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== Special Loaders 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

Loading from cassette effectively uses all the CPU's time because you have to keep checking it must poll the cassette signal input in order to see if it has changed, convert the sound into data.So to do music and you use a CPU other things during loading requires precise timing loop to calculate length of signal.

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

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.