Iphone 4 microphone fault

After being dropped or similar the audio compiler malfunctions. I proved the problem by placing a call and (removed back) pressed on the area where the compiler chip is and confirmed sound was working while pressing only.

Follow this for the best detailed removal and replacement video...

http://www.youtube.com/watch?v=DPR8qrAcg5g

Raspberry Pi Notes (img Backups)

If you have a good build and dont want to loose it....


Grab the SD card out and stick it in the mac, go to a terminal and type


# diskutil list

/dev/disk0
   #:                       TYPE NAME                                       SIZE            IDENTIFIER
   0:                       GUID_partition_scheme                        *251.0 GB   disk0
   1:                       EFI                                                       209.7 MB   disk0s1
   2:                       Apple_HFS Macintosh HD                     250.1 GB   disk0s2
   3:                       Apple_Boot Recovery HD             650.0 MB   disk0s3
/dev/disk1
   #:                       TYPE NAME                                      SIZE       IDENTIFIER
   0:                       FDisk_partition_scheme                        *2.0 GB     disk1
   1:                       Windows_FAT_32 System                    131.1 MB   disk1s1
   2:                        Linux                                                  805.3 MB   disk1s2

# umount /dev/disk1


# dd bs=1024 if=/dev/disk1 of=20130806-raspberry.img

This last one takes about 1/2 hour but it creates an img on the mac that can be dumped to another SD card at will later with:

# dd bs=1024 of=/dev/disk1 if=20130806-raspberry.img

This is how I keep backups of my good builds. Keep in mind that there is no compression involved and a 16G SD disk will take up 16G of space on the mac.

Raspberry PI Notes (Wifi and Bluetooth)

Wifi 

I used the following usb dongles without any trouble:

Edimax, Cisco (Linksys) WUSB600N, Belkin F7D1101 v1 

Edimax


> 802.11n WLAN Adapter:
>

> Product ID: 0x7811
> Vendor ID: 0x7392
> Version: 2.00
> Serial Number: 00e04c000001
> Speed: Up to 480 Mb/sec
> Manufacturer: Realtek
> Location ID: 0x1a120000 / 4
> Current Available (mA): 500
> Current Required (mA): 500



Cisco
< Linksys WUSB600N Wireless-N USB Network Adapter with Dual-Band ver. 2:
<
< Product ID: 0x0079
< Vendor ID: 0x1737 (Hong Kong Applied Science and Technology Research Inst.)
< Version: 1.01
< Speed: Up to 480 Mb/sec
< Manufacturer: Linksys
< Location ID: 0x1a120000 / 4
< Current Available (mA): 500
< Current Required (mA): 450



Belkin
> Basic Wireless USB Adapter:
>
> Product ID: 0x945a
> Vendor ID: 0x050d (Belkin Corporation)
> Version: 2.00
> Serial Number: 00e04c000001
> Speed: Up to 480 Mb/sec
> Manufacturer: Manufacturer Realtek
> Location ID: 0x1a120000 / 4
> Current Available (mA): 500
> Current Required (mA): 500


Bluetooth 

I used this guide to get me started installing the bluez stack etc:http://www.ctheroux.com/2012/08/a-step-by-step-guide-to-setup-a-bluetooth-keyboard-and-mouse-on-the-raspberry-pi/

keyboard: I used an apple keyboard and magic mouse, using a old dongle I found from ISSC (this information is from the dongle):


> ISSCEDRBTA:
>

> Product ID: 0x1001
> Vendor ID: 0x1131 (Integrated System Solution Corp.)
> Version: 3.73
> Speed: Up to 12 Mb/sec
> Manufacturer: ISSC
> Location ID: 0x14200000 / 7
> Current Available (mA): 500
> Current Required (mA): Unknown (Device has not been configured)


Make the keyboard discoverable (I took the batteries out and put back, then press button on side, green light should flicker on and off).

record the MAC address

# hcitool scan

pair it
# echo 0000|bluez-simple-agent hci0 BB:0F:FE:82:D1:C5

Then enter 0000 on BT keyboard
trust the keyboard...

# bluez-test-device trusted BB:0F:FE:82:D1:C5 yes

connect the keyboard...

# bluez-test-input connect BB:0F:FE:82:D1:C5


Make the mouse discoverable ( I switched it off and on again)

# hcitool scan

record the MAC address

# echo 0000|bluez-simple-agent hci0 BB:0F:FE:82:D1:C6

trust the mouse...

# bluez-test-device trusted BB:0F:FE:82:D1:C6 yes

connect the mouse...

# bluez-test-input connect BB:0F:FE:82:D1:C6

All devices remain intact on reboot.

Using systemd in Fedora.....

To permanently enable a service:

#  systemctl enable ntpd.service

To start it:

# systemctl start ntpd.service

To view all services:

# systemctl

Finding Disk Hogs

Finding disk hogs

# du  /home/* | sort -n -r | less

Adding constraints to mysql tables

When we have content in a table that is dependant on another a constraint is required. With Mysql an InnoDB type is required otherwise the constraint is silently ignored. Consider a radios table, models table and a code_plugs table within the radio database.

The constraints would prevent a code_plug or models record being removed if a relative record in the radios table exists.


The create table entries would be:

CREATE TABLE `radios` (
  `id` int(4) NOT NULL AUTO_INCREMENT,
  `status_id` int(4) NOT NULL DEFAULT '2',
  `model_id` int(4) NOT NULL,
  `serial_number` varchar(40) NOT NULL,
  `software_version` varchar(40) NOT NULL,
  `active` int(4) NOT NULL DEFAULT '1',
  `remarks` varchar(100) NOT NULL,
  `code_plugs_id` int(4) NOT NULL,
  `radio_id` int(4) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `serial_number` (`serial_number`),
  UNIQUE KEY `radio_id` (`radio_id`),
  CONSTRAINT `FK_code_plugs` FOREIGN KEY (`code_plugs_id`) REFERENCES `code_plugs` (`id`),
  CONSTRAINT `FK_models` FOREIGN KEY (`model_id`) REFERENCES `models` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1376 DEFAULT CHARSET=latin1;


CREATE TABLE `models` (
  `id` int(4) NOT NULL AUTO_INCREMENT,
  `model` varchar(20) NOT NULL,
  `type` varchar(20) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=11 DEFAULT CHARSET=latin1;


CREATE TABLE `code_plugs` (
  `id` int(4) NOT NULL AUTO_INCREMENT,
  `name` varchar(40) NOT NULL,
  `description` varchar(200) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1112 DEFAULT CHARSET=latin1;



A simple snippet of perl server side code to provide an xml response to a delete attempt would look like:


my $dbh = DBI->connect("dbi:mysql:radio",$dbuser,$dbpass,{RaiseError=>0});
my $id = param("id");
my $table = param("table");

my $rows = $dbh->do("DELETE FROM $table WHERE id = \'$id\';");
my $result;
if($dbh->errstr){
        $result = $dbh->errstr;
        $result =~ s/([\',\`])+//g;
}else{
        $result = $rows;
}

# results are 1 for success and 0E0 for failure
my $xml = '<?xml version="1.0"?>';
$xml .= "\n<options>\n";
$xml .= "<option result=\'$result\' />\n";
$xml .= "</options>";
print "$xml";

A simple javascript handler for the delete may look similar to :


function deleteID(id,table){
        if (confirm("Are you sure?")){
                var request;
                try{
                        request = new XMLHttpRequest();
                }catch(error){
                        try{
                                request = new ActiveXObject("Microsoft.XMLHTTP");
                        }catch(error){
                                return true;
                        }
                }
                request.open('GET', '/cgi-bin/deleteUsingID.pl?id=' + id + '&table=' + table,true);
                request.onreadystatechange = function(){
                        if(request.readyState == 4){
                                var xmlDoc = request.responseXML;
                                var options = xmlDoc.documentElement.getElementsByTagName("option");
                                for (var x = 0; x < options.length; x++){
                                        var result = (options[x].getAttribute("result"));
                                        if (result == '1'){
                                                var rid = 'row_' + id;
                                                var oTable = document.getElementById('content_table');
                                                var oTr = document.getElementById(rid);
                                                oTable.deleteRow(oTr.rowIndex);
                                        }else{
                                                alert(result);
                                        }
                                }
                        }
                }
                request.send(null);
        }
}

Removing files older than 5 minutes.

Quickly list files with time of last modification:
# ls -alt

If you need to remove any that have not been modified lately:

1. verify files that will be worked on by running with ls first
2. delete at will without warning

# find ./*.rrd -type f -mmin +5 -exec ls {} \;

# find ./*.rrd -type f -mmin +5 -exec rm {} \;