Setting up two A500 for pt-1210

[motosega]

i'm building a Dj setup using akira and hoffman's incredible pt-1210 mod player http://pt1210.kikencorp.com/

i've already been djing for while, so i have a mixer, audio cables etc.

it just happened that i got my hands on two Amiga 500s at the same time that i heard about pt-1210
i instantly decided that i had to get them up and running with pt1210.


i want to do everything as cheaply as i can and i've got a bit of electronics experience, so i will be doing everything possible by Diy,


back in the day i had an atari st, so i missed out on a lot of amiga info. but i did some hardware mods (overscan, diy 4mb ram etc.) so i'm not a total stranger in the land of 68k.

the first thing i did when i got the a500 was build a serial null modem cable and install amiga explorer in an xp VM.
so i've been doing a crash course in workbench1.3 and finding all the quirks of the amiga. Some things are amazing(command line history! yay!) others are insane(the disconnect between what you see in workbench and what is on the disk)

i've been lurking here for about a week sucking up info but i'd still like run my plans by the forum and see what i might have missed.

so i have two A500s with rev6a boards. they currently have only 512k ram, but i will be updating them to 1mb chipram by soldering chips onto the board. (i have already ordered chips)

i still can't figure out if its still possible to add a trapdoor ram expansion with 1mb chip ram on board. if this is the case i'll be making trapdoor ram boards too. probably from scavenged simms.

to get the A500 running with pt1210 i will have to update the kickstarter to 2.04 or 3.1 i don't think it really matters which (again i have chips on the way.)

after remembering that floppies are an absolute pain, for storage i have ordered gotek floppy emulators (not sure which firmware i will use yet.)

but i'm already wondering if i should build CF/ide interfaces.
is there a way to get a bare pcb for CFIDE86K? or any similar projects i might have missed?

for screens i'll be using cheap lcds for car reversing cameras, they cost less than 20€ on ebay., i'll probably just use the monochrome composite output from the A500 unless theres an easy way to get colour without the massive adapter.

for powersupplies, i don't know if its better to use the original amiga power supplies ( i have one heavy one and one light one) or use a couple of atx power suppliesi have lying arround. i'm going for reliability more than authenticity.

the only other thing i can think of is that one of the a500s have a bad keyboard membrane, the keys 1 Q A Z and Left Amiga, don't work, i've given it a clean with isopropy alcohol, but no improvement, next i will try to fix it with conductive paint.

[Jope]

Originally Posted by motosega

i still can't figure out if its still possible to add a trapdoor ram expansion with 1mb chip ram on board. if this is the case i'll be making trapdoor ram boards too. probably from scavenged simms.

It is possible, don't install the chips to the motherboard, use this instead
http://eab.abime.net/showthread.php?t=85395 (better read the whole thread)

after remembering that floppies are an absolute pain, for storage i have ordered gotek floppy emulators (not sure which firmware i will use yet.)

HxC or FlashFloppy.

but i'm already wondering if i should build CF/ide interfaces.
is there a way to get a bare pcb for CFIDE86K? or any similar projects i might have missed?

MKL's site has all the info you need. http://mkl211015.altervista.org/ide/ide68k.html

for screens i'll be using cheap lcds for car reversing cameras, they cost less than 20€ on ebay., i'll probably just use the monochrome composite output from the A500 unless theres an easy way to get colour without the massive adapter.

I think someone on A1k made a video hybrid "vidiot" with colour composite.

for powersupplies, i don't know if its better to use the original amiga power supplies ( i have one heavy one and one light one) or use a couple of atx power suppliesi have lying arround. i'm going for reliability more than authenticity.

ATX is fine if it has all the voltages. Don't go overboard with the watts.

the only other thing i can think of is that one of the a500s have a bad keyboard membrane, the keys 1 Q A Z and Left Amiga, don't work, i've given it a clean with isopropy alcohol, but no improvement, next i will try to fix it with conductive paint.

If all else fails, you can get reproduction membranes from RWAP software. By all means try the conductive paint fix first.

[motosega]

thanks,

glad to know i'm not far from the right path...

[daxb]

I would say A500 is not a good choice. If you want it small then A600 otherwise A1200. CF to IDE Adapter and then you only need to anoy with display problem.

[motosega]

Originally Posted by daxb

I would say A500 is not a good choice. If you want it small then A600 otherwise A1200. CF to IDE Adapter and then you only need to anoy with display problem.

i think you're definatly right, A600s would be better. smaller, easy CF card solutions and an already compatible kickstart.

but i already have two a500s. which came from a Dj friend, at no cost to me. i think i'll do it anyway. i think i that by DIYing everything i can get them up to spec and spend less than it would cost to buy two A600s from ebay.

i already have all stuff i will need, for soldering, flashing firmware in the gotek, burning roms etc. so my total outlay is about 50€ unless i built ideCFs then i might go up to to about 120€ which still won't get me an A600 on fleabay.


hey if i wanted an easy life i'd just render the mods as mp3s and play them in a cdj!

[ElectroBlaster]

You know what!

Two A500's would be a blast for pure retro vibe, many people still identify with the A500 as they had one when younger, more than likely their first Amiga back in the day.

Then think about what music was created and actually pressed onto vynil!

Dex and Jonesey and Urbanshakedown being to instantly obvious ones that stand out.

I would even go to the lengths of A1200 boards in A500 cases if I was so inclined lol, but that is alot of work.

[Amiga1992]

Hey welcome to the forums! I think you messaged me through the PT-1210 FB page. Here you are bound to get more feedback from more people so it's better

Yeah the main issue with the A500s is they are a big clunk of shit. Really large.
And currently, the kickstart compatibility I wish we'd get rid of sooner...

But otherwise, I would recommend an A500. It's built like a tank and easy to service at home. I used to hate them, but now that I spent some time with one, this fact alone makes it super convenient, repairs are easy and this is key in this hobby. Would also be pretty durable if you actually gig with them often (I am probably the only person ever worried about this kind of thing though).

A600 have sadly gone way up in price when Vampire got released, so you can't find them cheaply anymore. Makes me glad I got my DJ ones before that happened, I paid very little for them.


In any case good luck! And let me know if you run into any issues.

[motosega]

Originally Posted by Akira

Hey welcome to the forums! I think you messaged me through the PT-1210 FB page. Here you are bound to get more feedback from more people so it's better

Yeah the main issue with the A500s is they are a big clunk of shit. Really large.
And currently, the kickstart compatibility I wish we'd get rid of sooner...

But otherwise, I would recommend an A500. It's built like a tank and easy to service at home. I used to hate them, but now that I spent some time with one, this fact alone makes it super convenient, repairs are easy and this is key in this hobby. Would also be pretty durable if you actually gig with them often (I am probably the only person ever worried about this kind of thing though).

A600 have sadly gone way up in price when Vampire got released, so you can't find them cheaply anymore. Makes me glad I got my DJ ones before that happened, I paid very little for them.


In any case good luck! And let me know if you run into any issues.

Hi akira,

yep, thats me.

i've got some waiting to do before my parts arrive, so in the meantime i'm reading everything i can and playing with 8-bit bubsys wonderful protracker2.3d clone on my mac.

even though they are massive, the A500s are still smaller and lighter than the numark ttx vinyl turntables i normally carry to gigs...unfortunatly i don't think its practical to replace them with a pair of amigas though, i'll probably end up loading both into the car...

yep, looking inside these 500s i can see they are bombproof and easily fixable.


i'm wondering how much having only 1mb of chip ram will be a limit, are there many good mods with more than 1mb of samples?

does pt1210 load itself into chip ram or will it load itself into slow ram and leave the chip ram for samples?

the problems with kickstarter 1.3 are a pain but its not a deal breaker for me, upgrading the rom isn't a problem. i quite like the idea of making custom rom images too.

[daxb]

Originally Posted by motosega

i'm wondering how much having only 1mb of chip ram will be a limit, are there many good mods with more than 1mb of samples?

Not many. The most should fit into 1MB but you will have less chipram free then 1MB. Akira can tell you how much mem is free or used by pt1210.

[motosega]

in fs-uae pt1210 gives me 880k free chip ram when configured as a 500 with kickstart 1.3

I must try again with 1mb chip and 512k slow ram.

[Amiga1992]

Originally Posted by motosega

unfortunatly i don't think its practical to replace them with a pair of amigas though, i'll probably end up loading both into the car...

Try inserting one Amiga into the mix first, or 1 tt+ 1 A500. Mix it up!

does pt1210 load itself into chip ram or will it load itself into slow ram and leave the chip ram for samples?

You know I have not tried, because my A500 has 1.3 in it. I dunno how it would "see" "slow" RAM. When you have Fast RAM, PT-1210 will load itself there and leave all your Chip RAM free. I am guessing your extra 0.5MB of RAM will be considered in the same way and PT-1210 will sit itself there.

1MB is plenty for a lot of modules, only the more modern ones would require you having 2MB of RAM! I can count with the fingers of my hands how many tunes are over 1000KB. Probably some of h0ffman's latest are most of them. Everything oldschool, like from the 90s, will probably happily fit on a 1MB machine.

If a 1MB setup leaves you with 880KB of free RAM, that's a whole diskette! Not many tunes would have filled up that much space back then.
It makes sense, PT-1210's executable is less than 200KB if I am not wrong.

[idrougge]

How do you get 1 MB of chip RAM in combination with 512 kB of slow RAM?

[motosega]

Originally Posted by idrougge

How do you get 1 MB of chip RAM in combination with 512 kB of slow RAM?

see this thread over at the hardware mods sub forum http://eab.abime.net/showthread.php?t=85395

with an adapter on the gary chip garry its possible to add more chip ram And more slow ram.

[motosega]

Originally Posted by Akira

Try inserting one Amiga into the mix first, or 1 tt+ 1 A500. Mix it up!

i'll either get a 4 channel mixer, or another 2 channel battle mixer and set them up next to each other. i like using doubles (same track on both decks) for beat juggling and effects like echoing(play one deck slightly behind the other turn the volume down on that deck, instant echo!) flanging(just play the two decks at exactly the same time, you can adjust the flange effect on turntables by touching the sticker, on pt1210, you could just nudge the pitch bend.)

most places i play aren't the traditional clubs with tiny booths, i normaly get a big table all to myself.

1MB is plenty for a lot of modules, only the more modern ones would require you having 2MB of RAM! I can count with the fingers of my hands how many tunes are over 1000KB. Probably some of h0ffman's latest are most of them. Everything oldschool, like from the 90s, will probably happily fit on a 1MB machine.

i'm quite into the modern stuff though..

If a 1MB setup leaves you with 880KB of free RAM, that's a whole diskette! Not many tunes would have filled up that much space back then.
It makes sense, PT-1210's executable is less than 200KB if I am not wrong.

i turns out i was wrong about how much free ram.

testing pt1210 with fs-uae with kb1.3 i get:

512k chip ram = 185k free

512k chip + 512k slow = 350k free

1mb chip ram = 697k free

1mb chip + 512k slow = 862k free
1mb chip + 1mb slow =862k free
1mb chip + 1.5mb slow = 862k free


it looks like it does indeed relocate into slow ram!

[Amiga1992]

Originally Posted by motosega

i'm quite into the modern stuff though..

There 's not much of that being produced, maybe three tunes a year?
At least of what's released publicly.

it looks like it does indeed relocate into slow ram!

Yeah as It hought, slow RAM IS "Fast" RAM, so PT-1210 would locate itself there first.

So you should really look, if you want 2MB chip, into getting an upgraded Agnus chip, so you can have 2MB Chip.

This is again the point whee I question going through all the trouble to expand two A500

[motosega]

Originally Posted by Akira

There 's not much of that being produced, maybe three tunes a year?
At least of what's released publicly.

it's going to take a long time to listen to the whole of modarchive ftp as it is...

So you should really look, if you want 2MB chip, into getting an upgraded Agnus chip, so you can have 2MB Chip.

i don't think i want 2mb chip that badly..

This is again the point whee I question going through all the trouble to expand two A500

i know......



any idea what takes up that missing ~200kb chip ram? is it graphics? os stuff?
i thought pt-1210 was supposed to kill the system.

maybe i could free some chip Ram up by modifying the kickstart rom.

[Amiga1992]

Originally Posted by motosega

any idea what takes up that missing ~200kb chip ram? is it graphics? os stuff?
i thought pt-1210 was supposed to kill the system.

What "missing" RAM? You mean whatever there is from 1MB to 862k? It's eaten up by system stuff, for example the hard drive partition being mounted.

This is a fresh startup for me with nothing loaded, look at the RAM:


I have 875984 bytes available on a fresh boot.
My system has one hard drive partition, but WinUAE "folders as HD" method eats up much less RAM than a real hard drive, so I am being lucky.
On the above setup, after running, PT-1210 has this much RAM available:

PT-1210 executable itself is 169780 bytes in size. That's 706204 left. There's other stuff that takes place in RAM, like the folder file list. I have no idea how much that is taking though. And more. With all this I just mean, that the available RAM is clear, there's nothing "missing". It makes sense what you show, and PT-1210 as I said will take about 200KB of RAM alone (apparently it's taking about 221KB in this setup I just tested)

PT-1210 "kills" the system, but that doesn't mean by doing so it suddenly has all RAM available. The Amiga needs stuff to run that must reside in RAM. PT-1210 needs stuff from the Amiga system methods to run.

Also whatever graphic assets the program has, MUST reside in Chip RAM. This is because of how the Amiga architecture works.

I understand you want the A500 to work as is, but then you will have to live with ~650KB RAM available for modules. Again, 650KB is a lot for modules.

Editing a Kickstart ROM won't let you ease up on RAM easily. Also you need to know really well what you are doing.
You're beating a dead horse, you either work with the Amiga limitations, or not, there's no way around it.

[motosega]

thanks for you in depth reply, it filled in a few blanks.

i did some more testing in fs-uae:

it turn out that almost all of that ram was being used by the system is the second floppy drive.

with ks 3.1with 1mb chip only and one floppy drive i get 721k free.

Finally with ks 3.1 with 1mb chip and 1mb slow and only one floppy there are 926k free! not at all shabby!
thats almost all the chip ram free! the system only needs 98k chip ram.

i know, i'm flogging a dead horse. i think it's really dead now.

as for modifying kickstart, i just read the docs for romsplit/remus and like you said theres very little in kickstart that can be taken out. initialy i thought that the ide drivers were much bigger than they actually are.

[Amiga1992]

Yeah the OS is really tight and optimized, I don't think you can avoid the footprint, it's really low already.
926KB free is a shit ton of RAM! I would be happy with that.
Then again if you are running just from floppy, what are you gonna have, one huge tune per floppy? You'll hate the experience soon, especially after the disks start bit-rotting :P

Because for tiny tunes, 600+ KB was more than enough.

[daxb]

Loading modules from floppy would be a nice mixing experiences. On the other hand if the audience can see the loading error on big screen you will rock the party.