USB Serial cable programming grief !

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Tim036

Member
I'm new to this Forum but have used non Picaxe systems.

Looks brilliant but I'[ve fallen at the first hurdle.

I've got the Dev board with a 18X chip in it.

I've got the dUSB divers onto the laptop running XP

I go to options selecting COM5 on the serial page and rub the 'test'

using the LED for testing for 0v to +5v

Now it gives 0V and 2.32 Volts ...

Gulp !

What next ?

Needless to say its does not programme in the test program just loads of error messages...

Any thoughts very very welcome as this is Day zero for me !

:confused::confused::confused:

Tim
 
Technical

Technical

Technical Support
Staff member
What power supply are you using - and where is it connected? What is the actual multimeter voltage reading across V+ and 0V (ie the spare pins below the 18X).

Which type of USB cable?
 
T

Tim036

Member
Technical said:
What power supply are you using - and where is it connected? What is the actual multimeter voltage reading across V+ and 0V (ie the spare pins below the 18X).

Which type of USB cable?
Click to expand...
Its a 9v power supply through the on board 7805 regulator yielding +5v across Pic IC pin 5 and 14

Its in the middle serial socket on the side of the board against the factory fitted 18X IC

The cable is an AXE026

Mant thanks for the response.

:):)

Tim
 
T

Tim036

Member
T

Tim036

Member
kewakl said:
see http://www.picaxeforum.co.uk/showthread.php?t=12579&highlight=solder+bridge
Click to expand...
Many thanks for the link.

I've checked the 22k 10k and reset switch and the 4.7k resistor.

All aok !

I've also swapped the 18X IC

Now the voltage out of the USB cable is 2.38 ! but not detectable on the 3.5mm stereo plug when not plugged into the board !

When the reset pin is pressed the voltage on pin 3 of the 18X goes from 2.32 to 2.07, when the 'TEST' led in the software is on.

Clutching at straws:-

Is the data strobing from the USB cable 50:50 mark space ratio ?

Are the drivers duff install for the usb cable ? The ones I used came off the CD.

I have a usb to rs232C adaptor so I could use the 9 way serial cable and i know the adaptor works ?

An help is very very welcome 1

:):):)

Tim
 
B

BeanieBots

Moderator
Tim036 said:
When the reset pin is pressed the voltage on pin 3 of the 18X goes from 2.32 to 2.07, when the 'TEST' led in the software is on.
Click to expand...
This sounds like a power supply problem.
With the 9 way 'D' connector towards you:- (and the board powered)
Put your DVM 0v lead on the power in block left hand pin.
1. What is the voltage on the regulator pin nearest the proto-area?
2. What is the voltage on the middle pin?
3. What is the voltage on the pin furthest from you?
4. What is the voltage on leg 5 of the 18X?
5. What is the voltage on leg 14 of the 18X?
 
hippy

hippy

Ex-Staff (retired)
Tim036 said:
Are the drivers duff install for the usb cable ? The ones I used came off the CD.
Click to expand...
Which download cable are you using ? You said previously you were using an AXE026 cable which is non-USB.

If you have an AXE026 connected via a USB010 USB-to-Serial adapter the drivers are available for download via the "Software and Drivers" link at the top of the forum page.
 
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T

Tim036

Member
I have a rock solid +5 volts acrodd the IC so I do not believe the psu is a problem.

Its an AX 027. I picked the wong platic bag to get the part number, sorry.

:)

Tim
 
T

Tim036

Member
hippy said:
Which download cable are you using ? You said previously you were using an AXE026 cable which is non-USB.

If you have an AXE026 connected via a USB010 USB-to-Serial adapter the drivers are available for download via the "Software and Drivers" link at the top of the forum page.
Click to expand...

Does a serial cable need drivers ?

My USB to RS232C thing already has working drivers.

:)

Tim
 
S

SilentScreamer

Senior Member
If you have the AXE027 you don't need a USB to RS232 converter? Which cable from the below two do you have? Is it a "proper" rev-ed cable?



 
D

Dippy

Moderator
No, a purely serial cable doesn't need (extra) drivers.
Lets fort that for now.

Looks like confusion is setting in already.
Let's clarify before people go up some random garden path.

You have:-
1 x AXE091 Dev board with an 18X inserted
1 x AXE027 USB-Serial PICAXE cable
Installed the USB drivers from Rev-Ed site correctly.
Powered up the Dev board correctly
And checked the voltages at the 18X +v and 0V (gnd) pins.

Is that right?

Can you check voltages directly at jack? (see the AXE091 Data Sheet to see the connections)
I guess you haven't got an oscilloscope?
 
hippy

hippy

Ex-Staff (retired)
Tim036 said:
Does a serial cable need drivers ?

My USB to RS232C thing already has working drivers.
Click to expand...
No, a hardware serial cable (AXE026) does not need drivers, it simply plugs into a 9-way D on the back of a PC, usually appears as COM1 through COM4, and that's it; select the COM port and download.

If an AXE026 is plugged into a USB-to-serial adpater then the USB-to-serial adapter will need to have a driver.

An AXE027 is an integrated USB-to-serial download cable which does not need any other USB-to-serial adapter but does require the correct USB driver.

You have a problem downloading so we need to isolate what that may be, thus we need to know exactly what cable, cables, and/or USB-to-Serial adpaters are being used - AXE027, USB010 plus AXE026 or some other combination.

Tim036 said:
My USB to RS232C thing already has working drivers.
Click to expand...
It is not clear what this "USB to RS232 thing" is. Concise and clear information will help everyone in resolving the problem you are having.

Tim036 said:
I have a usb to rs232C adaptor so I could use the 9 way serial cable and i know the adaptor works ?
Click to expand...
If you cannot get the AXE027 to work ( which is what it appears you are ultimately trying to get working ) then you can try with a USB-to-Serial adapter plus an AXE026 cable. Whether this USB-to-serial adapter will work for PICAXE downloading depends upon what the adapter is. If it's a USB010 then it should work providing the correct USB drivers are installed. If it's not a USB010 then it may not work for PICAXE downloading and simply confuse matters further.

You can also try with an AXE026 connected to a physical COM port if your PC has one.


If you are wanting to utimately use an AXE027 then it would be best to concentrate on trying to get that to work.

With the AXE027 cable disconnected from the AXE091 development board, with a DVM ( black probe to 3.5mm jack tip and red probe to 3.5mm jack ring ), using the Serial Port test, what voltages do you see ?
 
T

Tim036

Member
Dippy said:
No, a purely serial cable doesn't need (extra) drivers.
Lets fort that for now.

Looks like confusion is setting in already.
Let's clarify before people go up some random garden path.

You have:-
1 x AXE091 Dev board with an 18X inserted
1 x AXE027 USB-Serial PICAXE cable
Installed the USB drivers from Rev-Ed site correctly.
Powered up the Dev board correctly
And checked the voltages at the 18X +v and 0V (gnd) pins.

Is that right?

Can you check voltages directly at jack? (see the AXE091 Data Sheet to see the connections)
I guess you haven't got an oscilloscope?
Click to expand...
Spot on right on all inc Scope.

The jack is a mystery the tip is 0v and the middle band data going to the 18x

I can't measure any voltage across them but the pic does react to the 'TEST' led in the software!

Maybe I should try that again ? what should i find ?

with the 3.5mm plug out of the dev board socket.

:)

Tim
 
S

SilentScreamer

Senior Member
Tim036 said:
I can't measure any voltage across them but the pic does react to the 'TEST' led in the software!
Click to expand...
How do you mean the PIC responds? The LED simply changes the state of the data line?

Do you have a multimeter? If so put it with the black lead on the tip of the jack and the red lead on the middle. When the LED in the serial port test is on it should read a positive voltage. When the LED is off it should read 0V or below.
 
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B

BeanieBots

Moderator
With your DVM 0v probe on the AXE027 tip, and the +ve probe on the ring nearest the tip, what voltages do you see when you do the LED test. (lead NOT plugged into dev board)
LED = black voltage = ?
LED = green voltage = ?
 
D

Dippy

Moderator
Can you measue any activity on jack with 'scope? (either when trying a download, or if simply fiing something out using terminal).

Do you have access to a PC with a genuine RS232 plug-hole? (assuming you have a serial download cable of course! )

Do you have another 18X? (Please tell me you bought more than one...;) )

We need to nail which part is dicky. Drivers/AXE027/Dev-Board/PC/PICAXE.

I assume you've checked Windows/Device Manager Ports an USB Controllers to make sure everything is installed and (cough,cough) "working crrectly"?
 
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hippy

hippy

Ex-Staff (retired)
Tim036 said:
The jack is a mystery the tip is 0v and the middle band data going to the 18x

I can't measure any voltage across them but the pic does react to the 'TEST' led in the software!

Maybe I should try that again ? what should i find ?
Click to expand...
With the correct COM port select in View->Options, when Serial Test is executed and the on-screen LED is clicked, you should be reading near to 0V when the on-screen LED is off, and near to +5V when the on-screen LED is on.

If the PICAXE reacts to clicking the on-screen LED there should be a measurable voltage across tip and ring. In what way does the PICAXE react to the on-screen test LED ?
 
T

Tim036

Member
Dippy said:
Can you measue any activity on jack with 'scope? (either when trying a download, or if simply fiing something out using terminal).

Do you have access to a PC with a genuine RS232 plug-hole? (assuming you have a serial download cable of course! )

Do you have another 18X? (Please tell me you bought more than one...;) )

We need to nail which part is dicky. Drivers/AXE027/Dev-Board/PC/PICAXE.

I assume you've checked Windows/Device Manager Ports an USB Controllers to make sure everything is installed and (cough,cough) "working crrectly"?
Click to expand...
Spot on.Yes I bought 2 extra and already swapped with not result.

Measurements yield 0 ! Like the lead was faulty ! I can only re-measure tonight.

:)

Tim
 
T

Tim036

Member
hippy said:
With the correct COM port select in View->Options, when Serial Test is executed and the on-screen LED is clicked, you should be reading near to 0V when the on-screen LED is off, and near to +5V when the on-screen LED is on.

If the PICAXE reacts to clicking the on-screen LED there should be a measurable voltage across tip and ring. In what way does the PICAXE react to the on-screen test LED ?
Click to expand...
Cannot re-confirm that until tonight...

:(

Tim
 
G

gengis

New Member
I had a chip that wouldn't program at 3 volts, but worked fine at 4.5 volts - and still worked at 3 volts after programming.

The actual voltage you see on the pin will change with the power supply voltage to the chip. I see ~2.3 2.4 when running 3 volts a little higher at 4.5 volts.

I worked from the book and got receive and transmit backwards - R&T are dependent on one's point of view. Make sure the correct IC pin is toggling and make sure the output pin is connected properly and not loaded down too much.

Beyond that, your communication baud rate has to be correct
 
T

Tim036

Member
Flooby said:
I had a chip that wouldn't program at 3 volts, but worked fine at 4.5 volts - and still worked at 3 volts after programming.

The actual voltage you see on the pin will change with the power supply voltage to the chip. I see ~2.3 2.4 when running 3 volts a little higher at 4.5 volts.

I worked from the book and got receive and transmit backwards - R&T are dependent on one's point of view. Make sure the correct IC pin is toggling and make sure the output pin is connected properly and not loaded down too much.

Beyond that, your communication baud rate has to be correct
Click to expand...
Baud rate on a USB AIX027 cable.

How do I adjust that ?

: )

Tim
 
T

Tim036

Member
I have just confirmed all my previous observations including no significant voltage swing between the usb cable aix027 when subject to the led 'Test'.

But when 18X is in the dev board it swings between -0.09v and 2.38 on thes usb side and 2.32 vikts on pon 3 of the chip with 5v on the chip.

Trying out a RS232C cable Aix026

Totally stumped here.....

:confused::confused::confused::confused:

Tim
 
T

Tim036

Member
Tim036 said:
I have just confirmed all my previous observations including no significant voltage swing between the usb cable aix027 when subject to the led 'Test'.

But when 18X is in the dev board it swings between -0.09v and 2.38 on thes usb side and 2.32 vikts on pon 3 of the chip with 5v on the chip.

Trying out a RS232C cable Aix026

Totally stumped here.....

:confused::confused::confused::confused:

Tim
Click to expand...
The RS232C cable AIX026 worked a treat !

So I guess the usb cable is going back for test and replacement !

What can we learn from this ?

Tim
 
slimplynth

slimplynth

Senior Member
Tim036 said:
The RS232C cable AIX026 worked a treat !

So I guess the usb cable is going back for test and replacement !

What can we learn from this ?

Tim
Click to expand...
Not sure Tim... It's still a mystery. I can honestly say I've never had a problem with my AXE027.
 
Technical

Technical

Technical Support
Staff member
Quote from a PM,

Tim036 said:
Hi,
It was recently loaned to me by L** T*** who recommended me to get the same kit he has. Does he have to send it to you or can I seeing how I bought the Dev kit off you last week?:) Tim Moore
Click to expand...
Perhaps next time before lots of people spend their time assisting on the forum you could check with your friend if the cable was working when he lent it - a second hand borrowed cable not working is not the same as a new off-the-shelf cable not working...
 
T

Tim036

Member
slimplynth said:
Not sure Tim... It's still a mystery. I can honestly say I've never had a problem with my AXE027.
Click to expand...


Had me guessing a lot !

Many many thanks to al those members who posted and supported me during this trauma ridden start to my PicAxe experience.

I knew it to be an elegant well documented development system, but if your data won't go in the chip ?

Most frustrating !

Thanks again to the members of this Forum - a happy for now !

:D:):D:)

Tim
 
T

Tim036

Member
Technical said:
Quote from a PM,



Perhaps next time before lots of people spend their time assisting on the forum you could check with your friend if the cable was working when he lent it - a second hand borrowed cable not working is not the same as a new off-the-shelf cable not working...
Click to expand...

New factory seal that I broke open myself.

totally agree with your comment "a second hand borrowed cable not working is not the same as a new off-the-shelf cable not working.."

Tim
 
E

eclectic

Moderator
Tim036 said:
The RS232C cable AIX026 worked a treat !

So I guess the usb cable is going back for test and replacement !

What can we learn from this ?

Tim
Click to expand...
Based on a small sample,
and just my experiences.

I own two AXE027 cables, which are used
between three computers.

The first one "didn't work".
So, I re-read the instructions, thoroughly, including

the COM port settings/
plugging in the cable FIRST/
using the same USB port.

and all the rest of the installation instructions.

And then it started to work!

And the second one behaved itself, first time.

Again, this is just my experience.

e
 
T

Tim036

Member
eclectic said:
Based on a small sample,
and just my experiences.

I own two AXE027 cables, which are used
between three computers.

The first one "didn't work".
So, I re-read the instructions, thoroughly, including

the COM port settings/
plugging in the cable FIRST/
using the same USB port.

and all the rest of the installation instructions.

And then it started to work!

And the second one behaved itself, first time.

Again, this is just my experience.

e
Click to expand...
Maybe I ought to test it once more but if the voltage does not twitch on the tip of the connector then some thing up stream of it does not work correctly or is setup wrong.


Finger trouble first time on using a new system is the rule ! *LOL*

:)

Tim
 
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Technical

Technical

Technical Support
Staff member
Tim036 said:
Maybe I ought to test it once more but if the voltage does not twitch on the tip of the connector
Click to expand...
That could be a broken cable, but is more likely to be a driver incorrectly setup. What do you see in Device Manager under Ports (COM & LPT)?
 
hippy

hippy

Ex-Staff (retired)
Tim036 said:
Maybe I ought to test it once more but if the voltage does not twitch on the tip of the connector then some thing up stream of it does not work correctly or is setup wrong.
Click to expand...
In Post #1 you reported "it gives 0V and 2.32 Volts", and you also reported the PICAXE reacting to the Serial Test, though you could not see any voltage change of the signal. So it appears that something was working to some extent.

I'd suggest double-checking your DVM is working as it should be, un-install the USB drivers and install those from the Rev-Ed web site and test again.
 
T

Tim036

Member
hippy said:
In Post #1 you reported "it gives 0V and 2.32 Volts", and you also reported the PICAXE reacting to the Serial Test, though you could not see any voltage change of the signal. So it appears that something was working to some extent.

I'd suggest double-checking your DVM is working as it should be, un-install the USB drivers and install those from the Rev-Ed web site and test again.
Click to expand...

I did that and also changed to a DVM which is super accurate. It indicated there was 375mV of varying signal on the usb cable. But didn't change with the LED test.

I tried to reinstall the driver as suggested but XP refused to do it as it said the downloaded drivers were no better than the ones in there !

Perhaps I should have uninstalled it and re-installed it.

I've sent it away for testing now as the RS232C port works.

I confess to being mystified by what I saw especially as the AIX026 cable worked fine out of the bag !

Many thanks for your support.

:)

Tim
 
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T

Tim036

Member
Technical said:
That could be a broken cable, but is more likely to be a driver incorrectly setup. What do you see in Device Manager under Ports (COM & LPT)?
Click to expand...

From memory:-

AIX027 (COM5)

and on right clicking on it and selecting properties XP thought it was working OK.

I've sent the AIX027 cable off to a colleague who recommended this Pic development system to me, for testing.

I can now start writing code !

I would like to think it was a driver problem but in a few days we will know for sure if it was that or a dead cable.

As I can move on from this an concentrate on the syntax of this version of Basic, I'm now a happy user !


Appreciate your responses.

:)

Tim
 
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T

Tim036

Member
Tim036 said:
I did that and also changed to a DVM which is super accurate. It indicated there was 375mV of varying signal on the usb cable. But didn't change with the LED test.

I tried to reinstall the driver as suggested but XP refused to do it as it said the downloaded drivers were no better than the ones in there !

Perhaps I should have uninstalled it and re-installed it.

I've sent it away for testing now as the RS232C port works.

I confess to being mystified by what I saw especially as the AIX026 cable worked fine out of the bag !

Many thanks for your support.

:)

Tim
Click to expand...
For all those members who folled this thread and to those who contributed:-

It was swapped out on a working system using a AIX027 USB CABLE and it was dead as a door nail, as in DOA , so it was probably in that state in its factory sealed bag.

It can happen, but likely very very rare.

What can we learn ?

a) Members of this Forum don't give up easy !

b) Massive plus if you have access to an existing working system !

c) Lightning does strike but its very very rare.

Thanks to every one who posted. I learnt loads about this Dev environment !

I grew to really appreciate that LED Test facility ! A master stroke including it in a very elegant system !

Thanks again.

A happy !

;);)

Tim
 
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L

Lez T

Member
Just received the cable back from Tim, tested it in my dev kit, it does not work. Retested my original cable no problems, second test of cable I gave to Tim and still not working, retest mine again and it's ok. I think that we can say that it's defective.
Technical, any procedure to do to return for a new one?
Lez.

Both cables were bought at the same time and are Axe027 USB cables
 
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