Write N Bytes As A Slave; General Call Address; General Call Address Second Byte Definitions; Slave Mode Programming Examples - Intel IXP45X Developer's Manual

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• Sets the ISR general call address detected bit
• Sets the ISR slave address detected bit
• Interrupts (when enabled) the IXP45X/IXP46X network processors
2
If the I
set, the I
Figure 204. General Call Address
STAR T
Ma ste r t o S la ve
Table 281.

General Call Address Second Byte Definitions

Least
Significant Bit
of Second
Byte (B)
0
0
0
NOTE: Other values are not fixed and must be ignored.
Software must ensure that the I
must also ensure that the I
directed to reset, the I
The CPU is responsible for ensuring this occurs, not the I
hardware.
When B=1, the sequence is a hardware general call and is not supported by the I
unit. Refer to the I
2
I C 10-bit addressing and CBUS compatibility are not supported.
21.6

Slave Mode Programming Examples

21.6.1 Initialize Unit
1. Write ISAR: Set slave address.
2. Write ICR: Enable all interrupts.
3. Set ICR[Unit Enable] bit to enable the I
21.6.2

Write n Bytes as a Slave

1. When a Slave Address Detected interrupt occurs.
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Intel IXP45X and Intel IXP46X Product Line of Network Processors
Developer's Manual
892
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IXP45X and Intel IXP46X Product Line of Network Processors—I2C Bus Interface Unit
C unit receives a general call address and the ICR General Call Disable bit is
2
C unit ignores the general call address.
00 00 00 00 AC K Seco nd Byte
First B yte
S lave to Ma ster
Second Byte
Value
2-byte transaction where the second byte tells the slave to reset and
06H
then store this value in the programmable part of their slave address.
2-byte transaction where the second byte tells the slave to store this
04H
value in the programmable part of their slave address. No reset.
00H Not allowed as a second byte
2
C bus is idle when the unit is enabled after reset. When
2
C Bus Interface Unit will return to its default reset condition.
2
C-Bus Specification for information on hardware general calls.
Da ta
A CK
0
Byt e
Seco nd Byte
L east Sign ifican t Bit of M a ster Ad dress
D e fines Tran sactio n
2
C unit is not busy before it asserts a reset. Software
2
C unit.
D ata
A C K AC K
B yte
N B ytes + A C K
Definition
2
C Bus Interface Unit
Order Number: 306262-004US
STOP
B4270-01
2
C
August 2006