Datasheet
• Flexible message buffers (MBs), totalling up to 16 message buffers of 0–8 bytes data length each, configurable as Rx
or Tx, all supporting standard and extended messages
• Listen-only mode capability
• Individual mask registers for each message buffer
• Programmable transmit-first scheme: lowest ID or lowest buffer number
• Timestamp based on 16-bit free-running timer
• Global network time, synchronized by a specific message
4.5.7.6 Serial Peripheral Interface (SPI)
• Master and slave mode
• Full-duplex, three-wire synchronous transfers
• Programmable transmit bit rate
• Double-buffered transmit and receive data registers
• Serial clock phase and polarity options
• Slave select output
• Mode fault error flag with CPU interrupt capability
• Control of SPI operation during wait mode
• Selectable MSB-first or LSB-first shifting
• Programmable 8-bit or 16-bit data transmission length
• Receive data buffer hardware match feature
• 64-bit FIFO mode for high speed transfers of large amounts of data
• Support for both transmit and receive by DMA
4.5.7.7 Inter-Integrated Circuit (I
2
C)
• Compatible with I
2
C bus standard and SMBus Specification Version 2 features
• Up to 100 kbps with maximum bus loading
• Multi-master operation
• Software programmable for one of 64 different serial clock frequencies
• Programmable slave address and glitch input filter
• Interrupt or DMA driven byte-by-byte data transfer
• Arbitration lost interrupt with automatic mode switching from master to slave
• Calling address identification interrupt
• Bus busy detection broadcast and 10-bit address extension
• Address matching causes wake-up when processor is in low power mode
4.5.7.8 UART
• Support for ISO 7816 protocol for interfacing with smartcards
• Full-duplex operation
• Standard mark/space non-return-to-zero (NRZ) format
• Selectable IrDA 1.4 return-to-zero-inverted (RZI) format with programmable pulse width
• 13-bit baud rate selection with fractional divide of 32
• Programmable 8-bit or 9-bit data format
• Separately enabled transmitter and receiver
• Programmable transmitter output polarity
• Programmable receive input polarity
• 13-bit break character option
• 11-bit break character detection option
• Parameterizable buffer support for one dataword for each transmit and receive
• Independent FIFO structure for transmit and receive
• Two receiver wakeup methods:
Communication interfaces
K20 Family Product Brief, Rev. 11, 08/2012
44 Freescale Semiconductor, Inc.