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Table of Contents
Silicon Labs cp2102
This is a high speed USB UART and a genuine item should easily attain 460800 baud in Linux or even higher.
BAITE module (pictured)
Transmit is labelled RXD and receive as TXD on this module.
CJMCU module
This module uses a cp2102 device incorrectly wired with 4v4 on their output pins instead of 3v3. This module is totally unreliable at 460800 baud.
A source on the web explains that the RESET pin is incorrectly pulled high to VUSB.
6 in 1 USB to TTL RS232 USB TTL to RS485
There is lot going on here and none has been tested. A diagram exists explaining the switches.
Mode Pin Function TTL Level Interface TXD TTL Transmit TTL Level Interface RXD TTL Receive TTL Level Interface GND TTL ground 232 Level Interface 232-TX 232 Transmit 232 Level Interface 232-RX 232 Receive 232 Level Interface GND 232 Ground 485 Level Interface A 485A+ 485 Level Interface B 485B- +5V Voltage Output +5V +5V Voltage Output 3.3 Voltage Output 3V3 3.3V Voltage Output DTR Output DTR Special Function RTS Output RTS Special Function
Linux
udev /dev/ttyCP2102
KERNEL=="ttyUSB*",\ ATTRS{idVendor}=="10c4",\ ATTRS{idProduct}=="ea60",\ ATTRS{serial}=="0001",\ GROUP="dialout",\ MODE="0660",\ RUN+="/bin/ln -sf %k /dev/ttyCP2102"
udev by-id
/dev/serial/by-id/usb-Silicon_Labs_CP2102_USB_to_UART_Bridge_Controller_0001-if00-port0
udev by-id is not supported by Pickle Microchip PIC ICSP.
Pickle Microchip PIC ICSP
Low Voltage Programming with VPP at 3V3
Separate data I/O connections (only supported option)
BAITE Cp2102 module PICMicro =================== ======== 3V3-------------------------------VDD GND-------------------------------VSS TX (RXD)--------------------------VPP RTS-------------------------------PGC DTR-----------1000R----------+----PGD | CTS--------------------------+
Configuration
DEVICE=TTY IFACE=/dev/ttyUSB0 SLEEP=0 BITRULES=0x001F