amc1.5 connection problem

Hi,

I have managed to finish the amc1.5 and h-bridge1.2b. All works fine...

But now I'm trying to enter the hyper terminal.
I'm running vista 64-bit and have installed hyperterminal 6.3 from hillgraeve.

Had some trouble opening comports but now it says connected.
Although nothing is happening. No text is appearing in the window.

I'm using the 22mhz crystal with firmware v1.0. When I set dipswitch 2 to on
the amc does not display hyperterminal mode on the lcd.

What can be the problem?

gr. Jeroen

If the window from the Hyper terminal is open, set dipswitch 2 to on and reset the AMC-Board with the resetbutton or plugoff and plugin the power supply, after that you should see the text in the window. Does it work now?.
Do you see other things on the LCD Display?.

Hi michael,

No it does not. The lcd display the potmeter values and 22PWM v1.0 SFGT.

gr Jeroen

Hmm strange :? . Do the dipswitch works correctly?, and do you have set the 3 jumpers (over the dipswitch) onto the board like in the picture?.
I think or hope Thanos will have an answer.

Hi Jeroen,

Have you attached cables to both RX and TX ports? This is required for the two-way communication with hyperterminal.

Also try to set the flow control to NONE in the hyperterminal settings.

What worries me is that you didn't received the message AMC1.5 setup KP , TIP:use Terminal on the lcd screen. Perhaps the pull-up resistors are not in place? Can you post a photo of the board please? It would help to clarify these issues better.


Thanos

Hi Thanos,

Tried all those things and the cables are connected. In an earlier stage I did get the
tip-hyperterminal on the lcd.

Jeroen, please make a photo from the AMC Board too.

Hi,

Sorry I do not have an highres camera...

The problems with the atmega are starting all over again. The error
'device missing' is haunting me again. Don't know what the problems
are anymore. So this means that there is seriously something wrong
with the board and I don't know what. I have checked it so many
times that the fun is almost over.

gr. Jeroen

Hi Jeroen,

I noticed that you are using LCD with blue backlight. These LCD's don't work with backlight OFF...

The backlight draws a significant amount of current from the LM2940 regulator making it hot. I have left my setup with this blue LCD (backlight ON) for about an hour and the regulator was very hot even if I had used on it heatsink. Guess what. I could not either connect to the hyperterminal either after that.

I can suggest to use a higher resistor on the LCD board perhaps 20 or 50 ohm...

OR use a piece of wire to connect the middle pin of the jumper switch for the backlight with the input pin of the LM2940 that exists on the AMC1.5 board!! This will give pure amps to the backlight directly from your power supply bypassing the LM2940!!!! Be aware that the input voltage not be more that 9volts or you may overheat the LCD leds!!!! See these photos:





Also noticed that you cannot operate them without the backlight ON. You can't see anything otherwise. On my existing board design the contrast pin is grounded for the maximum contrast, that works well on normal green LCD's but not on these ones!!! So I decided to add a potentiometer to control their contrast as well. I had to cut the traces around pin 3 of the LCD and solder a wire that goes to the center pin of a potentiometer (wiper), I had marked that wire with orange color on my photos. The rest two cables of the potentiometer goes to ground and to +5v.






I hope this helps out.



Regards, Thanos

Hey, you could use something like this:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=270340530619

Among its application uses: Industries produce viewing e.g. PCB\Electronic components inspection :brows:


Regards, Thanos

Hi Thanos,

Thanks for the info about the lcd. You are right. The regulator was getting very hot and I could not read the lcd very good, only on an angle.
So thats the problem... will do it your way. The only thing is that I get the power for the cooler from the amc, which runs on 12v.

And I think I found the problem with connecting. Found out that I was using the 22mhz crystal with the 22pf(?). Now I have soldered the 18mhz
crystal and now it programming...

Hope it works all out now.

gr. Jeroen

Hi Jeroen

If you are using 12V as power supply to power the AMC, and going to use the piece of wire fix, you must change the 10 ohm resistor on the LCD board with a 20 ohm or higher to avoid overheating the LCD backlight leds!!!

Generally its better to power the AMC with power supply that provides 6V to 9V. With 12V the LM2940 might overheat even without the LCD connected!

Also be sure that the crystal you have is not just 18Mhz but exactly 18.432Mhz (18.432.000 Hz) . And use the firmware that works for this crystal.

Regards ,Thanos

Hi,

I just programmed the 18.432mhz firmware. No problems at all...
Connected a wire between the LM and LCD. So far so good.
And 6 volt input.

But... still no hyperterminal. The converter is connected on
com1. That is working fine. Hyperterminal says connected
but nothing is happening.

gr. Jeroen

Show us a pic, where we can see how you have wired the RX TX connectors. And put a lamp pointing to the board, while taking the picture.

You said the magic word... Converter. If this is a USB converter based on FTDI, you can go to the COM port settings and enable the Serial Printer option.

I had to do the serial printer option on my Digitus USB2Serial converters to be able to get hyperterminal to work. Otherwise the hyperterminal just sits waiting to autodetect the baud rate!

Ego is right. A photo would help us to see if something is wrong with your cabling as well.

Regards Thanos

Hi,

Excuse me for the dumb question... but where can I
find the serial printer option? You mean in windows?

Sorry for the pics, can't get them any better.

gr. Jeroen

Yes its in your computer device setting:



--> System properties
--> Device manager
--> USB Serial Port (COM5) (or COM1...)
--> USB Serial Port (COM5) Properties
--> Advanced
--> Serial Printer box (place a tick)


Thanos

Hi Thanos,

There is no such option or window in my vista x64...
In the advanced window the only thing I can change is the comport itself.

And on my other computer which runs on xp its the same.

gr. Jeroen

What USB to serial converter you are using then? Any link of it?

I use these: http://www.digitus.info/en/products/accessories/?c=1216&p=3530

EDIT: I seen it on your photo... You are using prolific USB to Serial ... :? Not good...


Thanos

Jeroen, sorry but you have to buy a FTDI based USB2Serial converter...

I have never used Prolific USB2serial converters, and not heard of anyone got them work with my electronics.

If you read the SCN5 threads too, you will see that all USB-2-RS485 converters they use are based on FTDI chipset... :


Regards, Thanos