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[[Image:rammusicmashineRammusicmashine.jpg|right|thumb|right|250px|The Ram Music Machine]]
A digital sound sampling and playback device. The Amstrad CPC version Music Machine was almost identical to the the ZX Spectrum version, only difference was the address decoding logicdesigned by Flare Technology and manufactured by [[Ram Electronics|RAM Electronics]].
The incomming signalo from the microphone amplifier is sampled to an 8-bit resolution at a rate of 19.444 thoudsand samples per second. This yields an analogue bandwidth of approximately 9.5KHz which is Music Machine was never used for producing sound effects in fact the cutoff frequency of the filters[[:Category:Demos|Demos]].
The clock signal for the ACIA is '''unknown'''. As said above it is based one the same oscillator as used for the ZN449, however, the oscillator is probably ''whatever'' MHz (?) divided by ''whatever'' (?), and its unknown if the ACIA and ZN449 clocks are using the same divider (ie. the ZN449 samples at 19.444kHz, but the ACIA may, or may not, use another frequency). The Music Machine uses NMI interrupt, but it is not clear exactly what it uses it for. All of the devices on The Music Machine data bus are accessible to the Amstrad within its I/O space. ACIA transactions must use 16-bit IO instructions; the converters are accesible via 8-bit IO instructions. {|{{Prettytable|width: 700px; font-size: 2em;}}| ''Port''||''Direction''||''Name''||''Description''|-| F8E8h || Write Only || INTERUPT_SEL| Writing 01 to this port disables internal Amstrad interrupts and replaces the IRQ signal from ACIA. Writing 00 restores normality. ''(Unclear how this works exactly - the description sounds as if uses an [[External Interrupt]] (rather than a [[NMI]]), and as if it does somehow disable the CPC's internal 300Hz interrupt?)''|-| F8ECh || Write only|| ACIA_Control| See [[6850 ACIA chip]] for details|-| F8EDh || Write only || ACIA_Data_write| See [[6850 ACIA chip]] for details|-| F8EEh || Read only || ACIA_Status| See [[6850 ACIA chip]] for details|-| F8EFh || Read only || ACIA_Data_read| See [[6850 ACIA chip]] for details|-| F8F0h || Write only || DAC_WRITE| Data can written to the DAC via this port|-| F8F4h || Read only || ADC_READ| The contents of the A-to-D can be read via this port. Note that the A-to-D must have been startet at least 20uS before this port can be read|-| F8F8h || Strobe || ADC_START| Reading or writing to this port will start analogue to digital conversion|-|} == Pictures == <gallery > caption="The Music Machine"> Image:MusicMachine boxed.JPG| the unit in its box
Image:Music machine 1.jpg|
Image:Music machine 2.jpg|Edge connector missingfemale connector (?)
Image:Music machine back.jpg|Backside
Image:Music machine microphone 1.jpg|The microphone
Image:Music machine microphone 2.jpg|The microphone
Image:Rammusicmashine.jpg|With female connector
</gallery>
<gallery caption== Manual =="The Music Machine Layout, thanks to Jose Leandro"> File:Music Machine - Delante.jpg|The Music Machine - FrontFile:Music Machine - Detras.jpg|The Music Machine - BackFile:Music Machine - Conectores.jpg|The Music Machine - ConnectorsFile:Music Machine - Sin Tapa.jpg|The Music Machine - Without TopFile:Music Machine - PCB Componentes.jpg|The Music Machine - PCB ComponentsFile:Music Machine - PCB Pistas.jpg|The Music Machine - PCB TracksFile:Music Machine - PCB Front.png|The Music Machine - PCB FrontFile:Music Machine - PCB Back.png|The Music Machine - PCB BackFile:Music Machine - Layout.jpg|The Music Machine - Layout
</gallery>
== Tape ==
<gallery> caption="Music Machine">
Image:Music Machine Tape - side B.jpg|Music Machine Tape side B
Image:Music Machine Tape - side A.jpg|Music Machine Tape side A
</gallery>
== Reviews ==
* [[Amstradbladet]] (1987, Issue 9, [[Media:Amstrad Bladet8709022.jpg|Page 22]], and [[Media:Amstrad Bladet8709023.jpg|Page 23]]) (Danish)
* [[Amstrad Computer User]] (March 1987, [[Media:Amstrad Computer User8703 064.jpg|Page 64]], [[Media:Amstrad Computer User8703 065.jpg|Page 65]], and [[Media:Amstrad Computer User8703 066.jpg|Page 66]])
* Review in [[Ε.Π.Τ.Α / Η Ελληνική πλευρά του Amstrad (Greek Side Of Amstrad)]]:
<gallery caption="Review in Greek Side of Amstrad n.6 (May 1987)">
Image:MusicMachine GSOA p1.jpg
Image:MusicMachine GSOA p2.jpg
Image:MusicMachine GSOA p3.jpg
</gallery>
== Advertisements ==
[[image:MusicMachine ACU ad 1987.jpg|thumb|none]]
== Datasheets ==
* [[Media:MC1458.pdf|Datasheet for MC1458]] {{EN}} {{PDF}}
* [[Media:MC 6850.pdf|Datasheet for MC6850]] {{EN}} {{PDF}}
* [[Media:A6850.pdf|Datasheet for ACIA 6850]] {{EN}} {{PDF}}
* [[Media:1983 Ferranti Data Converters.pdf|Datasheet for Ferranti Data Converters]] {{EN}} {{PDF}}
* [[Media:ZN448.pdf|Datasheet for Ferranti ZN448/ZN449]] {{EN}} {{PDF}}
== Manual ==
* [[Media:Music_Machine_Manual.pdf|Music Machine (RAM Electronics) Manual]] {{EN}} {{PDF}}
== Download ==
* [[Media:Music Machine (tape).zip|Music Machine (Tape).zip]] (CDT for Emulators & Exemple on MP3)
* [[Media:Music Machine (Eagle).zip|Music Machine (Eagle).zip]] (Music Machine files for Eagle)
== Weblinks ==
* [http://www.cpc-power.com/index.php?page=detail&num=4329 ''Music Machine'' from CPC-Power]
* [http://cpcrulez.fr/hardware-audio-music_machine.htm ''Music Machine'' from CPCrulez]
* [http://hardware.speccy.org/temp/Amstrad-MusicMachine.html ''Music Machine'' from hardware.speccy.org]
* [http://www.microhobby.com/200903/hard/ram_music_machine.htm ''Music Machine'' from www.microhobby.com]
* [http://www.worldofspectrum.org/hardware/feat17.html Advert for the Music Machine]
* [http://reviews.harmony-central.com/reviews/Keyboard%2FSynth/product/RAM/Music+Machine/10/1 Review]
* [http://www.wacci.org.uk/magazine/136/136_10.html Data transfer via MIDI]
* [http://www.compeng.dit.ie/staff/tscarff/6800/6850acia/6850.htm Information about the Motorola 6850 ACIA]
[[Category:Serial interfaces]] [[Category:Peripherals]] [[Category:Music_and_sound]] [[Category:Manual]]