 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
AT89C51RC2-3CSIM Datasheet(PDF) 79 Page - ATMEL Corporation |
|
|
|||||||||||||||||||||||||||||
AT89C51RC2-3CSIM Datasheet(HTML) 79 Page - ATMEL Corporation |
|
|
79 / 127 page  79 AT89C51RB2/RC2 4180C–8051–12/03 ONCE™ Mode (ON Chip Emulation) The ONCE mode facilitates testing and debugging of systems using AT89C51RB2/RC2 without removing the circuit from the board. The ONCE mode is invoked by driving cer- tain pins of the AT89C51RB2/RC2; the following sequence must be exercised: • Pull ALE low while the device is in reset (RST high) and PSEN is high. • Hold ALE low as RST is deactivated. While the AT89C51RB2/RC2 is in ONCE mode, an emulator or test CPU can be used to drive the circuit. Table 61 shows the status of the port pins during ONCE mode. Normal operation is restored when normal reset is applied. Table 61. External Pin Status during ONCE Mode ALE PSEN Port 0 Port 1 Port 2 Port 3 XTAL1/2 Weak pull-up Weak pull-up Float Weak pull-up Weak pull-up Weak pull-up Active |
|
Link URL |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link to Datasheet | 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
