Electronic Components Datasheet Search |
|
PCA9557DBG4 Datasheet(PDF) 7 Page - Texas Instruments |
|
PCA9557DBG4 Datasheet(HTML) 7 Page - Texas Instruments |
7 / 36 page Device Address 0 Slave Address 0 1 1 A2 A1 A0 R/W Fixed Programmable Control Register and Command Byte 0 0 0 0 B1 B0 0 0 PCA9557 www.ti.com.................................................................................................................................................... SCPS133I – DECEMBER 2005 – REVISED JUNE 2008 The address of the PCA9557 is shown in Figure 4. Figure 4. PCA9557 Address Address Reference INPUTS I2C BUS SLAVE ADDRESS A2 A1 A0 L L L 24 (decimal), 18 (hexadecimal) L L H 25 (decimal), 19 (hexadecimal) L H L 26 (decimal), 1A (hexadecimal) L H H 27 (decimal), 1B (hexadecimal) H L L 28 (decimal), 1C (hexadecimal) H L H 29 (decimal), 1D (hexadecimal) H H L 30 (decimal), 1E (hexadecimal) H H H 31 (decimal), 1F (hexadecimal) The last bit of the slave address defines the operation (read or write) to be performed. A high (1) selects a read operation, while a low (0) selects a write operation. Following the successful acknowledgment of the address byte, the bus master sends a command byte that is stored in the control register in the PCA9557. Two bits of this data byte state the operation (read or write) and the internal registers (input, output, polarity inversion or configuration) that will be affected. This register can be written or read through the I2C bus. The command byte is sent only during a write transmission. Once a new command byte has been sent, the register that was addressed continues to be accessed by reads until a new command byte has been sent. Figure 5. Control Register Bits Command Byte CONTROL REGISTER BITS COMMAND BYTE POWER-UP REGISTER PROTOCOL (HEX) DEFAULT B1 B0 0 0 0x00 Input Port Read byte xxxx xxxx 0 1 0x01 Output Port Read/write byte 0000 0000 1 0 0x02 Polarity Inversion Read/write byte 1111 0000 1 1 0x03 Configuration Read/write byte 1111 1111 Copyright © 2005–2008, Texas Instruments Incorporated Submit Documentation Feedback 7 Product Folder Link(s): PCA9557 |
Similar Part No. - PCA9557DBG4 |
|
Similar Description - PCA9557DBG4 |
|
|
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 |