Motor de Búsqueda de Datasheet de Componentes Electrónicos
Selected language     Spanish  ▼

Delete All
ON OFF
ALLDATASHEET.ES

X  

Preview PDF Download HTML

ST6262C Datasheet(PDF) 22 Page - STMicroelectronics

No. de Pieza. ST6262C
Descripción  8-BIT OTP/EPROM MCUs WITH A/D CONVERTER, SAFE RESET, AUTO-RELOAD TIMER AND EEPROM
Descarga  78 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Fabricante  STMICROELECTRONICS [STMicroelectronics]
Página de inicio  http://www.st.com
Logo 

ST6262C Datasheet(HTML) 22 Page - STMicroelectronics

Zoom Inzoom in Zoom Outzoom out
 22 / 78 page
background image
22/78
ST62T52C ST62T62C/E62C
3.2 RESETS
The MCU can be reset in four ways:
– by the external Reset input being pulled low;
– by Power-on Reset;
– by the digital Watchdog peripheral timing out.
– by Low Voltage Detection (LVD)
3.2.1 RESET Input
The RESET pin may be connected to a device of
the application board in order to reset the MCU if
required. The RESET pin may be pulled low in
RUN, WAIT or STOP mode. This input can be
used to reset the MCU internal state and ensure a
correct start-up procedure. The pin is active low
and features a Schmitt trigger input. The internal
Reset signal is generated by adding a delay to the
external signal. Therefore even short pulses on
the RESET pin are acceptable, provided VDD has
completed its rising phase and that the oscillator is
running correctly (normal RUN or WAIT modes).
The MCU is kept in the Reset state as long as the
RESET pin is held low.
If RESET activation occurs in the RUN or WAIT
modes, processing of the user program is stopped
(RUN mode only), the Inputs and Outputs are con-
figured as inputs with pull-up resistors and the
main Oscillator is restarted. When the level on the
RESET pin then goes high, the initialization se-
quence is executed following expiry of the internal
delay period.
If RESET pin activation occurs in the STOP mode,
the oscillator starts up and all Inputs and Outputs
are configured as inputs with pull-up resistors.
When the level of the RESET pin then goes high,
the initialization sequence is executed following
expiry of the internal delay period.
3.2.2 Power-on Reset
The function of the POR circuit consists in waking
up the MCU by detecting around 2V a dynamic
(rising edge) variation of the VDD Supply. At the
beginning of this sequence, the MCU is configured
in the Reset state: all I/O ports are configured as
inputs with pull-up resistors and no instruction is
executed. When the power supply voltage rises to
a sufficient level, the oscillator starts to operate,
whereupon an internal delay is initiated, in order to
allow the oscillator to fully stabilize before execut-
ing the first instruction. The initialization sequence
is executed immediately following the internal de-
lay.
To ensure correct start-up, the user should take
care that the VDD Supply is stabilized at a suffi-
cient level for the chosen frequency (see recom-
mended operation) before the reset signal is re-
leased. In addition, supply rising must start from
0V.
As a consequence, the POR does not allow to su-
pervise static, slowly rising, or falling, or noisy
(presenting oscillation) VDD supplies.
An external RC network connected to the RESET
pin, or the LVD reset can be used instead to get
the best performances.
Figure 13. Reset and Interrupt Processing
INT LATCH CLEARED
NMI MASK SET
RESET
( IF PRESENT )
SELECT
NMI MODE FLAGS
IS RESET STILL
PRESENT?
YES
PUT FFEH
ON ADDRESS BUS
FROM RESET LOCATIONS
FFE/FFF
NO
FETCH INSTRUCTION
LOAD PC
VA000427


Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39  40  41  42  43  44  45  46  47  48  49  50  51  52  53  54  55  56  57  58  59  60  61  62  63  64  65  66  67  68  69  70  71  72  73  74  75  76  77  78 


Datasheet Download




Enlace URL




Privacy Policy
ALLDATASHEET.ES
Does ALLDATASHEET help your business so far?  [ DONATE ]  

Todo acerca de Alldatasheet   |   Publicidad   |   Contáctenos   |   Política de Privacidad   |   Favorito   |   Intercambio de Enlaces   |   Lista de Fabricantes
All Rights Reserved© Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn