ST72215G2 STMicroelectronics, ST72215G2 Datasheet - Page 19

• Manufacturer Part Number: ST72215G2
• Description: 8-BIT MCU WITH SINGLE VOLTAGE FLASH MEMORY,ADC, 16-BIT TIMERS, SPI, I2C INTERFACES
• Manufacturer: STMicroelectronics

Specifications of ST72215G2

• Emulation Voltage: 5.5 V

6.2 RESET SEQUENCE MANAGER (RSM)
6.2.1 Introduction
The reset sequence manager includes three RE-
SET sources as shown in
■
■
■
These sources act on the RESET pin and it is al-
ways kept low during the delay phase.
The RESET service routine vector is fixed at ad-
dresses FFFEh-FFFFh in the ST7 memory map.
The basic RESET sequence consists of 3 phases
as shown in
■
■
■
Figure 11. Reset Block Diagram
External RESET source pulse
Internal LVD RESET (Low Voltage Detection)
Internal WATCHDOG RESET
Delay depending on the RESET source
4096 CPU clock cycle delay
RESET vector fetch
RESET
Figure
10:
Figure
V
DD
R
ON
11:
f
CPU
ST72104Gx, ST72215Gx, ST72216Gx, ST72254Gx
The 4096 CPU clock cycle delay allows the oscil-
lator to stabilise and ensures that recovery has
taken place from the Reset state.
The RESET vector fetch phase duration is 2 clock
cycles.
Figure 10. RESET Sequence Phases
DELAY
4096 CLOCK CYCLES
INTERNAL RESET
RESET
WATCHDOG RESET
LVD RESET
INTERNAL
RESET
VECTOR
FETCH
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