I’m sure no one noticed, but the server was down for about a week or so. I was getting some disturbing output straight to my console about file io failures that repeated constantly and would not even allow you to work on stuff in the foreground.

The server had a 20gig drive with linux, a 30 gig drive with the web files and a 130gig disk for storage. All these were crammed into a very small computer. Anyway the 20 gig was failing, so I made a backup using dd onto another partition of the 130gig. Then I spent about 3 days trying to get the system to boot from the 130gig hdd to no avail. It seems that something in that drive will just not allow it to boot. I had figured this out before and thats why i was using it for storage. Anyway that caused me to learn a lot about grub and lilo. I just reformatted the 20 gig drive and reinstalled the os on it. I ended up using grub, I also ended up using a different OS.

I tried the latest version of slackware, I figured since i was reinstalling midas well get the latest version. I hated it ! They use the resource heavy KDE, there is no apt-get or yum like functionality. They still have that package system where you have to use pkg-tool in the dir where you have downloaded packages and then go through each one and say yes or no. It is incredibly hard to get those packages, you might know you need a program to do this but unless you know its called progname.ver.somecrazystuff.tar.tz.ver34 good luck finding it on their site. You could also just browse through thousands of packages separated alphabetically and say “maybe this is what i need?” Since I’m also familiar with ubuntu i got the ubuntu server version.

The installation of ubuntu was fast and easy. The boot cd also has a way to load a kernel so you can get in and do stuff like “grub-install” (which does not exist for slackware). After I installed Ubuntu I got my firewall script to work just fine on it. Everything i wanted i just “sudo apt-get install” ed it. Ubuntu also comes with awesome tools like gnu screen and nano, it also has a updated version of vi I had not seen before. And of course the updates in ubuntu are a snap, so i wont end up with a OS that has not been upgraded for 2 years like I did with the version of slackware that crashed.

I did very much like the old version of slackware, version 10 or 11 I think. I loved the way it gave random quotes every time you log in. Also the boot cd allows you to specify a different kernel, which i couldnt figure out how to do with the ubuntu cd. This was very helpful when i had 3 different partitions i was trying to boot. But besides that i’m sticking with ubuntu with xfce4 installed !

Everything is up and running now, obviously. I had backups so most of the stuff got restored. A lot of the stuff got a nice cleaning, i had a lot of junk ! Wordpress turned out to be easy to restore thanks to their backup/restore tools. For my other custom web page (social network site) I opted out of my custom stuff and installed dolphin, the dolphin install took me a few hours then i wrote some scripts to do some crazy stuff with the mysql database so all 500 users from before would just pop up in the totally different social networking software, that was not easy but I was able to do it. I had to also write scripts to resize their photos and store them in directories and all kinds of crazy stuff. If you need to port some site to a dolphin site let me know I can help.

I always have been good with backups, but now I keep a duplicate of the entire linux root disk so i can at any time swap it out and replace it without delay. I’m using the dd for most of that.

I will write about my updated firewall script and the other stuff I did to get the ubuntu system to do all that my slackware system did, just got to get some free time. I’ve also made some diagrams and such, hope to write about that soon.

Today I noticed that I had lost all the work I did over summer (which was a bunch). I was able to find them in old binary files for mysql but the pictures and attachments are all gone for good. Here is what wp told me

   1. Importing post Using IPTABLES on your linux router... (2 comments)
   2. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/simplers232.jpg
   3. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/ttl-rs232-conv-top.jpg
   4. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/ttl-rs232-conv-back.jpg
   5. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/card-reader-conv.gif
   6. Importing post RS-232 to serial Conversion, using 2 transistors... (1 comment)
   7. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/pic-blew-up.jpg
   8. Importing post Blow UP your Pic's...
   9. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/rf-out-backspace-fullshot.jpg
  10. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/rf-out-tab-fullshot.jpg
  11. Importing post SoundCard Oscilloscope...
  12. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/protoboard-02-top.jpg
  13. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/protoboard-02-bottom.jpg
  14. Importing post Protoboard Version 0.2... (2 comments)
  15. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/pic-uart-aa.jpg
  16. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/rs232-a.jpg
  17. Importing post RS232 Revisited... (1 comment)
  18. Importing post Standard Lab Journal Format that I will be using... (1 comment)
  19. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/network-setup.jpg
  20. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/firewall-flow-chart.jpg
  21. Importing post My Linux Firewall Script... (43 comments)
  22. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/rcr-rx-breadboard.jpg
  23. Skipping attachment http://zonemikel.com/wordpress/wp-content/uploads/2009/05/rcr-tx-protoboard.jpg
  24. Importing post Testing RCT-433-AS-TRANSMITTER and RCR-433-RECIVER... (10 comments)
  25. Importing post Ubuntu + VirtualBox + Existing WinXP 64 Hopefully !:... (6 comments)
  26. Importing post Ubuntu 9.04 + Virtual Box (non ose) + usb grayed out... (32 comments)

At least i got the information back and i wont have to start out from scratch when i pick up those projects again. If i find the pictures i will upload them so they show up.

to solve this

add yourself to the virtual box group

type “grep vboxusers /etc/group” to get your id .. it will be the number

add
none /proc/bus/usb usbfs devgid=###,devmode=664 0 0
to your /etc/fstab where ### is the number you got with the previous command.

i tried all the other stuff, spent all day on it this worked .. if you have version 9.04 of ubuntu do this ! If you have VirtualBox ose from the package manager your usb devices wont work at all. Just go to the virtual box webpage and get the deb.

Brief Description

My purpose was to test this transmitter/receiver pair to see how far i could go and still reliably transmit data. I used my protoboard to transmit. The reciever was attached to a uart to rs232 converter then to the db9 port on my computer and i watched the input from hyperterminal.

Equipment

• ProtoBoard
• rct-433-as transmitter Mouser Part # 509-RCT-433-AS
• rcr-433 reciever Mouser Part #509-RCR-433-RPR
• A transistor and some 10K resistors for Conversion
• A few 4.7uF and .01uF Filter Capacitors
  

Prelab

Get and study data sheets for the transmitter and reciever. Brush up on rs-232 and ttl signaling levels.

Procedure

The first thing i did was get the Conversion circuit working. I’ve found that the other circuit i have listed does not work well with the 2N3904/6 transistors that i have on hand. I was only able to get the uart to rs232 portion to work, as soon as i plugged in the capacitor or the line going to rs-232 RX the circuit would stop working. So I only hooked up half of the ciruit using a 2N3906 and three 10K resistors. You can do that or use the other one way circuit. You should be comfortable enough with the signalling levels by this point to do this easily, if not i suggest you go back to those sections.

After thats hooked up connect it to the tx pin on the pic to make sure its transmitting correctly. Then hook up the reciever and put the data out line where your pic was connected (before the 10K going into the base of the transistor). You can get the data sheets for the reciever and transmitter in the links that i posted above in the equipment bullets. Hooking up the reciever is really simple, its just ground and power lines and a data out. I hook up all the ground and power lines just to be sure, and when in doubt remember vsS = “sink” so its the ground.

I hooked the transmitter into my “protoboard”.

There is a program on the pic that just transmits a number like 10 times and then does a newline. That way i can print out lots of data and see what number it messed up on. I used the lowest setting i could for the pic, since it has a 20Mhz clock i can use any baud rate slower than 1200.

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31

#include <16F877.h>
#device adc=8
#use delay(clock=20000000)
#fuses NOWDT,HS,NOPUT,NOLVP
#use rs232(baud=1200,parity=E,xmit=PIN_C6,rcv=PIN_C7,bits=8)
int i =0;
int j=0;
void main()
{
   setup_adc_ports(NO_ANALOGS);
   setup_adc(ADC_OFF);
   setup_psp(PSP_DISABLED);
   setup_spi(FALSE);
   setup_timer_0(RTCC_INTERNAL|RTCC_DIV_1);
   setup_timer_1(T1_DISABLED);
   setup_timer_2(T2_DISABLED,0,1);
 
   output_b(0xFF);
 
   printf("\f \f \f \r \f \f \f \r \f \f \f \r");
   printf("Start");
   while(1){
      for (j=0;j<10;j++){
      printf(".%i",i);
      }
      printf("\r\n");
      i++;
 
   }
 
}

Filter Capacitors
In the datasheet for both the transmitter and reciver it says you should use a “bypass” and “filter” cap. I noticed a great improvement of signal quality when i installed these. Pretty much for both of them i just connected them between ground and power in close proximity to the chip, I did this on both the tx and rx ends. You should be able to make it out from the pictures.

Antenna
There is some weird calculation to get “1/4″ of the wave or soemthing like that to calculate the optimum lenght of the antenna. Other people calculated it to 17cm. POST LINK HERE So, I just used a 17cm peice of telephone wire.

Conclusions

The pair works pretty good going at 1200 baud, I was able to transmit through walls. I transmitted at least 20 feet away through walls without loosing any info. This was only after installing the filter capacitors though.

In the datasheets it recommends that you invert the output signal on both ends. This allows you to only transmit when you are actually transmitting, if you dont do this to hold the line without sending data you have to send a ‘1′, but if you invert before it hits the transmitter and then invert coming out of the reciever then you wont need to waste power. If you are transmitting from the pic then you need to set the INVERT option in your program, or you can just invert after that. I didnt implement this part but i might later on.

When you are not transmitting the reciever picks up some weird square wave that does strange things. Then, when you start to transmit some of this weird square wave is picked up in the beggining of your signal, this almost always makes the first part of a string of data get garbled. You can get around this by just constantly transmitting data, which might not be efficent. Possibly you could create some kind of circuit to filter this out, or maybe by inverting the singal it would help ? Just something to consider.

Depending on the needed applications of this it seems to be a very nice way to transmit data, I plan on making a RC car, for that it should work just fine.