Rainbow Electronics MAX7358 User Manual
Page 12
MAX7356/MAX7357/MAX7358
1-to-8 I
2
C Bus Switches/Multiplexers with Bus
Lock-Up Detection, Isolation, and Notification
12
______________________________________________________________________________________
Available addresses depend on the hardware connec-
tions of pins A2, A1, and A0 as shown in Table 1.
The last bit following the slave address bit A0 on an I
2
C
command defines the operation to be performed. When
the last bit sets to logic 1, a read is selected while logic
0 selects a write operation.
Register Map (MAX7357/MAX7358)
The MAX7357 and MAX7358 have 7 registers (shown in
Table 2) that can be accessed through the I
2
C bus. The
MAX7357 powers up with all of these registers accessi-
ble. The initial register address counter is at 0x00. The
MAX7358 powers up in basic mode with only the switch
control register available. Writing to a MAX7358
changes only the contents of the switch control register.
By sending a unique I
2
C sequence to the MAX7358, all
7 registers become available.
Register Access Protocol (MAX7356)
Only the MAX7356 device address is required to gain
access to its registers. A typical I
2
C command to com-
municate with the MAX7356 starts with its device
address followed directly by data bytes.
A5
R/W
A6
A4
A3
A2
A1
A0
FIXED
PIN-SELECTABLE BITS
Figure 7. MAX7356/MAX7357/MAX7358 Slave Address
A2
CONNECTION
A1
CONNECTION
A0
CONNECTION
A6
A5
A4
A3
A2
A1
A0
GND
GND
GND
1
1
1
0
0
0
0
GND
GND
V
DD
1
1
1
0
0
0
1
GND
V
DD
GND
1
1
1
0
0
1
0
GND
V
DD
V
DD
1
1
1
0
0
1
1
V
DD
GND
GND
1
1
1
0
1
0
0
V
DD
GND
V
DD
1
1
1
0
1
0
1
V
DD
V
DD
GND
1
1
1
0
1
1
0
V
DD
V
DD
V
DD
1
1
1
0
1
1
1
Table 1. MAX7356/MAX7357/MAX7358 Switch Multiplexer Device Address
POR DEFAULT SETTING
REGISTER
NAME
B7 B6
B5 B4
B3
B2
B1 B0
ACCESS
Switch
Control
0
0
0
0
0
0
0
0
R/
W
Table 3. MAX7357 and MAX7358 Basic-
Mode Register Map
POR DEFAULT SETTING
REGISTER NAME
INTERNAL
ADDRESS
B7
B6
B5
B4
B3
B2
B1
B0
NEXT
ADDRESS
ACCESS
Switch Control
0x00
0
0
0
0
0
0
0
0
0x01
R/W
Configuration
0x01
0
0
0
0
0
0
0
1
0x02
R/W
Flush-Out Sequence
0x02
1
1
1
1
1
1
1
1
0x00 (W)
0x03 (R)
R/W
Lock-Up Indication
0x03
0
0
0
0
0
0
0
0
0x04
R
0x04
0
0
0
0
0
0
0
0
0x05
R
Traffic Prior to Lock-Up
0x05
0
0
0
0
0
0
0
0
0x06
R
Stuck High Fault
0x06
0
0
0
0
0
0
0
0
0x00
R
Table 2. MAX7357/MAX7358 Enhanced-Mode Register Map