View source for Loaders

A loader is a program that loads in new data for a game or program.
This section covers various types of loaders seen on the Amstrad.

== Cassette ==

This list is not complete:

*[[Custom Turbo Loader]]

Known protection schemes  : 

*[[Speedlock]]
*[[Alkatraz]]
*[[Bleepload 1]]
*[[Bleepload 2]]
*[[Gremlin Loader 1]]
*[[Gremlin Loader 2]]
*[[Gremlin Loader 3]]
*[[Operasoft Loader]]
*[[Unilode Loader]]
*[[Zydroload Loader]]
*[[Ricochet Loader]]
*[[Microkey Loader]]
*[[Poliload Loader]]
*[[ehService Loader]]
*[[MBC Loader]]
*[[Puffy's Saga Loader]]
*[[Technician Ted Loader]]
*[[Ariolasoft Decryption key]]
*[[Rainbow Arts Decryption Key]]
*[[Lone Wolf Loader]]
*[[Multiload Tape Loading System]]

== Disc ==

This list is not complete:
*[[Speedlock]]
*[[Hexagon]]
*[[Alkatraz]]


=== Specific loaders worth looking at ===

This list is not complete:

* [[Deflektor]] had a loader which showed instructions while loading - see [[Multiload Tape Loading System]]
* [[Blood Brothers]], [[City Slicker]], [[Costa Capers]] and [[The Final Matrix]] had the same loader as Deflektor
* [[Astro Marine Corps]] and [[Rescue From Atlantis]] had a loader with MasterMind game built-in, that can be played during loading
* [[Technician Ted]] had a loader with a dozen of main game character's sprites walking on the screen during loading
* [[Zynaps]] had a loader which had a countdown while loading
* [[Speedlock]] had colourful stripes in the border, some versions loaded the screen from top-to-bottom line by line
* Some Firebird games had music while loading from tape (see below).

== Loading music  ==

=== Cassette  ===

Loading from cassette effectively uses all the CPU's time because it must poll the cassette input in order to convert the sound into data.
So to do music and other things during loading requires precise timing. 

The C64 effectively had interrupt driven loading music and the serial chip handled clocking in of the data bits and signalled an interrupt when the byte of data was ready. This meant music during loading was much easier to achieve.

I think only Firebird games had loading music on cassette. The music was composed by Melvyn Wright ([http://www.melright.com www.melright.com]). The music data was embeded into the data on cassette. The data was read as a group of 3 bits and 8 data bits. The 3 bits determined if the 8 data bits were for data&nbsp;or for music.

The only other known software that plays music during loading from tape is [[The Mark Time Music Box‎]] music program.

This list is not complete, please add more. Will upload YM&nbsp;of the loading music soon. 

{| class="FCK__ShowTableBorders"
|-
|Game
|Loading music
|-
|Bomb Scare 
|
|-
|Booty 
|
|-
|Comet Game (The) 
|[[Media:Comet_game_%28the%29-loader.ym|Media:Comet_game_(the)-loader.ym]]<br> 
|-
|Druid 
|
|-
|Harvey Headbanger 
|[[Media:Harvey_headbanger-loader.ym|Media:Harvey_headbanger-loader.ym‎]] 
|-
|Helichopper 
|
|-
|Rasputin
|
|-
|Runestone 
|
|-
|Thrust
|[[Media:Thrust.ym]]
|-
|Spiky Harold 
|[[Media:Spiky_harold-loader.ym|Media:Spiky_harold-loader.ym]]
|}

=== Disc  ===

The disc system on the Amstrad (and Spectrum +3) is "polled" which means the CPU&nbsp;has to keep checking if the [[FDC]]&nbsp;(NEC765) has more data to read/write. On the C64 the disc system is interrupt driven. 

So to do music while loading requires careful timing and often the use of very small sectors (128bytes). 

 ZapTBalls 
 The Demo 
 5KB&nbsp;Demo 3 
 Midline Process 
 Orion Prime
 Batman Forever