Difference between revisions of "Loaders"

From CPCWiki - THE Amstrad CPC encyclopedia!
Jump to: navigation, search
m (Updated and added some details on tape loaders)
m (Added info on The Mark Time Music Box)
 
(One intermediate revision by the same user not shown)
Line 46: Line 46:
 
* [[Deflektor]] had a loader which showed instructions while loading - see [[Multiload Tape Loading System]]
 
* [[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
 
* [[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
 
* [[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
* Some firebird games had music while loading from tape (see below).
+
* Some Firebird games had music while loading from tape (see below).
  
 
== Loading music  ==
 
== Loading music  ==
Line 60: Line 61:
 
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.
 
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 or for music.  
+
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 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 of the loading music soon.  
 
This list is not complete, please add more. Will upload YM of the loading music soon.  

Latest revision as of 16:52, 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.

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 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