Specifications

7
AT83SND2CMP3
7524D–MP3–07/07
Table 7. UART Signal Description
Table 8. Keypad Interface Signal Description
Table 9. System Signal Description
Table 10. Power Signal Description
Signal
Name Type Description
Alternate
Function
RXD I/O
Receive Serial Data
RXD sends and receives data in serial I/O mode 0 and receives data in
serial I/O modes 1, 2 and 3.
P3.0
TXD O
Transmit Serial Data
TXD outputs the shift clock in serial I/O mode 0 and transmits data in
serial I/O modes 1, 2 and 3.
P3.1
Signal
Name Type Description
Alternate
Function
KIN0 I
Keypad Input Line
Holding this pin high or low for 24 oscillator periods triggers a keypad
interrupt.
-
Signal
Name Type Description
Alternate
Function
RST I
Reset Input
Holding this pin high for 64 oscillator periods while the oscillator is
running resets the device. The Port pins are driven to their reset
conditions when a voltage lower than V
IL
is applied, whether or not the
oscillator is running.
This pin has an internal pull-down resistor which allows the device to be
reset by connecting a capacitor between this pin and V
DD
.
Asserting RST when the chip is in Idle mode or Power-Down mode
returns the chip to normal operation.
-
TST I
Test Input
Test mode entry signal. This pin must be set to V
DD
.
-
Signal
Name Type Description
Alternate
Function
VDD PWR
Digital Supply Voltage
Connect these pins to +3V supply voltage.
-
VSS GND
Circuit Ground
Connect these pins to ground.
-
PVDD PWR
PLL Supply voltage
Connect this pin to +3V supply voltage.
-
PVSS GND
PLL Circuit Ground
Connect this pin to ground.
-
UVDD PWR
USB Supply Voltage
Connect this pin to +3V supply voltage.
-