最後更新: 2023-10-04

目錄

• stty

CH340

USB to serial port control chip

lsusb | grep CH340

Bus 003 Device 004: ID 1a86:7523 QinHeng Electronics CH340 serial converter

dmsg

... usb 3-13: ch341-uart converter now attached to ttyUSB0

lsmod | grep ch34

ch341                  28672  0
usbserial              61440  1 ch341

Troubleshoot

情況

stty -F /dev/ttyUSB0

stty: /dev/ttyUSB0: Inappropriate ioctl for device

原因

After unplugging the USB device, the "/dev/ttyUSB?" file still exists

Fix

rmmod ch341
rm /dev/ttyUSB? -f
modprobe ch341

STM8S103F

Spec

• 8-bit MCU, 16MHz
• Program memory: 8KBytes
• Data memory: 640 Bytes # EEPROM
• RAM: 1 KBytes

Program memory(ROM) vs data memory

應用

LCUS-4

Serial Port Settings: 9600bps

狀態查詢:

發送 0xff 到 serial port

echo -n -e '\xFF' > /dev/ttyUSB0
cat -A /dev/ttyUSB0

CH1: OFF\r\nCH2: OFF\r\n

Open / Close

Open1: A0 01 01 A2
Close1: A0 01 00 A1
Open2: A0 02 01 A3
Close2: A0 02 00 A2

i.e. 將 CH1: ON

echo -n -e '\xA0\x01\x01\xA2' > /dev/ttyUSB0

cat -A /dev/ttyUSB0

CH1: ON $
$
CH2: OFF$
$