 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
AT89LP6440 Datasheet(PDF) 118 Page - ATMEL Corporation |
|
|
|||||||||||||||||||||||||||||
AT89LP6440 Datasheet(HTML) 118 Page - ATMEL Corporation |
|
|
118 / 194 page  118 3706A–MICRO–9/09 AT89LP6440 - Preliminary TWEN must be written to one to enable the Two-wire Serial Interface, STA must be written to one to transmit a START condition and TWIF must be cleared. The TWI will then test the Two- wire Serial Bus and generate a START condition as soon as the bus becomes free. After a START condition has been transmitted, the TWIF flag is set by hardware, and the status code in TWSR will be 08h (see Table 18-7). In order to enter MR mode, SLA+R must be transmitted. This is done by writing SLA+R to TWDR. Thereafter the TWIF bit should be cleared to continue the transfer. When SLA+R has been transmitted and an acknowledgment bit has been received, TWIF is set again and a number of status codes in TWSR are possible. Possible status codes in Master mode are 38h, 40h or 48h. The appropriate action to be taken for each of these status codes is detailed in Table 18-7. Received data can be read from the TWDR Register when the TWIF flag is set high by hardware. This scheme is repeated until the last byte has been received. After the last byte has been received, the MR should inform the ST by sending a NACK after the last received data byte. The transfer is ended by generating a STOP condition or a repeated START condition. Table 18-7. Status Codes for Master Receiver Mode Status Code (TWSR) Status of the Two-wire Serial Bus and Two-wire Serial Interface Hardware Application Software Response Next Action Taken by TWI Hardware To/from TWDR To TWCR STA STO TWIF AA 08h A START condition has been transmitted Load SLA+R 0 0 1 X SLA+R will be transmitted; ACK or NOT ACK will be received 10h A repeated START condition has been transmitted Load SLA+R 0 0 1 X SLA+R will be transmitted; ACK or NOT ACK will be received Load SLA+W 0 0 1 X SLA+W will be transmitted; Logic will switch to Master Transmitter mode 38h Arbitration lost in SLA+R or NOT ACK bit No action 0 0 1 X Two-wire Serial Bus will be released and not addressed Slave mode will be entered No action 1 0 1 X A START condition will be transmitted when the bus becomes free 40h SLA+R has been transmitted; ACK has been received No action 0 0 1 0 Data byte will be received and NOT ACK will be returned No action 0 0 1 1 Data byte will be received and ACK will be returned 48h SLA+R has been transmitted; NOT ACK has been received No action 1 0 1 X Repeated START will be transmitted No action 0 1 1 X STOP condition will be transmitted and STO flag will be reset No action 1 1 1 X STOP condition followed by a START condition will be transmitted and STO flag will be reset 50h Data byte has been received; ACK has been returned Read data byte 0 0 1 0 Data byte will be received and NOT ACK will be returned Read data byte 0 0 1 1 Data byte will be received and ACK will be returned 58h Data byte has been received; NOT ACK has been returned Read data byte 1 0 1 X Repeated START will be transmitted Read data byte 0 1 1 X STOP condition will be transmitted and STO flag will be reset Read data byte 1 1 1 X STOP condition followed by a START condition will be transmitted and STO flag will be reset |
|
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
