Datasheet

7
4341H–MP3–10/07
AT8xC51SND2C/MP3B
Table 4-4. Audio Interface Signal Description
Table 4-5. USB Controller Signal Description
Table 4-6. MutiMediaCard Interface Signal Description
INT1 I
Timer 1 Gate Input
INT1 serves as external run control for timer 1, when selected by GATE1 bit in
TCON register.
External Interrupt 1
INT1 input sets IE1 in the TCON register. If bit IT1 in this register is set, bit IE1
is set by a falling edge on INT1#. If bit IT1 is cleared, bit IE1 is set by a low
level on INT1#.
P3.3
T0 I
Timer 0 External Clock Input
When timer 0 operates as a counter, a falling edge on the T0 pin increments
the count.
P3.4
T1 I
Timer 1 External Clock Input
When timer 1 operates as a counter, a falling edge on the T1 pin increments
the count.
P3.5
Signal
Name Type Description
Alternate
Function
DCLK O DAC Data Bit Clock -
DOUT O DAC Audio Data Output -
DSEL O
DAC Channel Select Signal
DSEL is the sample rate clock output.
-
SCLK O
DAC System Clock
SCLK is the oversampling clock synchronized to the digital audio data (DOUT)
and the channel selection signal (DSEL).
-
Signal
Name Type Description
Alternate
Function
D+ I/O
USB Positive Data Upstream Port
This pin requires an external 1.5 KΩ pull-up to V
DD
for full speed operation.
-
D- I/O USB Negative Data Upstream Port -
Signal
Name Type Description
Alternate
Function
MCLK O
MMC Clock output
Data or command clock transfer.
-
MCMD I/O
MMC Command line
Bidirectional command channel used for card initialization and data transfer
commands. To avoid any parasitic current consumption, unused MCMD input
must be polarized to V
DD
or V
SS
.
-
MDAT I/O
MMC Data line
Bidirectional data channel. To avoid any parasitic current consumption, unused
MDAT input must be polarized to V
DD
or V
SS
.
-
Signal
Name Type Description
Alternate
Function