables
0
Interrupt pending flag
(2) (3) [4] I
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C-bus Tx/Rx interrupt pending flag. This bit cannot be written
to 1. If this bit is read as 1, the I2CSCL is tied to L and the I
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C
is stopped. To resume the operation, clear this bit as 0.
0 = 1) No interrupt pending (If read).
2) Clear pending condition &
Resume the operation (If write).
1 = 1) Interrupt is pending (If read)
2) N/A (If write)
0
Transmit clock value (4) [3:0] I
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C-Bus transmit clock prescaler.
I
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C-Bus transmit clock frequency is determined by this 4-bit
prescaler value, according to the following formula:
Tx clock = I2CCLK/(I2CCON[3:0]+1).
Undefined
NOTES:
1. Interfacing with EEPROM, the ACK generation may be disabled before reading the last data in order to generate the
STOP condition in Rx mode.
2. An
I
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C-bus interrupt occurs 1)if a 1-byte transmits or receive operation is complete. in other word, ack period is finished.
2) If a general call or a slave address match occurs, or 3) if bus arbitration fails.
3. To adjust the setup time of SDA before SCL rising edge, I2CDS has to be written before clearing the I
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C interrupt
pending bit.
4. I2CCLK is determined by I2CCON[6].
Tx clock can vary by SCL transition time.
If I2CCON[6]=0, I2CCON[3:0]=0x0 or 0x1 is not available.
5. If the I2CCON[5]=0, I2CCON[4] does not operate correctly.
Therefore, It is recommended that you should set I2CCON[5]=1, although you does not use the I
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C interrupt.