 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
ST72321BXXX-AUTO Datasheet(PDF) 47 Page - STMicroelectronics |
|
|
|||||||||||||||||||||||||||||
ST72321BXXX-AUTO Datasheet(HTML) 47 Page - STMicroelectronics |
|
|
47 / 247 page  ST72321Bxxx-Auto Supply, reset and clock management 47/247 The RESET service routine vector is fixed at addresses FFFEh-FFFFh in the ST7 memory map. The basic RESET sequence consists of three phases as shown in Figure 12: ● Active phase depending on the RESET source ● 256 or 4096 CPU clock cycle delay (selected by option byte) ● RESET vector fetch Caution: When the ST7 is unprogrammed or fully erased, the Flash is blank and the RESET vector is not programmed. For this reason, it is recommended to keep the RESET pin in low state until programming mode is entered, in order to avoid unwanted behavior. The 256 or 4096 CPU clock cycle delay allows the oscillator to stabilize and ensures that recovery has taken place from the Reset state. The shorter or longer clock cycle delay should be selected by option byte to correspond to the stabilization time of the external oscillator used in the application (see Section 21.1.1: Flash configuration on page 228). The RESET vector fetch phase duration is 2 clock cycles. Figure 11. Reset block diagram Figure 12. RESET sequence phases 6.5.2 Asynchronous external RESET pin The RESET pin is both an input and an open-drain output with integrated RON weak pull-up resistor. This pull-up has no fixed value but varies in accordance with the input voltage. It can be pulled low by external circuitry to reset the device. See Section 19.9: Control pin characteristics on page 211 for more details. A RESET signal originating from an external source must have a duration of at least th(RSTL)in in order to be recognized (see Figure 13). This detection is asynchronous and therefore the MCU can enter reset state even in Halt mode. RESET RON VDD WATCHDOG RESET LVD RESET INTERNAL RESET PULSE GENERATOR Filter RESET ACTIVE PHASE INTERNAL RESET 256 or 4096 CLOCK CYCLES FETCH VECTOR |
Similar Part No. - ST72321BXXX-AUTO |
|
Similar Description - ST72321BXXX-AUTO |
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.COM |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| 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 Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
