xr20m1172 串口扩展芯片 Linux 驱动
The XR20M11721 is a high performance two channel
universal asynchronous receiver and transmitter
(UART) with 64 byte TX and RX FIFOs and a
selectable I2C/SPI slave interface. The XR20M1172
operates from 1.62 to 3.63 volts. The standard
features include 16 selectable TX and RX FIFO
trigger levels, automatic hardware (RTS/CTS) and
software (Xon/Xoff) flow control, and a complete
modem interface. Onboard registers provide the user
with operational status and data error flags. An
internal loopback capability allows system
diagnostics. Additional enhanced features includes a
programmable fractional baud rate generator and 8X
and 4X sampling rate that allows for a maximum baud
rate of 16 Mbps at 3.3V. The XR20M1172 is available
in the 32-pin QFN and 28-pin TSSOP packages. The
32-pin QFN package has the EN485# and ENIR#
pins to allow the UART to power-up in the Auto
RS485 mode or the Infrared mode.
