ST10F269-T3 STMicroelectronics, ST10F269-T3 Datasheet - Page 107

• Manufacturer Part Number: ST10F269-T3
• Manufacturer: STMicroelectronics

Specifications of ST10F269-T3

• Cpu Family: ST10
• Device Core Size: 16b
• Frequency (max): 32MHz
• Interface Type: ASC/I2C/SSC
• Program Memory Type: Flash
• Program Memory Size: 256KB
• Total Internal Ram Size: 12KB
• # I/os (max): 111
• Number Of Timers - General Purpose: 4
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 4.5V
• On-chip Adc: 16-chx10-bit
• Instruction Set Architecture: CISC/RISC
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 144
• Package Type: TQFP
• Lead Free Status / Rohs Status: Supplier Unconfirmed

18 - SYSTEM RESET
System reset initializes the MCU in a predefined state. There are five ways to activate a reset state. The
system start-up configuration is different for each case as shown in Table 28.
Table 28 : Reset Event Definition
18.1 - Long Hardware Reset
The reset is triggered when RSTIN pin is pulled low, then the MCU is immediately forced in reset default
state. It pulls low RSTOUT pin, it cancels pending internal hold states if any, it aborts external bus cycle, it
switches buses (data, address and control signals) and I/O pin drivers to high-impedance, it pulls high PORT0
pins and the reset sequence starts.
To get a long hardware reset, the duration of the external RSTIN signal must be longer than 1040 TCL.
The level of RPD pin is sampled during the whole RSTIN pulse duration. A low level on RPD pin
determines an asynchronous reset while a high level leads to a synchronous reset.
Note
18.1.1 - Asynchronous Reset
Figure 54 and Figure 55 show asynchronous reset condition (RPD pin is at low level).
Figure 54 : Asynchronous Reset Sequence External Fetch
Note: 1) RSTIN rising edge to internal latch of PORT0 is 3 CPU clock cycles (6 TCL) if the PLL is bypassed and the prescaler is on
Power-on reset
Long Hardware reset (synchronous & asynchronous)
Short Hardware reset (synchronous reset)
Watchdog Timer reset
Software reset
(f
CPU
A reset can be entered as synchronous and exit as asynchronous if V
RPD pin threshold (typically 2.5V for V
internally pulled low.
RSTIN
= f
CPU Clock
RPD
RSTOUT
ALE
RD
PORT0
Internal reset
XTAL
/ 2), else it is 4 CPU clock cycles (8 TCL).
Reset Source
Reset Condition
Asynchronous
Reset Configuration
1
6 or 8 TCL
2
DD
3
= 5V) when RSTIN pin is low or when RSTIN pin is
1)
4
5
5 TCL
Short-cut
Latching point of PORT0
for system start-up
configuration
SHWR
LHWR
WDTR
PONR
6
SWR
7
8
9
Power-on
t
4 TCL < t
WDT overflow
SRST execution
RSTIN
1st Instruction External Fetch
> 1040 TCL
RPD
RSTIN
EXTERNAL FETCH
voltage drops below the
Conditions
< 1038 TCL
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