The control of TV or Satellitereceiver setting can
be done by up to eight 8-bit PWM outputs, with a
frequency maximum of 23,437Hz at 8-bit resolution (INTCLK = 12MHz). Low resolutions with
higher frequencyoperationcan be programmed.
Inadditionthereis a3 channelAnalogtoDigitalConverterwithintegralsampleandhold,fast5.75µscon-
versiontimeand6-bitguaranteedresolution.
PIN DESCRIPTION
VSYNC.
VerticalSync.
Verticalvideosynchronisa-
tion inputto OSD. Positiveor negativepolarity.
HSYNC.
Horizontal Sync.
Horizontal video synchronisationinput to OSD. Positiveor negativepolarity.
PLLF.
PLL Filterinput.
Filterinput for the OSD for
PLL feed-back.
PLLR.
PLL Resistor connection pin.
For resistor
connectionto select the PLL gain adjust.
RESET.
Reset(input,active low).
TheST9is initialisedbytheResetsignal.WiththedeactivationofRESET, program execution begins from the Program
memory location pointedto bythe vectorcontained
in programmemorylocations00h and01h.
OSCIN, OSCOUT.
Oscillator (input and output).
These pins connect a parallel-resonant crystal
GENERALDESCRIPTION (Continued)
(24MHz maximum), or an external source to the
on-chipclockoscillatorandbuffer.OSCINis theinput ofthe oscillatorinverter andinternalclock generator; OSCOUT is the output of the oscillator
inverter.
AV
DD
. AnalogVDDof PLL. This pin must betied to
V
DD
externallyto theST9291.
V
DD
. MainPowerSupply Voltage(5V±10%)
V
SS
. Digital Circuit Ground.
P0.0-P0.7, P2.0-P2.5, P3.0-P3.7, P4.0-P4.7,
P5.0-P5.1(J suffix)
P0.0-P0.7, P1.0-P1.7, P2.0-P2.5, P3.0-P3.7,
P4.0-P4.7,P5.0-P5.3 (N suffix)
I/O Port Lines (In-
put/Output,TTLor CMOScompatible).
32/42lines
grouped into I/O ports, bit programmable under
programcontrolas generalpurposeI/O oras Alternate functions(see next section).
P4.0 - P4.7are high voltage(12V) open drainoutputs. Thevoltage inopen drainoutput modefor all
other I/Obits must not exceed V
DD
.
I/O PortAlternate Functions.
Each pin of the I/O ports of the ST9291 may assume software programmable Alternative Functionsas shownin the Pin ConfigurationDrawings.
Table1 shows the Functionsallocated to each I/O
Port pin.
ST9291
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