User manual
...the world's most energy friendly microcontrollers
2012-04-24 - Giant Gecko Family - d0053_Rev0.96 437
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16.5.3 I2Cn_STATE - State Register
Offset Bit Position
0x008
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Reset
0x0
0
0
0
0
1
Access
R
R
R
R
R
R
Name
STATE
BUSHOLD
NACKED
TRANSMITTER
MASTER
BUSY
Bit Name Reset Access Description
31:8 Reserved
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)
7:5 STATE 0x0 R Transmission State
The state of any current transmission. Cleared if the I
2
C module is idle.
Value Mode Description
0 IDLE No transmission is being performed.
1 WAIT Waiting for idle. Will send a start condition as soon as the bus is idle.
2 START Start transmitted or received
3 ADDR Address transmitted or received
4 ADDRACK Address ack/nack transmitted or received
5 DATA Data transmitted or received
6 DATAACK Data ack/nack transmitted or received
4 BUSHOLD 0 R Bus Held
Set if the bus is currently being held by this I
2
C module.
3 NACKED 0 R Nack Received
Set if a NACK was received and STATE is ADDRACK or DATAACK.
2 TRANSMITTER 0 R Transmitter
Set when operating as a master transmitter or a slave transmitter. When cleared, the system may be operating as a master receiver,
a slave receiver or the current mode is not known.
1 MASTER 0 R Master
Set when operating as an I
2
C master. When cleared, the system may be operating as an I
2
C slave.
0 BUSY 1 R Bus Busy
Set when the bus is busy. Whether the I
2
C module is in control of the bus or not has no effect on the value of this bit. When the
MCU comes out of reset, the state of the bus is not known, and thus BUSY is set. Use the ABORT command or a bus idle timeout
to force the I
2
C module out of the BUSY state.
16.5.4 I2Cn_STATUS - Status Register
Offset Bit Position
0x00C
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Reset
0
1
0
0
0
0
0
0
0
Access
R
R
R
R
R
R
R
R
R
Name
RXDATAV
TXBL
TXC
PABORT
PCONT
PNACK
PACK
PSTOP
PSTART
Bit Name Reset Access Description
31:9 Reserved
To ensure compatibility with future devices, always write bits to 0. More information in Section 2.1 (p. 3)