 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
PCA9564 Datasheet(PDF) 7 Page - NXP Semiconductors |
|
||||||||||||||||||||||||||||||
PCA9564 Datasheet(HTML) 7 Page - NXP Semiconductors |
|
|
7 / 32 page  Philips Semiconductors Product data sheet PCA9564 Parallel bus to I2C-bus controller 2006 Sep 01 7 More Information on SIO Operating Modes The four operating modes are: – Master Transmitter – Master Receiver – Slave Receiver – Slave Transmitter Data transfers in each mode of operation are shown in Figures 2–5. These figures contain the following abbreviations: Abbreviation Explanation S Start condition SLA 7-bit slave address R Read bit (HIGH level at SDA) W Write bit (LOW level at SDA) A Acknowledge bit (LOW level at SDA) A Not acknowledge bit (HIGH level at SDA) Data 8-bit data byte P Stop condition In Figures 2-5, circles are used to indicate when the serial interrupt flag is set. A serial interrupt is not generated when I2CSTA = F8H. This happens on a stop condition. The numbers in the circles show the status code held in the I2CSTA register. At these points, a service routine must be executed to continue or complete the serial transfer. These service routines are not critical since the serial transfer is suspended until the serial interrupt flag is cleared by software. When a serial interrupt routine is entered, the status code in I2CSTA is used to branch to the appropriate service routine. For each status code, the required software action and details of the following serial transfer are given in Tables 2-6. Master Transmitter Mode: In the master transmitter mode, a number of data bytes are transmitted to a slave receiver (see Figure 2). Before the master transmitter mode can be entered, I2CCON must be initialized as follows: I2CCON ENSIO STA STO SI CR1 CR0 7 65 4 3 2 1 0 10 0 0 X bit rate CR2 AA ENSIO must be set to logic 1 to enable SIO. If the AA bit is reset, SIO will not acknowledge its own slave address in the event of another device becoming master of the bus. In other words, if AA is reset, SIO cannot enter a slave mode. STA, STO, and SI must be reset. The master transmitter mode may now be entered by setting the STA bit. The SIO logic will now test the I2C-bus and generate a start condition as soon as the bus becomes free. When a START condition is transmitted, the serial interrupt flag (SI) is set, and the status code in the status register (I2CSTA) will be 08H. This status code must be used to vector to an interrupt service routine that loads I2CDAT with the slave address and the data direction bit (SLA+W). The SI bit in I2CCON must then be reset before the serial transfer can continue. When the slave address and the direction bit have been transmitted and an acknowledgment bit has been received, the serial interrupt flag (SI) is set again, and a number of status codes in I2CSTA are possible. There are 18H, 20H, or 38H for the master mode and also 68H, or B0H if the slave mode was enabled (AA = logic 1). The appropriate action to be taken for each of these status codes is detailed in Table 2. After a repeated start condition (state 10H). SIO may switch to the master receiver mode by loading I2CDAT with SLA+R). Note that a master should never transmit its own slave address. Master Receiver Mode: In the master receiver mode, a number of data bytes are received from a slave transmitter (see Figure 3). The transfer is initialized as in the master transmitter mode. When the start condition has been transmitted, the interrupt service routine must load I2CDAT with the 7-bit slave address and the data direction bit (SLA+R). The SI bit in I2CCON must then be cleared before the serial transfer can continue. When the slave address and the data direction bit have been transmitted and an acknowledgment bit has been received, the serial interrupt flag (SI) is set again, and a number of status codes in I2CSTA are possible. These are 40H, 48H, or 38H for the master mode and also 68H, or B0H if the slave mode was enabled (AA = logic 1). The appropriate action to be taken for each of these status codes is detailed in Table 3. ENSIO is not affected by the serial transfer and are not referred to in Table 3. After a repeated start condition (state 10H), SIO may switch to the master transmitter mode by loading I2CDAT with SLA+W. Note that a master should not transmit its own slave address. Slave Receiver Mode: In the slave receiver mode, a number of data bytes are received from a master transmitter (see Figure 4). To initiate the slave receiver mode, I2CADR and I2CCON must be loaded as follows: I2CADR 0 7 65 43 2 1 0 own slave address BIT7 BIT6 BIT5 BIT4 BIT3 BIT2 BIT1 The upper 7 bits are the address to which SIO will respond when addressed by a master. I2CCON ENSIO STA STO SI 7 65 4 3 2 1 0 11 0 0 0 X X X AA CR1 CR0 CR2 ENSIO must be set to logic 1 to enable SIO. The AA bit must be set to enable SIO to acknowledge its own slave address, STA, STO, and SI must be reset. When I2CADR and I2CCON have been initialized, SIO waits until it is addressed by its own slave address followed by the data direction bit which must be “0” (W) for SIO to operate in the slave receiver mode. After its own slave address and the W bit have been received, the serial interrupt flag (I) is set and a valid status code can be read from I2CSTA. This status code is used to vector to an interrupt service routine, and the appropriate action to be taken for each of these status codes is detailed in Table 4. The slave receiver mode may also be entered if arbitration is lost while SIO is in the master mode (see status 68H). If the AA bit is reset during a transfer, SIO will return a not acknowledge (logic 1) to SDA after the next received data byte. While AA is reset, SIO does not respond to its own slave address. However, the I2C-bus is still monitored and address recognition may be resumed at any time by setting AA. This means that the AA bit may be used to temporarily isolate SIO from the I2C-bus. |
Similar Part No. - PCA9564 |
|
Similar Description - PCA9564 |
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.NET |
| 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
