Electronic Components Datasheet Search |
|
AT90S8535 Datasheet(PDF) 79 Page - ATMEL Corporation |
|
|
AT90S8535 Datasheet(HTML) 79 Page - ATMEL Corporation |
79 / 127 page 79 AT90S/LS8535 1041H–11/01 Port B As General Digital I/O All eight pins in Port B have equal functionality when used as digital I/O pins. PBn, general I/O pin: The DDBn bit in the DDRB register selects the direction of this pin. If DDBn is set (one), PBn is configured as an output pin. If DDBn is cleared (zero), PBn is configured as an input pin. If PORTBn is set (one) when the pin is configured as an input pin, the MOS pull-up resistor is activated. To switch the pull-up resistor off, the PORTBn has to be cleared (zero) or the pin has to be configured as an output pin. The port pins are tri-stated when a reset condition becomes active, even if the clock is not running. Note: n: 7,6…0, pin number. Alternate Functions of Port B The alternate pin configuration is as follows: • SCK – Port B, Bit 7 SCK: Master clock output, slave clock input pin for SPI channel. When the SPI is enabled as a slave, this pin is configured as an input regardless of the setting of DDB7. When the SPI is enabled as a master, the data direction of this pin is controlled by DDB7. When the pin is forced to be an input, the pull-up can still be controlled by the PORTB7 bit. See the description of the SPI port for further details. • MISO – Port B, Bit 6 MISO: Master data input, slave data output pin for SPI channel. When the SPI is enabled as a master, this pin is configured as an input regardless of the setting of DDB6. When the SPI is enabled as a slave, the data direction of this pin is controlled by DDB6. When the pin is forced to be an input, the pull-up can still be controlled by the PORTB6 bit. See the description of the SPI port for further details. • MOSI – Port B, Bit 5 MOSI: SPI Master data output, slave data input for SPI channel. When the SPI is enabled as a slave, this pin is configured as an input regardless of the setting of DDB5. When the SPI is enabled as a master, the data direction of this pin is controlled by DDB5. When the pin is forced to be an input, the pull-up can still be controlled by the PORTB5 bit. See the description of the SPI port for further details. • SS – Port B, Bit 4 SS: Slave port select input. When the SPI is enabled as a slave, this pin is configured as an input regardless of the setting of DDB4. As a slave, the SPI is activated when this pin is driven low. When the SPI is enabled as a master, the data direction of this pin is con- trolled by DDB4. When the pin is forced to be an input, the pull-up can still be controlled by the PORTB4 bit. See the description of the SPI port for further details. • AIN1 – Port B, Bit 3 AIN1, Analog Comparator Negative Input. When configured as an input (DDB3 is cleared [zero]) and with the internal MOS pull-up resistor switched off (PB3 is cleared [zero]), this pin also serves as the negative input of the on-chip Analog Comparator. During Power-down mode, the Schmitt trigger of the digital input is disconnected. This Table 31. DDBn Effects on Port B Pins DDBn PORTBn I/O Pull-up Comment 0 0 Input No Tri-state (high-Z) 0 1 Input Yes PBn will source current if ext. pulled low 1 0 Output No Push-pull Zero Output 1 1 Output No Push-pull One Output |
Similar Part No. - AT90S8535 |
|
Similar Description - AT90S8535 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | 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 |