Intel PXA26X User Manual
Page 363
Intel® PXA26x Processor Family Developer’s Manual
9-25
Inter-Integrated Circuit Bus Interface Unit
10
BEIE
BUS ERROR INTERRUPT ENABLE:
0 – Disable interrupt.
1 – Enables the I
2
C unit to interrupt the processor
for the following
I
2
C
bus errors:
• As a master transmitter, no ACK was detected after a byte was sent.
• As a slave receiver, the I
2
C unit generated a NAK pulse.
NOTE: Software is responsible for guaranteeing that misplaced START and STOP
conditions do not occur. See
Section 9.7, “Glitch Suppression Logic”
.
9
IRFIE
IDBR RECEIVE FULL INTERRUPT ENABLE:
0 – Disable interrupt.
1 – Enables the I
2
C unit to interrupt the processor when the IDBR receives a data byte
from the I
2
C bus.
8
ITEIE
IDBR TRANSMIT EMPTY INTERRUPT ENABLE:
0 – Disable interrupt.
1 – Enables the I
2
C unit to interrupt the processor after transmitting a byte onto the I
2
C
bus.
7
GCD
GENERAL CALL DISABLE:
0 – Enables the I
2
C unit to respond to general call messages.
1 – Disables I
2
C unit response to general call messages as a slave.
Must be set when the I
2
C unit sends a master mode general call message.
6
IUE
I
2
C UNIT ENABLE:
0 – Disables the unit and does not master any transactions or respond to any slave
transactions.
1 – Enables the I
2
C unit (defaults to slave-receive mode).
Software must ensure that the I
2
C bus is idle before it sets this bit.
5
SCLE
SCL ENABLE:
0 – Disables the I
2
C unit from driving the SCL line.
1 – Enables the I
2
C clock output for master mode operation.
4
MA
MASTER ABORT:
Generates a STOP without transmitting another data byte when the I
2
C unit is in master
mode.
0 – The I
2
C unit transmits STOP using the STOP ICR bit only.
1 – The I
2
C unit sends STOP without data transmission.
In master-transmit mode, after a data byte is sent, the ICR’s Transfer Byte bit is cleared and
IDBR Transmit Empty bit is set. When no more data bytes need to be sent, setting master
abort bit sends the STOP. The Transfer Byte bit (03) must remain clear.
In master-receive mode, when a NAK is sent without a STOP (STOP ICR bit was not set)
and the processor does not send a repeated START, setting this bit sends the STOP. Once
again, the Transfer Byte bit (03) must remain clear.
Table 9-11. I
2
C Control Register - ICR (Sheet 2 of 3)
Physical Address
4030_1690
I
2
C Control Register
I
2
C
Bit
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
R
ese
rved
FM
UR
SA
DIE
AL
D
IE
SSD
IE
BE
IE
IR
FIE
ITEIE
GC
D
IU
E
SC
L
E
MA
TB
AC
KNA
K
ST
O
P
ST
A
R
T
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0