Not able to type on serial console conncted rasberry PI

[manishg]

I have recently purchased the rasberry pi started kit.

Have installed the whezzy rasbian and trying to connect through serial console. I can see the OS is booting up and it shows me the login screen. But i cannot enter any character or command from the laptop keyboard. I tried using the external keyboard but still the same issue.

See the attached cosole.jpg which shows the os is booted up and login screen is present but i cannot type any command here.

Let me know what i am missing here ?

Thanks,
Manish

[joan]

What connections have you made between the Pi and PC? How? What software are you running on the PC?

[manishg]

I am using windows machine and installed the com driver. PI is connected through USB Micro-B Cable for powering.

and black, green and white wires to the GPIO header using TTL cable

I am using putty to connect to PI, it shows the booting sequence but keyboard doesn't work. Shall i use the external adaptar for powering the device.

Thanks,

[joan]

I am using windows machine and installed the com driver. PI is connected through USB Micro-B Cable for powering.

and black, green and white wires to the GPIO header using TTL cable

I am using putty to connect to PI, it shows the booting sequence but keyboard doesn't work. Shall i use the external adaptar for powering the device.

Thanks,

To help we need to know the model of serial dongle you are using and the connections you have made between the Pi and dongle. I have no idea what the black, green, and white wires are connected between.

[FTrevorGowen]

I am using windows machine and installed the com driver. PI is connected through USB Micro-B Cable for powering.
and black, green and white wires to the GPIO header using TTL cable
I am using putty to connect to PI, it shows the booting sequence but keyboard doesn't work. Shall i use the external adaptar for powering the device.
Thanks,

To help we need to know the model of serial dongle you are using and the connections you have made between the Pi and dongle. I have no idea what the black, green, and white wires are connected between.

+1
If you can, post a picture or link. FWIW, take a look at what I've done here:
http://www.cpmspectrepi.webspace.virgin ... pters.html
To check the keyboard independently of the Pi perform a loopback test** (as shown - in your case with hyperterminal since you're Windows based). Also, whilst doing that, double-check that the device is producing 3.3V signal levels, not 5V.
Trev.
** connect the device's Tx lead back to it's Rx lead

[manishg]

I am using windows machine and installed the com driver. PI is connected through USB Micro-B Cable for powering.

and black, green and white wires to the GPIO header using TTL cable

I am using putty to connect to PI, it shows the booting sequence but keyboard doesn't work. Shall i use the external adaptar for powering the device.

Thanks,

To help we need to know the model of serial dongle you are using and the connections you have made between the Pi and dongle. I have no idea what the black, green, and white wires are connected between.

I have purchased the Raspberry Pi Starter Pack from adafruit website.(http://www.adafruit.com/products/1014)
It contains
> Raspberry Pi Model B 512MB RAM
> 3' long USB Micro-B Cable -
> 5V 1A power adapter -
> USB TTL console cable (http://www.adafruit.com/products/954)-
>SD Card 4GB size
I did the connection mentioned @https://learn.adafruit.com/adafruits-ra ... gpio-setup

Used the putty software on windows to serial connect the pi, it showed me the OS is booting but i am not able to type anything on the login prompt (see in the attached image)

Let me know what other info you need to debug the problem.

Thanks

[joan]

Last attempt.

What connections have you made between the Pi and the dongle?

[manishg]

Last attempt.

What connections have you made between the Pi and the dongle?

I have USB to TTL Serial Cable (see image http://www.adafruit.com/products/954), it has four wires (red, black, green, white)

I have connected the pi using this cable through USB port of my laptop as follows

The red lead is connected to 5V pin of PI,
The black lead to GND PIN ,
The white lead to TXD PIN.
The green lead to RXD PIN

see the following image for exact connection.
https://learn.adafruit.com/adafruits-ra ... t-the-lead

Let me know if it helps

[joan]

That looks OK.

Are you powering through the microUSB? If so don't connect the power lead from the dongle.

I can't see this been a baud rate problem as both ends will normally be set to the same rate for TX and RX. It should just work in both directions.

[manishg]

That looks OK.

Are you powering through the microUSB? If so don't connect the power lead from the dongle.

I can't see this been a baud rate problem as both ends will normally be set to the same rate for TX and RX. It should just work in both directions.

I tired with both ways, first without powering through microUSB
and secondaly with microUSB and removing the lead from dongle,
with both the options, problem is still there.

[mahjongg]

perhaps its a hardware handshake problem?
disable handshaking in your windows comms program.
connect rx and tx of the USB dongle together, and see if your typed characters are echoed.

[FTrevorGowen]

perhaps its a hardware handshake problem?
disable handshaking in your windows comms program.
connect rx and tx of the USB dongle together, and see if your typed characters are echoed.

+1
(This is what I referred to as a "loopback test" in my previous post, although I forgot to mention "handshaking" )
Trev.

[manishg]

perhaps its a hardware handshake problem?
disable handshaking in your windows comms program.
connect rx and tx of the USB dongle together, and see if your typed characters are echoed.

Will check and update you ASAP

[manishg]

Now i have started getting the following errors on the screen. (No login prompt)

[ 87.033419] SysRq : HELP : loglevel(0-9) reboot(b) crash(c) terminate-all-tasks(e) memory-full-oom-kill(f) debug(g) kill-all-tasks(i) thaw-filesystems(j) sak(k) show-memory-usage(m) nice-all-RT-tasks(n) poweroff(o) show-registers(p) show-all-timers(q) unraw(r) sync(s) show-task-states(t) unmount(u) show-blocked-tasks(w)

I am using 4GB SD card with wheezy-raspbian loaded. Have formated the card and reloaded the OS again but it keeps on crashing.

Thanks

[joan]

You are getting some symptoms associated with a poor power supply. If you have a meter it would be worth checking the voltage between TP1 and TP2 on the Pi. It should be 5 volts.

[AndrewS]

[ 87.033419] SysRq : HELP : loglevel(0-9) reboot(b) crash(c) terminate-all-tasks(e) memory-full-oom-kill(f) debug(g) kill-all-tasks(i) thaw-filesystems(j) sak(k) show-memory-usage(m) nice-all-RT-tasks(n) poweroff(o) show-registers(p) show-all-timers(q) unraw(r) sync(s) show-task-states(t) unmount(u) show-blocked-tasks(w)

I think that can also be caused if your PC is sending "garbage" characters to the Pi's serial port - the Pi sees them as valid debugging commands, and then goes "strange"
Double check the COM Port settings on the PC side.

[manishg]

[ 87.033419] SysRq : HELP : loglevel(0-9) reboot(b) crash(c) terminate-all-tasks(e) memory-full-oom-kill(f) debug(g) kill-all-tasks(i) thaw-filesystems(j) sak(k) show-memory-usage(m) nice-all-RT-tasks(n) poweroff(o) show-registers(p) show-all-timers(q) unraw(r) sync(s) show-task-states(t) unmount(u) show-blocked-tasks(w)

I think that can also be caused if your PC is sending "garbage" characters to the Pi's serial port - the Pi sees them as valid debugging commands, and then goes "strange"
Double check the COM Port settings on the PC side.

my com port settings are as follows:
baud=115200
Data Bits=8
stop bits=1
parity=None
Flow Control=None

I tried joining the tx and rx and was able to see the characters what i was sending.

[manishg]

You are getting some symptoms associated with a poor power supply. If you have a meter it would be worth checking the voltage between TP1 and TP2 on the Pi. It should be 5 volts.

will check the voltage

[AndrewS]

There's a similar-sounding problem here where it turns out the problem was actually a physically damaged RX pin on the Pi

[manishg]

Untitled.gif (36.62 KiB) Viewed 7121 times

Untitled.gif (36.62 KiB) Viewed 7121 times

Untitled.gif (36.62 KiB) Viewed 7121 times

You are getting some symptoms associated with a poor power supply. If you have a meter it would be worth checking the voltage between TP1 and TP2 on the Pi. It should be 5 volts.

I checked and it was 5 volts.
I tried with the usb internal power source (attaching red wire to th pi board) . I was able to login but suddenly the crash messages coming in (see the attached image). I have also double check the com port setting and PC is not sending the garbage character to the particular com port. Is something woring with board itself ?

[AndrewS]

Still got no idea what's causing your problem, but http://tldp.org/HOWTO/Remote-Serial-Con ... sysrq.html suggests a couple of ways of disabling the SysRq key, which is what your images appear to be showing.