AN311 Datasheet | Silicon Labs

Features The CP2120 incorporates a number of features not found in the SC18IS60x. SPI Master firmware can take advantage of these added features to create a more efficient and reliable system. Rev. 0.1 9/06 Copyright © 2006 by Silicon Laboratories 2.1.1. 256-Byte Data Buffers The CP2120 uses 256-byte data buffers to send and receive bytes with SMBus slaves. Calls to the Write Number of Bytes mand can transmit up to 255 bytes in a single transaction, while calls to Read Number of Bytes can store up to 255 bytes of data into a buffer that can then be read by a Read Buffer mand call. The Write After Write mand, which transmits to one slave address and then immediately transmits to a second slave address, can transmit any amount of data as long as the sum of the two buffers’ sizes does not exceed 255 bytes. The Read After Write mand can write 255 bytes and then immediately receive 255 bytes, which can then be retrieved by the SPI Master during a Read Buffer call. The Write To Multiple Slaves mand can write to any number of slaves any data buffer size, as long as the number of slaves listed in the mand plus the number of bytes stored in the data buffer does not exceed 255. 2.1.2. 8 General Purpose I/O Pins .. The CP2120 offers 8 general purpose input/output port pins that can be configured to either output or input using the IOCONFIG and IOCONFIG2 Internal Registers. Writes to the...