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  • Jay Versluis 1:42 pm on August 30, 2014 Permalink | Reply
    Tags: , , , sd2iec   

    Categories: Commodore ( 15 )

    How to use SD2IEC: a quick command reference 

    Photo 28-08-2014 19 30 57
    I’ve ordered an SD2IEC a few weeks ago from Nic over at http://sd2iec.co.uk. It’s an SD card reader for Commodre computers and emulates many features of the 1541 Floppy Disk Drive.

    I went for the Limited Edition made from authentic recycled C64 plastic – so this little critter used to be a real C64! This has to be one of the coolest gadgets for any Commodore fan in the 21st century.

    Nic and several other sellers on eBay build the hardware, while the software was developed by Ingo Korb with contributions from others. In this article I’ll explain how you can get the most out of the SD2IEC.

    Reading and Writing Files

    The SD2IEC works out of the box with standard disk commands (such as LOAD and SAVE). This will save a BASIC programme as PRG just like your Commodore would save it to floppy disk.

    You can create, switch into and remove directories on the SD card with your SD2IEC (or your “contemporary” computer of course). You can also read from and write to D64/D71/D81 image files and I’ll explain how this works further down.

    When you’re in a subdirectory (or a disk image) all read/write operations are performed there until you switch images or directories. We can do this by communicating with the SD2IEC via the command channel, as if we’re speaking to a 1541.

    Looks like the SD card is hot-swappable without the need to “safe-eject” as long as none of the lights are on, indicating read/write access.

    Speaking to your SD2IEC

    To issue commands on your SD2IEC we must open that trusty old command channel on the device (number 15), PRINT# the command and then optionally close the channel again. Here’s how to do that:

    OPEN 15,8,15
    PRINT#15,”your command here”
    CLOSE 15
    

    You can also write this on a single line:

    OPEN 15,8,15,”your command”:CLOSE 15
    

    You can also leave channel 15 open and issue more commands. Notice though that if you use any other disk command after opening channel 15 (such as LOAD or SAVE) all channels including 15 are closed automatically. Commands such as DIRECTORY do not close the channel.

    I find it helpful to add these things to one my my programmable keys (C128 and Plus/4) via the KEY command:

    // open command with trailing quotes
    KEY 1,"OPEN 15,8,15,"+CHR$(34)
    

    Hit F1, then type one of the commands below. If the channel is already open, simply issue the command via PRINT#15,”command”.

    Directories

    The CD command lets you navigate the directory structure much like you would in Linux and Windows from the command line.

    // change into the root directory
    CD//
    
    // enter directory “mydir” (relative to where you are)
    CD/mydir/
    
    // enter directory “mydir” (absolute from root directory)
    CD//mydir/
    
    // navigate up one level (like the Linux cd .. command)
    CD:←
    

    You can also create directories to start organised without the need for other tools. That’s where the MD command comes in handy:

    // create directory in the current location
    MD:mydir
    
    // create directory inside another directory
    MD/mydir/:otherdir
    
    // create a directory absolute to root
    MD//mydir/:otherdir
    

    When you’re done with a directory you can delete it with RD. Note that only empty directories can be deleted, otherwise you’ll get a FILE EXISTS error:

    // remove in current directory
    RD:mydir
    
    // remove directory absolute to root
    RD//mydir/:otherdir
    

    Mounting Disk Images

    The CD command can also be used to mount D64/D71/D81 image files, just as if they were standard directories. The same syntax applies as with switching directories:

    // mount “myimage.d64” in current directory
    CD:myimage.d64
    
    // mount “myimage.d64” in subdirectory /mydir (relative)
    CD/mydir/myimage.d64
    
    // or absolute
    CD//mydir/myimage.d64
    
    // unmount a disk image (go back SD card directory in which the image resides)
    CD:←
    

    You don’t have to mount disk images of course and can instead use a FAT or FAT32 formatted SD card just like it was a floppy disk. However, CBM DOS can only address a maximum of 144 files in a directory which means that a cheap 4GB SD card will be exhausted by this limitation before it’s anywhere near full.

    Changing the Device Address

    By default the SD2IEC is set to be drive number 8. But like its vintage counterpart you can change this to 9,10 or 11 using the following command:

    // change from drive 8 to drive 9
    OPEN 15,8,15
    PRINT#15,“U0>"+CHR$(9)
    CLOSE 15
    

    Replace the CHR$ value with the desired drive number. Just like a real 1541 drive, the SD2IEC will not remember this change upon reset. You can however save the above to its internal EEPROM which will survive subsequent reboots:

    // save drive number to EEPROM
    OPEN 15,9,15
    PRINT#15,“XW"
    CLOSE 15
    

    Replace 9 with your actual drive number.

    Troubleshooting

    If you encounter flashing lights on your device, then the SD2IEC is trying to tell you something. On the C128 and Plus/4 you can read out the disk error channel by looking at the DS$ system variable:

    // print disk error channel on C128 and Plus/4
    PRINT DS$
    

    This will show you what went wrong (FILE EXISTS, FILE NOT FOUND, etc). On the C64 this is a little harder and requires you to write a small programme to read those values out. This is necessary because the INPUT# command can not be used in direct mode:

    // read disk error channel on C64
    10 open 15,8,15
    20 input#15,a,b$,c,d
    30 print a;b$,c,d
    40 close 15
    

    There’s a lot more you can do with this device – check out the full documentation in the README file at Ingo Korb’s website:

     
  • Jay Versluis 12:52 pm on August 26, 2014 Permalink | Reply
    Tags:   

    Categories: Linux ( 46 )

    What is the End-of-Life (EOL) for CentOS Distributions 

    The End-of-Life (EOL) for CentOS Distributions is as follows:

    Screen Shot 2014-08-26 at 12.46.37

    More under Section 21 in this article:

     
  • Jay Versluis 8:13 am on August 25, 2014 Permalink | Reply  
    Categories: Plesk, Screencasts ( 35 )

    Managing Email Accounts in Plesk 12 

    In this screencast I’ll explain how to setup Email Accounts in Plesk 12. I will show you how to setup mailboxes, use forwarding and create aliases. I’ll also show you the Spam Filter and Auto Responder.

    This all happens in Plesk, there’s another video which will show you how to check email from an external client and via webmail.

     
  • Jay Versluis 6:07 pm on August 23, 2014 Permalink | Reply
    Tags: , Yosemite   

    Categories: How To ( 25 )

    How to enable automatic user logins on Mac OS X Yosemite 

    Screen Shot 2014-08-23 at 17.49.01By default Yosemite doesn’t like users to auto-login when the system starts. Instead you have to select a user, type in the password, and then the system starts to boot. Not necessarily what we want.

    To disable this feature you usually head over to

    • System Preferences
    • Users and Groups
    • Login Options

    and pick your default user from that handy drop down menu. Notice however that this is greyed out on Yosemite:

    Screen Shot 2014-08-23 at 17.47.59

    So what gives?

    Turns out that this option is not available if you’ve agreed to encrypt your disk via FileVault. And it makes sense too: otherwise your hard disk data could be accessed upon boot without a password, rendering this feature useless.

    Hence, to bring back automatic logins, turn off FileVault under

    • System Preferences
    • Security and Privacy
    • FileVault

    Screen Shot 2014-08-23 at 17.56.24

    According to this system, I can do that in about 32 days…

    Notice that if you use your iCloud password as the login password, auto-logins are also disabled. In which case, change your login password to a “separate password”, switch off FileVault and voila – auto logins are back at your disposal.

    Screen Shot 2014-08-23 at 18.02.06

     
  • Jay Versluis 7:01 am on August 18, 2014 Permalink | Reply
    Tags: Health Monitor   

    Categories: Plesk, Screencasts ( 35 )

    How to adjust Health Monitor Alarms in Plesk 

    In this screencast I’ll show you how to adjust the Health Monitor thresholds. Those are the ones that tell Health Monitor when to send an email and when to display a “Needs Attention” or “Problem” message.

    Health Monitor works with XML configuration files which can easily be changed to suit your needs.

    In this example, one of my servers has seen an increase in Apache CPU usage and has been bombarding me with emails because the “Problem” threshold is set to trigger at 25%. After investigating the issue I’ve increased this value to 95% and now I can sleep a little easier.

     
  • Jay Versluis 7:32 am on August 11, 2014 Permalink | Reply
    Tags:   

    Categories: Plesk, Screencasts ( 35 )

    How to upgrade from Plesk 11.5 to Plesk 12 on CentOS 

    In this screencast I’m showing you how to upgrade from an older version to Plesk 12. Specifically, I’m showing this with a Plesk 11.5 installation, but the principles still apply from Plesk 10.x onwards.

    Plesk 12 comes in four flavours, and depending on the previous license you’ve held you’ll be upgraded to one of the new types – check them out here:

     
  • Jay Versluis 11:54 am on August 7, 2014 Permalink | Reply
    Tags: Assembly,   

    Categories: Commodore ( 15 )

    How to locate and set the cursor on your Commodore C128 

    Commodore LogoSadly the Commodore machines don’t offer a routine to locate or set the current cursor position via BASIC. There is however a Kernel routine named PLOT which can do this in Machine Language.

    Here’s how we can utilise it.

    Getting the Cursor Position

    . 01300  38       sec
    . 01301  20 f0 ff jsr $fff0
    . 01304  8e 00 14 stx $1400
    . 01307  8c 01 14 sty $1401
    . 0130a  60       rts
    

    This snippet sets the carry flag, calls the PLOT routine at $FFF0 and returns the cursor position in the X and Y registers. We’ll put them in a safe place into $1400 and $1401 to use.

    You can call it from BASIC with

    SYS DEC("1300")
    PRINT PEEK(DEC"1400") : rem row
    PRINT PEEK (DEC("1401") : rem coumn
    

    Setting the Cursor Position

    . 01310  18       clc
    . 01311  ae 00 14 ldx $1400
    . 01314  ac 01 14 ldy $1401
    . 01317  20 f0 ff jsr $fff0
    . 0131a  60       rts
    

    Call it from BASIC by POKEing your desired coordinates into $1400 and $1401, then call SYS DEC(“1310″).

    This snippet will do the reverse of the above: populate the X and Y registers from our safe place and then call PLOT. We clear the carry flag first, because it decides if the position is read (carry clear) or set (carry set).

    PLOT should work fine on the C64 and Plus/4 as well but I didn’t get a chance to test it yet.

     
  • Jay Versluis 11:46 am on August 4, 2014 Permalink | Reply
    Tags:   

    Categories: iOS, Screencasts ( 219 )

    Core Data Nugget #1: How to speak Core Data 

    In this screencast I’ll talk you through the lingo of Core Data: those scary classes and expressions that you’ll frequently come across. In fact, this is the start of a new series:

    Core Data Nuggets are bite-sized chunks about the framework. Dip in and out or watch them all in a row and learn how this super complicated framework works and what it has to offer.

    Don’t get overwhelmed by Core Data: it wants to help – it’s just not designed with humans in mind.

    As always, enjoy!

     
  • Jay Versluis 2:55 pm on July 31, 2014 Permalink | Reply
    Tags: , Microsoft, Office,   

    Categories: Bookmarks, Screencasts ( 17 )

    How to update Microsoft Office for Mac 2011 – despite Microsoft Database Daemon and SyncServicesAgent errors 

    Every time I try to update Microsoft Office 2011 on my Mac I get this ridiculous window popping up. No matter how hard you try, those two services – Microsoft Database Daemon and SyncServicesAgent – keep relaunching themselves, forever preventing you to apply the update.

    Clearly Microsoft (or Apple) don’t want us to update Office for Mac:

    Screen Shot 2014-07-31 at 14.49.45Usually I give up and live without such updates. I only use M$ Office once in a blue moon and really don’t care. Today I got curious and researched this phenomenon – and thought I’d tell you about it.

    Several suggestions are available to combat this superb example of a terrible user experience:

    • rename those processes
    • log out, then log back in with the shift key held down
    • go offline just before this message comes up
    • kill the processes with the Activity Monitor Utility

    None of those suggestions worked for me, and besides: what a hack any of these solutions are to apply a simple security patch.

    What did work was a very clever suggestion by someone named vrleboss: Use a while loop on the command line and continually kill those processes until you’re done.

    Here’s how to do it: Open the Terminal utility on your Mac and paste the following code:

    while true; do kill $(ps -ef | grep -i SyncServices | grep -v grep | awk '{print $2} '); done

    You can do this without quitting anything else, even while the pesky “close applications” window is displayed. Make sure the whole command is on the same line. The is a BASH loop that will find both processes and kill them as soon as they start up again. Don’t worry about the continuous text output in the window.

    Back in the Microsoft Updater window, hit “Close Applications and Install”. Now it works!

    Once the update is applied, head back to the Terminal window and press CTRL+C – this will stop the killing loop. Close Terminal and Office for Mac is finally updated.

    Then repeat this process next week, when another 140MB of updates will have to be applied.

    Watch the Screencast

     
  • Jay Versluis 8:45 am on July 28, 2014 Permalink | Reply
    Tags:   

    Categories: Screencasts, Themes, WordPress ( 50 )

    How to use the TwentyThirteen Theme by Automattic 

    In this screencast I’ll show you how to use TwentyThirteen, a simple yet powerful WordPress theme that looks gorgeous and is mobile friendly. I’ll explain Post Formats and their impact, how to show images in galleries and how to embed videos to your WordPress site too.

    I’ll finish it off by demonstrating how the site looks like on a desktop browser as well as the iOS Simulator on iPad and iPhone. I’m using WordPress 3.9 for this demo.

    I’m referencing some related articles in this video – here they are:

     
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