STPCI0180BTC3 STMICROELECTRONICS [STMicroelectronics], STPCI0180BTC3 Datasheet - Page 28

• Manufacturer Part Number: STPCI0180BTC3
• Description: PC Compatible Embedded Microprocessor
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

PIN DESCRIPTION
HSYNC Horizontal Synchronisation Pulse. This is
the horizontal synchronization signal from the
VGA controller.
VREF_DAC DAC Voltage reference. This pin is
an input driving the digital to analog converters.
This allows an external voltage reference source
to be used.
RSET Resistor Current Set. This is the reference
current input to the RAMDAC. Used to set the full-
scale output of the RAMDAC.
COMP Compensation. This is the RAMDAC com-
pensation pin. Normally, an external capacitor
(typically 10nF) is connected between this pin and
V
DDC[1:0] Direct Data Channel Serial Link. These
bidirectional pins are connected to CRTC register
3Fh to implement DDC capabilities. They conform
to I
collector output drivers which are internally con-
nected to V
They can instead be used for accessing I C devic-
es on board. DDC1 and DDC0 correspond to SCL
and SDA respectively.
28/55
DD
2
C electrical specifications, they have open-
to damp oscillations.
DD
through pull-up resistors.
Issue 1.1
3.2.14 FLAT PANEL INTERFACE SIGNALS
FPFRAME, Vertical Sync. pulse Output.
FPLINE, Horizontal Sync. Pulse Output.
DE, Data Enable.
R5-0, Red Output.
G5-0, Green Output.
B5-0, Blue Output .
ENAVDD Enable VDD of Flat Panel.
ENVCC Enable VCC of Flat Panel.
PWM PWM Back-Light Control.
3.2.15 MISCELLANEOUS
SPKRD Speaker Drive. This is the output to the
speaker and is the AND of the counter 2 output
with bit 1 of Port 61h and drives an external speak-
er driver. This output should be connected to a
7407 type high voltage driver.
SCAN_ENABLE Reserved . This pin is reserved
for Test and Miscellaneous functions. It has to be
set to ‘0’ or connected to ground in normal opera-
tion.
(Combined with Serial 1)