Comments on: Building a Wifi Radio – Part 7, Building an LCD Display http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/ Join the resistance. Fri, 12 Mar 2010 10:16:27 -0800 http://wordpress.org/?v=2.9.2 hourly 1 By: Jeff http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3931 Jeff Tue, 28 Apr 2009 08:06:28 +0000 http://mightyohm.com/blog/?p=822#comment-3931 Glad to help! :-) Glad to help! :-)

]]> By: Chris http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3929 Chris Tue, 28 Apr 2009 06:23:38 +0000 http://mightyohm.com/blog/?p=822#comment-3929 Thanks for the super fast response :D Thanks for the super fast response :D

]]> By: Jeff http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3928 Jeff Tue, 28 Apr 2009 05:42:31 +0000 http://mightyohm.com/blog/?p=822#comment-3928 Chris, The WL-520gU has a 3.3V serial port. I am running the AVR at 5V. The AVR can handle a 3.3V serial input with no problem so I connected that directly. On the TX side, however, you need to limit the voltage to avoid going above 3.3V and potentially damaging the router. In part 8 I used a resistor divider made of two 1k resistors to do this - ideally it will limit the voltage to 2.5V. It may also slow down the serial pulse edges but I haven't seen any problems in my testing. Jeff Chris,

The WL-520gU has a 3.3V serial port. I am running the AVR at 5V. The AVR can handle a 3.3V serial input with no problem so I connected that directly. On the TX side, however, you need to limit the voltage to avoid going above 3.3V and potentially damaging the router. In part 8 I used a resistor divider made of two 1k resistors to do this – ideally it will limit the voltage to 2.5V. It may also slow down the serial pulse edges but I haven’t seen any problems in my testing.

Jeff

]]> By: Chris http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3926 Chris Tue, 28 Apr 2009 05:20:06 +0000 http://mightyohm.com/blog/?p=822#comment-3926 Hey Jeff I almost asked this in the forum, but thought it maybe easier to ask here as other maybe thinking the same thing in relation to the circuit diagram. I see that you have RX -> TX connected from the 520 to the ATmega, but aren't they running at different voltages? I realize the Voltage line out on the serial port on the 520 isn't connected to anything, and I'm assuming the ATmega is running at 5V. Is that the case? I'm currently connecting my 520 to an Arduino, via the USB port on the Arduino to a USB Serial on the 520, but that's not looking like it'll work reliably, so I'm back to using the internal on board serial on the 520, or maybe moving over to a 500GP. Thanks Chris Hey Jeff

I almost asked this in the forum, but thought it maybe easier to ask here as other maybe thinking the same thing in relation to the circuit diagram.

I see that you have RX -> TX connected from the 520 to the ATmega, but aren’t they running at different voltages? I realize the Voltage line out on the serial port on the 520 isn’t connected to anything, and I’m assuming the ATmega is running at 5V. Is that the case?

I’m currently connecting my 520 to an Arduino, via the USB port on the Arduino to a USB Serial on the 520, but that’s not looking like it’ll work reliably, so I’m back to using the internal on board serial on the 520, or maybe moving over to a 500GP.

Thanks
Chris

]]> By: Jeff http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3653 Jeff Sat, 04 Apr 2009 18:38:48 +0000 http://mightyohm.com/blog/?p=822#comment-3653 Hey Foo, First of all, I created a new forum for this project over at http://mightyohm.com/forum/viewforum.php?f=2 to help facilitate discussions like these. I know using the blog comment area exclusively for support was starting to get on some people's nerves! Ok, on to your problems: If you burn the new AVR code (from part 8) to the ATmega, it should show some startup text on the LCD screen without you even having to run interface.sh. Get this working first before you mess with the software on the router. You don't even need a serial connection. One thing that might be wrong is that your AVR might not have the right fuses programmed. Try running "make fuse" after you flash the firmware. I omitted this from the instructions in the post and that alone might fix your problem. Doublecheck your LCD wiring to the AVR. One wrong wire and the display will do what you describe. The dark first line is a sign that the LCD is not initialized. Either the AVR is not sending the right instructions or they aren't actually getting to the LCD. Are you using a Sparkfun LCD module? Some LCDs might not work with my code. Not all LCDs are created equal, some have different driver ICs on them. Admittedly I have never run across an LCD that I was not able to get some output from, so this is most likely not your problem. But checking another LCD woudln't be a bad idea if everything else fails... By the way, I have noticed the router rebooting issue also. To avoid this, I don't mess with the serial connections while the router is powered up. I just connect the AVR and leave it connected the whole time the router is on. I'm not sure why this happens. Jeff Hey Foo,

First of all, I created a new forum for this project over at

http://mightyohm.com/forum/viewforum.php?f=2

to help facilitate discussions like these. I know using the blog comment area exclusively for support was starting to get on some people’s nerves!

Ok, on to your problems:
If you burn the new AVR code (from part 8) to the ATmega, it should show some startup text on the LCD screen without you even having to run interface.sh. Get this working first before you mess with the software on the router. You don’t even need a serial connection.

One thing that might be wrong is that your AVR might not have the right fuses programmed. Try running “make fuse” after you flash the firmware. I omitted this from the instructions in the post and that alone might fix your problem.

Doublecheck your LCD wiring to the AVR. One wrong wire and the display will do what you describe. The dark first line is a sign that the LCD is not initialized. Either the AVR is not sending the right instructions or they aren’t actually getting to the LCD.

Are you using a Sparkfun LCD module? Some LCDs might not work with my code. Not all LCDs are created equal, some have different driver ICs on them. Admittedly I have never run across an LCD that I was not able to get some output from, so this is most likely not your problem. But checking another LCD woudln’t be a bad idea if everything else fails…

By the way, I have noticed the router rebooting issue also. To avoid this, I don’t mess with the serial connections while the router is powered up. I just connect the AVR and leave it connected the whole time the router is on. I’m not sure why this happens.

Jeff

]]> By: Foo Plinger http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3650 Foo Plinger Sat, 04 Apr 2009 03:56:41 +0000 http://mightyohm.com/blog/?p=822#comment-3650 I hate there isn't an edit or remove button for the posts..... Anyway, me, yet again. I have the radio working, I have the LCD working, but I still can't get it to display what is playing....Right now all I have on the LCD display is a repeating message about our kind host and project owner, MightyOhm. At one point I just gave up on display.sh and skipped to part 8, loaded display2.sh and interface.sh, and flashed with the new code, I think that is when I started getting the message on the lcd. I don't understand the whole deal with setting the router to 192.168.1.1, once I did that, no more connectivity, therefor, nothing to display since I couldn't get to any of the radio stations. I took out the static ip, and rebooted, and now when I run interface.sh, it just hangs...no output, and that is even after downloading it a second time. Is there somewhere else I can ask for help, has anyone gotten this working according to the instructions, or has everyone taken off in different directions? Not much help in the comments on hackaday either. I feel like I am close, but Jeff may be skipping something he feels is so basic it doesn't bear repeating...trust me, there is nothing too basic to tell me on this. Thanks for anyone that can comment. PS, in all the code examples, it says "changes in bold". Nothing is in bold for me. I hate there isn’t an edit or remove button for the posts…..
Anyway, me, yet again. I have the radio working, I have the LCD working, but I still can’t get it to display what is playing….Right now all I have on the LCD display is a repeating message about our kind host and project owner, MightyOhm.

At one point I just gave up on display.sh and skipped to part 8, loaded display2.sh and interface.sh, and flashed with the new code, I think that is when I started getting the message on the lcd. I don’t understand the whole deal with setting the router to 192.168.1.1, once I did that, no more connectivity, therefor, nothing to display since I couldn’t get to any of the radio stations.
I took out the static ip, and rebooted, and now when I run interface.sh, it just hangs…no output, and that is even after downloading it a second time.
Is there somewhere else I can ask for help, has anyone gotten this working according to the instructions, or has everyone taken off in different directions?
Not much help in the comments on hackaday either. I feel like I am close, but Jeff may be skipping something he feels is so basic it doesn’t bear repeating…trust me, there is nothing too basic to tell me on this. Thanks for anyone that can comment.

PS, in all the code examples, it says “changes in bold”. Nothing is in bold for me.

]]> By: Foo Plinger http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3642 Foo Plinger Fri, 03 Apr 2009 17:49:14 +0000 http://mightyohm.com/blog/?p=822#comment-3642 OK, thanks. I just got my crystal and some other parts from sparkfun. Bad news is, still no display on the LCD. Is there anyway to use my multimeter to monitor the output of the Atmega pins? I don't believe it is the problem, as I have successfully flashed the code on it a few times from blinky led to the code I DL from you, Connecting the serial port of the router to a hyperterminal shows the output I am expecting. The LCD lights up (backlights) and the contrast pot makes it brighter and dimmer (though only the top line). Seeing if the signal I should be getting from the controller is actually coming out of the pin I expect would help. Thanks! OK, thanks. I just got my crystal and some other parts from sparkfun. Bad news is, still no display on the LCD.
Is there anyway to use my multimeter to monitor the output of the Atmega pins? I don’t believe it is the problem, as I have successfully flashed the code on it a few times from blinky led to the code I DL from you, Connecting the serial port of the router to a hyperterminal shows the output I am expecting.
The LCD lights up (backlights) and the contrast pot makes it brighter and dimmer (though only the top line). Seeing if the signal I should be getting from the controller is actually coming out of the pin I expect would help. Thanks!

]]> By: Jeff http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3608 Jeff Mon, 30 Mar 2009 00:00:21 +0000 http://mightyohm.com/blog/?p=822#comment-3608 Most electronics stores will sell you a 16 MHz crystal. It can be almost any type. I think the HC-18 package is the most common.. Here's one: http://www.allelectronics.com/make-a-store/item/CRY-1618/16-MHZ-CRYSTAL-HU-18/U-CASE/-/1.html Most electronics stores will sell you a 16 MHz crystal. It can be almost any type. I think the HC-18 package is the most common..

Here’s one:
http://www.allelectronics.com/make-a-store/item/CRY-1618/16-MHZ-CRYSTAL-HU-18/U-CASE/-/1.html

]]> By: Foo Plinger http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3591 Foo Plinger Sun, 29 Mar 2009 02:10:41 +0000 http://mightyohm.com/blog/?p=822#comment-3591 OK....after reading through the site and comments a few more times, I find that I need some sort of Crystal.... I find no specifications for this crystal other that it appears to be 16Mhz, can you give a part number or source please? OK….after reading through the site and comments a few more times, I find that I need some sort of Crystal….

I find no specifications for this crystal other that it appears to be 16Mhz, can you give a part number or source please?

]]> By: Foo Plinger http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3581 Foo Plinger Sat, 28 Mar 2009 00:55:47 +0000 http://mightyohm.com/blog/?p=822#comment-3581 Hey all.... I have the router playing, but running into 2 significant problems. 1) Half the time I attach to the serial header soldered onto the router, every light on the router lights up and it reboots. 2) I have succesfully flashed the controller with a LED Blinky program, and get success codes back when I flash the LCD code to it, but I have yet to see any character on the LCD. I am afraid most of the problem is that I somehow ended up with a 3+- volt lcd as opposed to the 5 volt. What modifications would be neccessary to make this work...the pin outs look exactly the same, but nothing shows up on the lcd (the backlight and contrast pot work). ADM1602K-NSW-FBS-3.3v Hey all….
I have the router playing, but running into 2 significant problems.
1) Half the time I attach to the serial header soldered onto the router, every light on the router lights up and it reboots.
2) I have succesfully flashed the controller with a LED Blinky program, and get success codes back when I flash the LCD code to it, but I have yet to see any character on the LCD. I am afraid most of the problem is that I somehow ended up with a 3+- volt lcd as opposed to the 5 volt. What modifications would be neccessary to make this work…the pin outs look exactly the same, but nothing shows up on the lcd (the backlight and contrast pot work).
ADM1602K-NSW-FBS-3.3v

]]> By: Jeff http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3132 Jeff Mon, 16 Feb 2009 19:51:07 +0000 http://mightyohm.com/blog/?p=822#comment-3132 It should be fine. I don't know how much overhead the power supply circuit has, but I would imagine that 50mA should be within the design limits. Make sure your LCD works on 3.3V, many are 5V only (like mine). It should be fine. I don’t know how much overhead the power supply circuit has, but I would imagine that 50mA should be within the design limits. Make sure your LCD works on 3.3V, many are 5V only (like mine).

]]> By: Aleksander Grande http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-3125 Aleksander Grande Mon, 16 Feb 2009 09:21:37 +0000 http://mightyohm.com/blog/?p=822#comment-3125 Hi Jeff! Nice project, I'm working on a similar project, but I'm using the Asus WL-500G Premium, om mine there is a 3.3v Out pin on the pcb, and im not sure if i can draw current from that to support the avr circuit, i have a 40x2 char lcd and basically the same curcuit that you have, it should not draw anymore than 50mA, any ideas ? Hi Jeff! Nice project, I’m working on a similar project, but I’m using the Asus WL-500G Premium, om mine there is a 3.3v Out pin on the pcb, and im not sure if i can draw current from that to support the avr circuit, i have a 40×2 char lcd and basically the same curcuit that you have, it should not draw anymore than 50mA, any ideas ?

]]> By: Mark http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-2936 Mark Fri, 30 Jan 2009 15:50:31 +0000 http://mightyohm.com/blog/?p=822#comment-2936 Hey Jeff, cool project. Have to get some parts ordered and then ill be able to build one myself. Hey Jeff, cool project. Have to get some parts ordered and then ill be able to build one myself.

]]> By: Jeff http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-2833 Jeff Tue, 20 Jan 2009 16:37:09 +0000 http://mightyohm.com/blog/?p=822#comment-2833 Too many distractions have been keeping me away from part 8. Unfortunately it's going to be a while longer. My plan is to use the A/D input of the AVR to read the position of a tuning knob, then transmit that position back to the router over the serial port. Some shell script magic will use that reading to change stations - if I can get it all working! Too many distractions have been keeping me away from part 8. Unfortunately it’s going to be a while longer. My plan is to use the A/D input of the AVR to read the position of a tuning knob, then transmit that position back to the router over the serial port. Some shell script magic will use that reading to change stations – if I can get it all working!

]]> By: abel http://mightyohm.com/blog/2008/12/building-a-wifi-radio-part-7-building-an-lcd-display/comment-page-1/#comment-2809 abel Mon, 19 Jan 2009 02:05:16 +0000 http://mightyohm.com/blog/?p=822#comment-2809 good work. I am waiting for next part. when part8 is coming? good work.
I am waiting for next part.
when part8 is coming?

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