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The Amdrum is an 8bit D/A converter (hardware) with drumkit (software), made by the British company [[Cheetah]].

Quality of the playback was nice, considering the time and price. The drumkit samples were read from the suplied tapes. There were serveral tapes with different themes. Along with the Amdrum came a sequencing program. It was able possible to play 8bit sound copy the samplesto disc, but the sequencing program had to be patched! Amdrum was probably Cheetahs version of the SpecDrum (As revealed on the PCB "AMSTRAD SPECDRUM"). Aside of Cheetahs own sequencer you can use some commands of the RSX ROM for [[LambdaSpeak III ROM|LambdaSpeak III]] to use the Amdrum.

Quality Now, thanks to Jose Leandro, the hardware specialist of the playback was nicespectrum, considering the time and price.with his famous page:

The samples was read from the suplied tapeshttp://trastero.speccy.org/cosas/JL/JL.htm

There was serveral tapes with different themes!We can know more about this hardware.

Amdrum was probably Cheetahs version of the SpecDrum * Uses I/O Port FFxxh (As revealed on the PCB "AMSTRAD SPECDRUM"Write only), ie. only /IORQ, /WR, A15-A8 are decoded. A7..A0 are not decoded, and /RD isn't used, too.* Port usage: Write 8bit unsigned sample data to Port FFxxh. The D/A converter is mono and has only one channel (mixing multiple channels is to be done by software).No CPC emulator supports * After booting, the Amdrumsoftware first sets port [FF80h]=80h. To hear 'Emulators can use that feature to detect Amdrum' in action software - and, after [FF80h]=80h was detected, map the Spectrum emulator Spectaculator emulates whole range of ports FF00h..FFFFh to the SpecDrumAmdrum.  No other * During operation, the Amdrum software than Cheetahs own sequencer uses port FFxxh. Where "xx" is know to use garbage coming from the AmdrumAmdrums keyboard scanning routine (see disassembly below). == Technical Specifications ==

The PCB(oneside) contains five chipson the single-sided PCB are:

|74LS30N||Single 8-input NAND||Port decoding , /ADDR_MATCH=LOW when A8..A15 all HIGH

|74LS32N||Quad 2-input OR||Port decoding, /DAC_WRITE when /ADDR_MATCH, /IORQ, /WR all LOW

|SN74LS04N||?Hex Inverters||Charge pump circuit, used to create negative voltage rail for the op amp

|064C0PTL064CDP||Quad Operational Amplifier?||Buffer and low pass filter

|Ferranti ZN428E-8||8bit DAC||mono one-channel 8bit D/A converter (unsigned samples)

The Amdrum probably uses port #FF50 I* [[Media:ZN428.pdf|ZN428 Datasheet]] - 8bit D/O, needs to be confirmed thoughA Converter* [[Media:TL064.pdf|TL064 Datasheet]] - Quad Amplifier

[[Media:ZN428.pdf|Datasheet == Partial dissassembly of the ZN428player == exx ld a,(bc) ;get channel 1 add a,(hl) ;add channel 2 ex de,hl add a,(hl) ;add channel 3 inc hl ex de,hl inc bc add a,80h ;add bias (signed to unsigned) inc hl exx out (c),a ;out [FFxxh]with C=whatever ld b,0f6h in a,(c) ld c,a ;C=PIO Port C (keyb row, tape, psg control) xor 05h ;five ??? out (c),a ld a,0f4h in a,(66h) ld (404eh),a out (c),c ... ;something missing here? ld b,0ffh nop nop nop exx ld a,(bc) ;get channel 1 add a,(hl) ;add channel 2 ex de,hl add a,(hl) ;add channel 3 inc hl ex de,hl inc bc add a,80h ;add bias (signed to unsigned) inc hl exx out (c),a ;out [FFxxh]with xx=garbage (above PIO Port C value)

== Kits Pictures ==

<gallery caption=== Afro Kit Covertape ==="AMDRUM">

<gallery caption="Afro Kit Covertape - Instructions"> Image:Afro Kit 1Amdrum_1.jpg|Afro Kit CovertapeBoxImage:Afro Kit 2Amdrum_2.jpg|Afro Kit InstructionsAmdrum inside boxImage:Afro Kit ErrataAmdrum screen shot 1.jpggif|Screen shotImage:Amdrum screen shot 2.gif|Afro Kit ErrataScreen shot

<gallery caption=== Electro Kit Covertape ==="300dpi scans by Robcfg">

Image</gallery> <gallery caption="Amdrum Layout, thanks to Jose Leandro"> File:Electro Kit 1Amdrum - interface_delante.jpg|Electro Kit CovertapeAmdrum - Front BoxImageFile:Electro Kit 2Amdrum - interface_detras.jpg|Electro Kit InstructionsAmdrum - Back BoxFile:Amdrum - cara_componentes.jpg|Amdrum - ComponentsFile:Amdrum - cara_pistas.jpg|Amdrum - TracksFile:Amdrum PCB.png|Amdrum - PCB FrontFile:Amdrum Layout.png|Amdrum - Layout

=== Latin Kit Covertape =Reviews / Commercials ==

<gallery caption="Latin Kit Covertape - InstructionsCommercials for the Amdrum">

Image:Latin Kit 1amdrum commercial.jpg|Latin Kit CovertapeCommercial for AmdrumImage:Latin Kit 2Amstrad Computer User8610028.jpg|Latin Kit InstructionsReview of the Amdrum in [[Amstrad Computer User]]Image:Amstrad Computer User8610029.jpgImage:Amstrad Computer User8610030.jpg

== Tapes == === Amdrum Tape ===

=== Afro Kit Tape =Kits ==

{| class="wikitable sortable" style="width:100%"|''Title''||''Front Covertape''||''Back Covertape''||''Tape Side A''||''Tape Side B''|-|[[Afro Kit]]||[[Image:Afro Kit 1.jpg|120px]]||[[Image:Afro Kit 2.jpg|120px]]||[[Image:Afro Kit Tape A.jpg|120px]]||[[Image:Afro Kit Tape side AB.jpg|120px]]|-|[[Electro Kit]]||[[Image:Afro Electro Kit 1.jpg|120px]]||[[Image:Electro Kit 2.jpg|120px]]||[[Image:Electro Kit Tape A.jpg|120px]]||[[Image:Electro Kit Tape B.jpg|Afro 120px]]|-|[[Latin Kit]]||[[Image:Latin Kit 1.jpg|120px]]||[[Image:Latin Kit 2.jpg|120px]]||[[Image:Latin Kit Tape A.jpg|120px]]||[[Image:Latin Kit Tape side B.jpg|120px]]|-|}

</gallerycaption="Afro Kit - Errata">

=== Electro Image:Afro Kit Tape ===Errata.jpg|Afro Kit Errata

</gallery caption="Electro Kit Tape">

=== Latin Kit Tape =Videos ==

Image{{#ev:Latin Kit Tape A.jpgyoutube|Latin Kit Tape side AImage:Latin Kit Tape B.jpg0z-jGDOzwGQ|Latin Kit Tape side B400}}

== Pictures == <gallery caption="AMDRUM">Image{{#ev:Amdrum1.jpgyoutube|Image:Amdrum2.jpg|Image:Amdrum inside1.jpg|Component sideImage:Amdrum inside2.jpg|"AMSTRAD SPECDRUM"Image:Amdrum screen shot 1.gif|Screen shotImage:Amdrum screen shot 2.gif|Screen shotImage:Amdrum_1.jpg|BoxImage:Amdrum_2.jpgm6R_W9CZWGU|Amdrum inside box</gallery>400}}

* [[Media:Amdrum Manual.pdf|Amdrum Manual]] (pdfCheetah) == Reviews / Commercials == <gallery caption="Commercials for the Amdrum">Image:amdrum commercial.jpg|Commercial for AmdrumImage:Amstrad Computer User8610028.jpg|Review of the Amdrum in [[Amstrad Computer UserManual]]Image:Amstrad Computer User8610029.jpgImage:Amstrad Computer User8610030.jpg</gallery> == Weblinks == [http://www.engadget.com/2005/10/28/music-thing-the-zx-spectrum-specdrum-module/ Site about the SpecDrum] [http://www.crashonline.org.uk/27/specdrum.htm Review of the Spectrum version] [http://www.worldofspectrum.org/hardware/feat42.html Another review] == Other playback devices == [[Music Machine]],[[Digiblaster]] == Videos == A presentation(from around 1985) of the ZX Spectrum version of the Amdrum(Specdrum), also mention of the upcomming Amstrad CPC version {{#ev:youtube|m6R_W9CZWGU|200EN}} {{PDF}}

* [[CategoryMedia:HardwareAmdrum (Eagle).zip|Amdrum (Eagle).zip]] (Amdrum files for Eagle) == Weblinks == * [http://www.cpc-power.com/index.php?page=detail&num=4294 ''Amdrum'' from CPC-Power]* [http://www.cpc-power.com/index.php?page=detail&num=4312 ''Amdrum Afro kit'' from CPC-Power]* [http://www.cpc-power.com/index.php?page=detail&num=4313 ''Amdrum Electro kit'' from CPC-Power]* [http://www.cpc-power.com/index.php?page=detail&num=4311 ''Amdrum Latin kit'' from CPC-Power]* [https://cpcrulez.fr/hardware-audio-amdrum_AA.htm ''Amdrum'' from CPCrulez]* [http://hardware.speccy.org/temp/Amstrad-Amdrum.html ''Amdrum'' from hardware.speccy.org]* [http://www.engadget.com/2005/10/28/music-thing-the-zx-spectrum-specdrum-module/ Site about the SpecDrum]* [http://www.crashonline.org.uk/27/specdrum.htm Review of the Spectrum version]* [http://www.worldofspectrum.org/hardware/feat42.html Another Spectrum review] [[Category:Peripherals]] [[Category:Music and sound]] [[Category:Manual]][[Category:Video contents]]