LM8322JGR8 NSC [National Semiconductor], LM8322JGR8 Datasheet - Page 24

• Manufacturer Part Number: LM8322JGR8
• Description: Mobile I/O Companion Supporting Key-Scan, I/O Expansion, PWM, and ACCESS.bus Host Interface
• Manufacturer: NSC [National Semiconductor]

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15.0 Digital Multiplexers
Two 2:1 multiplexers are provided for host-controlled digital
switching. Setting the MUX1EN or MUX2EN bits with the
WRITE_CFG command enables the corresponding multi-
plexer and its input and output signals, which overrides any
other functions which may use these pins. The MUX1 signals
are alternate functions of the PWM_x outputs. The MUX2
signals are alternate functions of three KP-Yx pins.
The data select inputs for the multiplexers are controlled by
the MUX1SEL and MUX2SEL bits, which are written by the
WRITE_CFG command. If it is important to avoid momentarily
passing an incorrect input to the output, the select bit must be
loaded with a first WRITE_CFG command before sending a
second WRITE_CFG command to set the enable bit. The
truth table for the multiplexers is shown in Table 9.
24
MUXxE
N Bit
1
1
1
1
0
TABLE 9. Digital Multiplexer Function Table
MUXxSEL
Bit
X
0
0
1
1
MUXx_IN
Pin
X
X
X
2
0
1
MUXx_IN
Pin
X
X
X
1
0
1
not enabled
MUXx_OU
MUXx_OU
Pin
T
0
1
0
1
T