EFM32WG Datasheet, PDF (434/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

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Bit
14
13:12
11:10
9:8
7
6
5
4
3
2
Name
Reset
Access Description
When set, the bus automatically goes idle on a bus idle timeout, allowing new transfers to be initiated.
Value
0
1
Description
A bus idle timeout has no effect on the bus state.
A bus idle timeout tells the I²C module that the bus is idle, allowing new transfers to be initiated.
Reserved
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)
BITO
0x0
RW
Bus Idle Timeout
Use to generate a timeout when SCL has been high for a given amount time between a START and STOP condition. When in a
bus transaction, i.e. the BUSY flag is set, a timer is started whenever SCL goes high. When the timer reaches the value defined
by BITO, it sets the BITO interrupt flag. The BITO interrupt flag will then be set periodically as long as SCL remains high. The bus
idle timeout is active as long as BUSY is set. It is thus stopped automatically on a timeout if GIBITO is set. It is also stopped a
STOP condition is detected and when the ABORT command is issued. The timeout is activated whenever the bus goes BUSY, i.e.
a START condition is detected.
Value
0
1
2
3
Mode
OFF
40PCC
80PCC
160PCC
Description
Timeout disabled
Timeout after 40 prescaled clock cycles. In standard mode at 100 kHz, this results in
a 50us timeout.
Timeout after 80 prescaled clock cycles. In standard mode at 100 kHz, this results in
a 100us timeout.
Timeout after 160 prescaled clock cycles. In standard mode at 100 kHz, this results
in a 200us timeout.
Reserved
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)
CLHR
0x0
RW
Clock Low High Ratio
Determines the ratio between the low and high parts of the clock signal generated on SCL as master.
Value
0
1
2
Reserved
Mode
STANDARD
ASYMMETRIC
FAST
Description
The ratio between low period and high period counters (N_low:N_high) is 4:4
The ratio between low period and high period counters (N_low:N_high) is 6:3
The ratio between low period and high period counters (N_low:N_high) is 11:6
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)
GCAMEN
0
RW
General Call Address Match Enable
Set to enable address match on general call in addition to the programmed slave address.
Value
0
1
Description
General call address will be NACK'ed if it is not included by the slave address and address mask.
When a general call address is received, a software response is required.
ARBDIS
0
RW
Arbitration Disable
A master or slave will not release the bus upon losing arbitration.
Value
0
1
Description
When a device loses arbitration, the ARB interrupt flag is set and the bus is released.
When a device loses arbitration, the ARB interrupt flag is set, but communication proceeds.
AUTOSN
0
RW
Automatic STOP on NACK
Write to 1 to make a master transmitter send a STOP when a NACK is received from a slave.
Value
0
1
Description
Stop is not automatically sent if a NACK is received from a slave.
The master automatically sends a STOP if a NACK is received from a slave.
AUTOSE
0
RW
Automatic STOP when Empty
Write to 1 to make a master transmitter send a STOP when no more data is available for transmission.
Value
0
1
Description
A stop must be sent manually when no more data is to be transmitted.
The master automatically sends a STOP when no more data is available for transmission.
AUTOACK
0
RW
Set to enable automatic acknowledges.
Automatic Acknowledge
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
434
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