ST6200 STMICROELECTRONICS [STMicroelectronics], ST6200 Datasheet - Page 19

• Manufacturer Part Number: ST6200
• Description: 8-BIT MCUs WITH A/D CONVERTER, TWO TIMERS, OSCILLATOR SAFEGUARD & SAFE RESET
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

CLOCK SYSTEM (Cont’d)
5.1.1 Main Oscillator
The oscillator configuration is specified by select-
ing the appropriate option in the option bytes (refer
to the Option Bytes section of this document).
When the CRYSTAL/RESONATOR option is se-
lected, it must be used with a quartz crystal, a ce-
ramic resonator or an external signal provided on
the OSCin pin. When the RC NETWORK option is
selected, the system clock is generated by an ex-
ternal resistor (the capacitor is implemented inter-
nally).
The main oscillator can be turned off (when the
OSG ENABLED option is selected) by setting the
OSCOFF bit of the ADC Control Register (not
available on some devices). This will automatically
start the Low Frequency Auxiliary Oscillator
(LFAO).
The main oscillator can be turned off by resetting
the OSCOFF bit of the A/D Converter Control Reg-
ister or by resetting the MCU. When the main os-
cillator starts there is a delay made up of the oscil-
lator start-up delay period plus the duration of the
software instruction at a clock frequency f
Caution: It should be noted that when the RC net-
work option is selected, the accuracy of the fre-
quency is about 20% so it may not be suitable for
some applications (For more details, please refer
to the Electrical Characteristics Section).
LFAO
.
Table 5. Oscillator Configurations
Notes:
1. To select the options shown in column 1 of the above
table, refer to the Option Byte section.
2.This schematic are given for guidance only and are sub-
ject to the schematics given by the crystal or ceramic res-
onator manufacturer.
3. For more details, please refer to the Electrical Charac-
teristics Section.
C
L1
Hardware Configuration
EXTERNAL
ST6200C/ST6201C/ST6203C
Crystal/Resonator Clock
OSCin
CLOCK
NC
OSCin
OSCin
OSCin
CAPACITORS
External Clock
RC Network
LFAO
LOAD
ST6
ST6
ST6
ST6
R
NET
OSCout
OSCout
OSCout
OSCout
NC
NC
3)
C
2)
L2
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