10-10
MPC8240 Integrated Processor User’s Manual
I
2
C Register Descriptions
10.3.3 I
2
C Control Register (I2CCR)
The I2CCR controls the modes of the I
2
C interface, and is shown in Figure 10-5.
Figure 10-5. I
2
C Control Register (I2CCR)
Table 10-3 describes the bit settings of the I2CCR.
Table 10-6. I2CCR Field Descriptions—Offset 0x0_3008
Bits
Name
Reset
Value
R/W
Description
31–8
—
R
Reserved
7
MEN
0
R/W
Module enable. This bit controls the software reset of the I
2
C module.
0 The module is reset and disabled. When low, the interface is held in reset. In this
state, all the registers except I2CDR can still be accessed.
1 The I
2
C module is enabled. This bit must be set before any other control register
bits have any effect. All I
2
C registers for slave receive or master START can be
initialized before setting this bit. Refer to Section 10.2.6, “Arbitration Procedure.”
6
MIEN
0
R/W
Module interrupt enable
0 Interrupts from the I
2
C module are disabled. This does not clear any pending
interrupt conditions.
1 Interrupts from the I
2
C module are enabled. When an interrupt condition occurs,
an interrupt (int) is generated, provided I2CSR[MIF] is also set.
5
MSTA
0
R/W
Master/slave mode START
0 Slave mode. When this bit is changed from a 1 to 0, a STOP condition is
generated and the mode changes from master to slave.
1 Master mode. When this bit is changed from a 0 to 1, a START condition is
generated on the bus, and the master mode is selected.
The MSTA bit is cleared without generating a STOP condition when the master
loses arbitration. See Section 10.2.6, “Arbitration Procedure.”
4
MTX
0
R/W
Transmit/receive mode select. This bit selects the direction of the master and slave
transfers. When configured as a slave, this bit should be set by software according
to I2CSR[SRW]. In master mode, the bit should be set according to the type of
transfer required. Therefore, for address cycles, this bit will always be high.
0 Receive mode
1 Transmit mode
The MTX bit is cleared when the master loses arbitration.
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
31
8
7
6
5
4
3
2
1
0
Reserved
MEN
MIEN
MSTA
MTX
TXAK
RSTA
Summary of Contents for MPC8240
Page 1: ...MPC8240UM D Rev 1 1 2001 MPC8240 Integrated Processor User s Manual ...
Page 38: ...xviii MPC8240 Integrated Processor User s Manual TABLES Table Number Title Page Number ...
Page 48: ...xlviii MPC8240 Integrated Processor User s Manual Acronyms and Abbreviations ...
Page 312: ...6 94 MPC8240 Integrated Processor User s Manual ROM Flash Interface Operation ...
Page 348: ...7 36 MPC8240 Integrated Processor User s Manual PCI Host and Agent Modes ...
Page 372: ...8 24 MPC8240 Integrated Processor User s Manual DMA Register Descriptions ...
Page 394: ...9 22 MPC8240 Integrated Processor User s Manual I2O Interface ...
Page 412: ...10 18 MPC8240 Integrated Processor User s Manual Programming Guidelines ...
Page 454: ...12 14 MPC8240 Integrated Processor User s Manual Internal Arbitration ...
Page 466: ...13 12 MPC8240 Integrated Processor User s Manual Exception Latencies ...
Page 516: ...16 14 Watchpoint Trigger Applications ...
Page 538: ...B 16 MPC8240 Integrated Processor User s Manual Setting the Endian Mode of Operation ...
Page 546: ...C 8 MPC8240 Integrated Processor User s Manual ...
Page 640: ...INDEX Index 16 MPC8240 Integrated Processor User s Manual ...