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USB to TTL (Serial) Adapters


D-SUN "USB to TTL" (Red)

(Rx & Tx use 3.3V logic levels)1

DSCN1740cs.jpg

DSCN1741cs.jpg

DSCN1742cs.jpg

lsusb

usb-devices
"MxPwr"

ID 10c4:ea60

Cygnal Integrated Products, Inc. CP210x UART Bridge / myAVR mySmartUSB light

100 mA

lsusb -t

/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dwc_otg/1p, 480M
    |__ Port 1: Dev 2, If 0, Class=hub, Driver=hub/3p, 480M
        |__ Port 1: Dev 3, If 0, Class=vend., Driver=smsc95xx, 480M
        |__ Port 3: Dev 4, If 0, Class=vend., Driver=cp210x, 12M

Simple "loopback" Test:

GtkTermRaspiRedUSB2TTYs.png

DSCN1745cs.jpg
DSCN1746cs.jpg

Logged in to raspigrey from a dual-boot netbook running Ubuntu Linux2

GtkTermRaspiGreySerialPortLogin_s.png

DSCN1754cs.jpg

DSCN1755cs.jpg

Logged in to raspigrey from the same netbook now running Windows XP

RaspiGreyHyperTerminalWinXP.png

D-SUN "USB to TTL" (Blue)

(Rx & Tx use 3.3V logic levels)

P1010446bcs.JPG

P1010447bcs.JPG

P1010453rcs.JPG

lsusb

usb-devices
"MxPwr"

ID 067b:2303

Prolific Technology, Inc. PL2303 Serial Port

100 mA

"JY" USB --> UART

(CP2102 based, Rx & Tx use 3.3V logic levels)

undercon.png

P1020381lrcs.JPG

P1020383rcs.JPG

BTE13-2007 "USB CP2102"

USB to UART Converter for Programming Shrimps and Arduinos (RxD, TxD, CTS & DTR use 3.3V logic levels)3

DSCN1765cs.jpg

DSCN1766cs.jpg

lsusb

usb-devices
"MxPwr"

ID 10c4:ea60

Cygnal Integrated Products, Inc. CP210x Composite Device

100 mA

lsusb -t

pi@raspiredNOOBS131 ~ $ lsusb -t
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dwc_otg/1p, 480M
    |__ Port 1: Dev 2, If 0, Class=hub, Driver=hub/3p, 480M
        |__ Port 1: Dev 3, If 0, Class=vend., Driver=smsc95xx, 480M
        |__ Port 3: Dev 4, If 0, Class=vend., Driver=cp210x, 12M

Simple "loopback" Test:

DSCN1769cs.jpg

TightVNC_GtkTerm_LoopBackTest_s.png

Logged in to raspigrey from a dual-boot netbook running Ubuntu Linux4

GtkTermRaspiGreyBTE13-007s.png

DSCN1781crs.jpg

Taylor Roco "USB TO TTL", CP2102, 6-pin

(RST, RXC & TXC use 3.3V logic levels)

P1020354cs.JPG

P1020355cs.JPG
P1020356rcs.JPG

lsusb

usb-devices
"MxPwr"

ID 10c4:ea60

Cygnal Integrated Products, Inc. CP210x UART Bridge / myAVR mySmartUSB light

100 mA

SODIAL(R) "uUSB TO TTL Module, CP2102, 6-pin

(DTR, RXI & TXO use 4.1V logic levels, 3V3 pin also at 4.1V!)

P1050793tcs.JPG

P1050793tcs.JPG

lsusb info. & Quick Loopback Test

lsusb_lsusb-t#1.png

P1050798rcs.JPG
LoopBackTest#1.png

CH340-based, 6-pin Devices

(Rx & Tx use ~3.7V logic levels!5)

Gikfun YP-02 USB to TTL

P1020381rrcs.JPG

P1020382rcs.JPG

MH USB to TTL

P1070714rcs.JPG

P1070715rcs.JPG

"Red" FTDI232 (FT232RL) USB 3.3V/5.0V TTL Serial Adapter

(Use 3.3V link with a Raspberry Pi)6

P1000019rcs.jpg

P1000020rcs.jpg

lsusb

usb-devices
"MxPwr"

ID 0403:6001

Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC

90 mA

Logged in to raspigrey from a dual-boot netbook running Ubuntu Linux7

RaspiGreyGtkTermFTDI232NwazetLimeKey_s.png

P1000025cs.jpg

"Blue" FT232RL USB 5.0V/3.3V TTL Serial Adapter

(Break 5V link and solder 3.3V link for use with a Raspberry Pi)8

P1000136rcs.JPG

P1000137rcrs.JPG

lsusb

usb-devices
"MxPwr"

ID 0403:6001

Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC

90 mA

RHX PL2303MDL (Black)

(Rx & Tx use 3.3V logic levels)9

P1000386rcs.JPG

P1000387rcs.JPG

lsusb

usb-devices
"MxPwr"

ID 067b:2303

Prolific Technology, Inc. PL2303 Serial Port

100 mA

Simple "loopback" Test:

P1000388cs.JPG

Logged in to raspigrey from a dual-boot netbook running Ubuntu Linux10

GtkTermUbuntuRaspigreyPL2303MDLs.png
P1000389rcs.JPG

BTE13-009

(NB: Uses 5V TTL levels, DO NOT connect directly to a Pi's GPIO!) admon-caution.png

P1010285cs.JPG

P1010286rcs.JPG

P1010287rcs.JPG

P1010288rcsa.jpg

Momentary switch A appears to operate
as a "Reset/Disconnect" switch




Toggle/Slide switch B only switches the
VC pin between 3V and 5V!

USB Console Stub

First Sample: June 2020

P1100544rcs.JPG

P1100545rcs.JPG

P1100546s.JPG

P1100547s.JPG

lsusb and lsusb -t

pi@raspiP4B4b-32GbP:~ $ lsusb
Bus 002 Device 002: ID 0951:1666 Kingston Technology DataTraveler 100 G3/G4/SE9 G2
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 005: ID 04d9:1503 Holtek Semiconductor, Inc. Keyboard
Bus 001 Device 004: ID 25a7:fa61  
Bus 001 Device 003: ID 1a40:0101 Terminus Technology Inc. Hub
Bus 001 Device 006: ID 3171:0035  
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
pi@raspiP4B4b-32GbP:~ $ lsusb -t
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 5000M
    |__ Port 1: Dev 2, If 0, Class=Mass Storage, Driver=usb-storage, 5000M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/1p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
        |__ Port 3: Dev 6, If 0, Class=Communications, Driver=cdc_acm, 12M
        |__ Port 3: Dev 6, If 1, Class=CDC Data, Driver=cdc_acm, 12M
        |__ Port 3: Dev 6, If 2, Class=Human Interface Device, Driver=, 12M
        |__ Port 4: Dev 3, If 0, Class=Hub, Driver=hub/4p, 480M
            |__ Port 3: Dev 5, If 0, Class=Human Interface Device, Driver=usbhid, 1.5M
            |__ Port 3: Dev 5, If 1, Class=Human Interface Device, Driver=usbhid, 1.5M
            |__ Port 1: Dev 4, If 0, Class=Human Interface Device, Driver=usbhid, 12M
            |__ Port 1: Dev 4, If 1, Class=Human Interface Device, Driver=usbhid, 12M

Extract from usb-devices

T:  Bus=01 Lev=02 Prnt=02 Port=02 Cnt=01 Dev#=  6 Spd=12  MxCh= 0
D:  Ver= 2.00 Cls=ef(misc ) Sub=02 Prot=01 MxPS= 8 #Cfgs=  1
P:  Vendor=3171 ProdID=0035 Rev=01.10
S:  Manufacturer=8086 Consultancy
S:  Product=USB Serial Stub
S:  SerialNumber=0126
C:  #Ifs= 3 Cfg#= 1 Atr=80 MxPwr=100mA
I:  If#=0x0 Alt= 0 #EPs= 1 Cls=02(commc) Sub=02 Prot=01 Driver=cdc_acm
I:  If#=0x1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=cdc_acm
I:  If#=0x2 Alt= 0 #EPs= 0 Cls=03(HID  ) Sub=00 Prot=00 Driver=(none)

GtkTerm_ttyACM0_#1.png

GtkTerm_ttyACM0_#2.png

pi@raspiP4B4b-32GbP:~ $ cat .gtktermrc 
[default]
port    = /dev/ttyS0
speed   = 9600
bits    = 8
stopbits        = 1
parity  = none
flow    = none
wait_delay      = 0
wait_char       = 255
rs485_rts_time_before_tx        = 30
rs485_rts_time_after_tx = 30
echo    = False
crlfauto        = False
font    = "Monospace 12"
term_block_cursor       = True
term_rows       = 80
term_columns    = 25
term_scrollback = 200
term_visual_bell        = True
term_foreground_red     = 0.660000
term_foreground_blue    = 0.660000
term_foreground_green   = 0.660000
term_foreground_alpha   = 1.000000
term_background_red     = 0.000000
term_background_blue    = 0.000000
term_background_green   = 0.000000
term_background_alpha   = 1.000000

[piconsole]
port    = /dev/ttyACM0
speed   = 115200
bits    = 8
stopbits        = 1
parity  = none
flow    = none
wait_delay      = 0
wait_char       = 255
rs485_rts_time_before_tx        = 30
rs485_rts_time_after_tx = 30
echo    = False
crlfauto        = False
font    = "Monospace 12"
term_block_cursor       = True
term_rows       = 80
term_columns    = 25
term_scrollback = 200
term_visual_bell        = True
term_foreground_red     = 0.660000
term_foreground_blue    = 0.660000
term_foreground_green   = 0.660000
term_foreground_alpha   = 1.000000
term_background_red     = 0.000000
term_background_blue    = 0.000000
term_background_green   = 0.000000
term_background_alpha   = 1.000000

Second Sample: May 2021

P1130364rcs.JPG
P1130366rcs.JPG

P1130365rcs.JPG

Homyl CH340G 3.3V/5V UART Serial Adapter

In and Out of the bags:

P1120025s.JPG

P1120026rcs.JPG

Jumpered for Loopback Test & 3.3V Operation

P1120028rcs.JPG

USB2SerialLoopbackTest.png

Testing with a Pi Zero

20210310_225812rrcs.jpg

USB2SerialP0Test#1s.jpg

lsusb and lsusb -t

pi@raspiP4B4b-32GbP:~ $ lsusb
Bus 002 Device 002: ID 174c:55aa ASMedia Technology Inc. Name: ASM1051E SATA 6Gb/s bridge, ASM1053E SATA 6Gb/s bridge, ASM1153 SATA 3Gb/s bridge, ASM1153E SATA 6Gb/s bridge
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 005: ID 1c4f:0002 SiGma Micro Keyboard TRACER Gamma Ivory
Bus 001 Device 004: ID 1ea7:0064 SHARKOON Technologies GmbH 
Bus 001 Device 006: ID 1a86:7523 QinHeng Electronics HL-340 USB-Serial adapter
Bus 001 Device 003: ID 1a40:0101 Terminus Technology Inc. Hub
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
pi@raspiP4B4b-32GbP:~ $ lsusb -t
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 5000M
    |__ Port 2: Dev 2, If 0, Class=Mass Storage, Driver=uas, 5000M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/1p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
        |__ Port 3: Dev 3, If 0, Class=Hub, Driver=hub/4p, 480M
            |__ Port 1: Dev 6, If 0, Class=Vendor Specific Class, Driver=ch341, 12M
            |__ Port 2: Dev 4, If 0, Class=Human Interface Device, Driver=usbhid, 12M
            |__ Port 4: Dev 5, If 1, Class=Human Interface Device, Driver=usbhid, 1.5M
            |__ Port 4: Dev 5, If 0, Class=Human Interface Device, Driver=usbhid, 1.5M

Extract from usb-devices

T:  Bus=01 Lev=03 Prnt=03 Port=00 Cnt=01 Dev#=  6 Spd=12  MxCh= 0
D:  Ver= 1.10 Cls=ff(vend.) Sub=00 Prot=00 MxPS= 8 #Cfgs=  1
P:  Vendor=1a86 ProdID=7523 Rev=02.64
S:  Product=USB Serial
C:  #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=98mA
I:  If#=0x0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=01 Prot=02 Driver=ch341


Summary Table (3.3V Devices Only)

Device

"Chipset"

Primary Pinout

"MxPwr"

Pi Zero
Power?11

DSUN "Red"

CP210x

+5V GND RXD TXD 3V312

100 mA

thumbs-up.png

DSUN "Blue"

PL2303

+5V GND RXD TXD 3V312

100 mA

thumbs-up.png

"JY" USB --> UART

CP2102

+5V GND RXD TXD 3V312

mA

BTE13-2007

CP210x

GND CTS 5V TXD RXD DTR

100 mA

Taylor Roco "USB TO TTL", CP2102, 6-pin

CP2102

GND RXC TXC 5V RST 3.3

100 mA

"Red" FTDI232

FT232

DTR RX TX VCC CTS GND

90 mA

"Blue" FTDI232

FT232

GND CTS VCC TX RX DTR

90 mA

"Black" RHX PL2303MDL

PL2303

GND TXD RXD VCC 3V3

100 mA

USB Console Stub

?

(5V/NC) (5V/NC) GND TXD RXD

100 mA

Homyl CH340G UART Serial Adapter

CH340G

(RTS) 5V 3V3 TXD RXD GND (CTS)

98 mA


Configuration of Serial Terminal Input within Raspbian Jessie + Pixel post-release of the Raspberry Pi Model P3B

The serial terminal is no longer enabled by default. It can be enabled by either using the Pixel desktop GUI version of raspi-config or, with care, manual editing of /boot/cmdline.txt, followed by a re-boot.

SerialTerminalConfig#1.png

SerialTerminalConfig#2.png

Similarily for Raspberry Pi OS ("Buster") for the P4B onwards

RasPiIFaceConfigBuster.png

P4B_Buster_Cmdline#1.png


  1. Hobby Components HCMODU0051 (1)

  2. More details of the "breakout board" can be found here (2)

  3. Supplied by phenoptix (3)

  4. More details of the LCD/Serial board can be found here (4)

  5. Even with VCC linked to 3V3 pin (5)

  6. Amazon link: http://www.amazon.co.uk/dp/B00HSXDGOE/ref=pe_385721_37986871_TE_item (6)

  7. via a Nwazet Key Lime Pi GPIO adapter (7)

  8. Amazon link: http://www.amazon.co.uk/gp/product/B00JGP1N10/ref=oh_details_o02_s00_i00?ie=UTF8&psc=1 (8)

  9. Amazon link: http://www.amazon.co.uk/gp/product/B00DEWBB4K/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1 (9)

  10. via this adapter (Gnd, Rx & Tx connections only) (10)

  11. via this adapter (5V, Gnd, Rx & Tx connected) (11)

  12. 4-wire direct Pi connection possible (12 13 14)


2022-11-25 21:40