USB TTL cable no longer working

USB TTL cable no longer working - Printable Version

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USB TTL cable no longer working - taros - 03-09-2016

My serial cable no longer works. It used to work.

I connect it to the Euler connector,

Quote:TX: pin 29
RX: pin 30
GND: pin 34

Then on Linux,

Code:
cu -l /dev/ttyUSB0 -s 115200

I do not get any response from "cu".
I tried two such cables. Is it possible that the cables got damaged? What can done to deal with this?
Initially I was worried that I bricked the board. However, I managed to boot an image off the microSD card, that had HDMI output.

RE: USB TTL cable no longer working - janjwerner - 03-09-2016

Have you tried the UART pins on the EXP port? I guess everything is wired to same place, but maybe there is some issue with a a connector.

RE: USB TTL cable no longer working - tllim - 03-09-2016

(03-09-2016, 12:09 PM)janjwerner Wrote: Have you tried the UART pins on the EXP port? I guess everything is wired to same place, but maybe there is some issue with a a connector.

Better use EXP port for UART console cable. The Euler port UART pin has voltage shifter and Euler port do not.

RE: USB TTL cable no longer working - peterz - 03-09-2016

(03-09-2016, 01:36 PM)tllim Wrote:
(03-09-2016, 12:09 PM)janjwerner Wrote: Have you tried the UART pins on the EXP port? I guess everything is wired to same place, but maybe there is some issue with a a connector.

Better use EXP port for UART console cable. The Euler port UART pin has voltage shifter and Euler port do not.

According pinout there is possible to have 6 UARTS (I plan to test this once I have my PINE64 in hands together with modules based on MAX3232 chip from ebay).
https://drive.google.com/a/pine64.com/file/d/0B0cEs0lxTtL3YU1CNmJ2bEIzTlE/view?usp=sharing

1 of UARTs is on PI bus. I'd try this.
pin6 - GND
pin8 - UART_TXD
pin10 - UART_RXD

But don't know what device file each UART will have.
Try check what device files are there containing "tty" under /dev .

RE: USB TTL cable no longer working - tllim - 03-09-2016

(03-09-2016, 02:45 PM)peterz Wrote:
(03-09-2016, 01:36 PM)tllim Wrote:
(03-09-2016, 12:09 PM)janjwerner Wrote: Have you tried the UART pins on the EXP port? I guess everything is wired to same place, but maybe there is some issue with a a connector.

Better use EXP port for UART console cable. The Euler port UART pin has voltage shifter and Euler port do not.

According pinout there is possible to have 6 UARTS (I plan to test this once I have my PINE64 in hands together with modules based on MAX3232 chip from ebay).
https://drive.google.com/a/pine64.com/file/d/0B0cEs0lxTtL3YU1CNmJ2bEIzTlE/view?usp=sharing

1 of UARTs is on PI bus. I'd try this.
pin6 - GND
pin8 - UART_TXD
pin10 - UART_RXD

But don't know what device file each UART will have.
Try check what device files are there containing "tty" under /dev .

Combine both Euler and Pi2 bus, the maximum available UART is 4.

RE: USB TTL cable no longer working - peterz - 03-09-2016

[quote pid='3287' dateline='1457557488']
Combine both Euler and Pi2 bus, the maximum available UART is 4.
[/quote]

There is also EXP bus and Wifi/BT Connector (J50). I suppose those would work as well (I won't use wifi/BT modul).

RE: USB TTL cable no longer working - tllim - 03-09-2016

(03-09-2016, 03:09 PM)peterz Wrote: [quote pid='3287' dateline='1457557488']
Combine both Euler and Pi2 bus, the maximum available UART is 4.

There is also EXP bus and Wifi/BT Connector (J50). I suppose those would work as well (I won't use wifi/BT modul).
[/quote]

You plan to max out all UART ports :-)

RE: USB TTL cable no longer working - taros - 03-09-2016

Thanks for the replies.

I use Ubuntu and the appropriate devices are autocreated in /dev/. The default is /dev/ttyUSB0.
I tried two different UART cables, both with the following characteristics,

Code:
[46297.049241] usb 1-9: new full-speed USB device number 4 using xhci_hcd

[46297.178108] usb 1-9: New USB device found, idVendor=067b, idProduct=2303

[46297.178116] usb 1-9: New USB device strings: Mfr=1, Product=2, SerialNumber=0

[46297.178121] usb 1-9: Product: USB-Serial Controller

[46297.178124] usb 1-9: Manufacturer: Prolific Technology Inc.

[46298.217991] usbcore: registered new interface driver usbserial

[46298.218005] usbcore: registered new interface driver usbserial_generic

[46298.218015] usbserial: USB Serial support registered for generic

[46298.219383] usbcore: registered new interface driver pl2303

[46298.219397] usbserial: USB Serial support registered for pl2303

[46298.219411] pl2303 1-9:1.0: pl2303 converter detected

[46298.220266] usb 1-9: pl2303 converter now attached to ttyUSB0

I tried both the PINs 6/8/10 (GND, TX, RX) on the Euler connector and also PINs 6/7/8 (GND, TX, RX) on the Exp connector.
I did not get any response at speed 115200.
I cannot figure out what changed so that now I do not get any output from the serial cable.
If a solution is found, I will document the whole process on the wiki!

RE: USB TTL cable no longer working - longsleep - 03-09-2016

I dont know anything but try to switch rx and tx?

RE: USB TTL cable no longer working - tllim - 03-09-2016

(03-09-2016, 04:40 PM)longsleep Wrote: I dont know anything but try to switch rx and tx?

My suggestion same as longsleep.