Difference between revisions of "Loaders"

From CPCWiki - THE Amstrad CPC encyclopedia!
Jump to: navigation, search
(Cassette)
m (Updated and added some details on tape loaders)
Line 30: Line 30:
 
*[[Rainbow Arts Decryption Key]]
 
*[[Rainbow Arts Decryption Key]]
 
*[[Lone Wolf Loader]]
 
*[[Lone Wolf Loader]]
 +
*[[Multiload Tape Loading System]]
  
 
== Disc ==
 
== Disc ==
Line 43: Line 44:
 
This list is not complete:
 
This list is not complete:
  
* [[Deflektor]] had a loader which showed instructions while loading
+
* [[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
 +
* [[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
 
* [[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
 
* [[Speedlock]] had colourful stripes in the border, some versions loaded the screen from top-to-bottom line by line
Line 65: Line 68:
 
|Game
 
|Game
 
|Loading music
 
|Loading music
 +
|-
 +
|Bomb Scare
 +
|
 
|-
 
|-
 
|Booty  
 
|Booty  
Line 71: Line 77:
 
|Comet Game (The)  
 
|Comet Game (The)  
 
|[[Media:Comet_game_%28the%29-loader.ym|Media:Comet_game_(the)-loader.ym]]<br>  
 
|[[Media:Comet_game_%28the%29-loader.ym|Media:Comet_game_(the)-loader.ym]]<br>  
 +
|-
 +
|Druid
 +
|
 
|-
 
|-
 
|Harvey Headbanger  
 
|Harvey Headbanger  
 
|[[Media:Harvey_headbanger-loader.ym|Media:Harvey_headbanger-loader.ym‎]]  
 
|[[Media:Harvey_headbanger-loader.ym|Media:Harvey_headbanger-loader.ym‎]]  
 +
|-
 +
|Helichopper
 +
|
 +
|-
 +
|Rasputin
 +
|
 +
|-
 +
|Runestone
 +
|
 
|-
 
|-
 
|Thrust
 
|Thrust

Revision as of 14:04, 18 November 2018

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:

Known protection schemes  :

Disc

This list is not complete:


Specific loaders worth looking at

This list is not complete:

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 (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 or for music.

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

Game Loading music
Bomb Scare
Booty
Comet Game (The) Media:Comet_game_(the)-loader.ym
Druid
Harvey Headbanger Media:Harvey_headbanger-loader.ym‎
Helichopper
Rasputin
Runestone
Thrust Media:Thrust.ym
Spiky Harold Media:Spiky_harold-loader.ym

Disc

The disc system on the Amstrad (and Spectrum +3) is "polled" which means the CPU has to keep checking if the FDC (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 Demo 3 
Midline Process 
Orion Prime
Batman Forever