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Author Topic: hr-16 multiple roms  (Read 3303 times)

windspirit

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hr-16 multiple roms
« on: October 10, 2012, 06:32:22 PM »

Hi!  First post.

I remember seeing a seeing a website that showed how to use multiple soundbanks on a modified HR-16.  Basically you have to solder one ROM pin by pin onto the back of another one except for one pin which is selected by a switch.  This makes it so that the output of the ROMs both go to the same place but the ROM that i being used is switchable, aka 2 sound banks.

I cant seem to find the website now.  I know about burnkits instructions, but for some reason there is no mention of this technique on that site.

Could anyone who knows what im talking about post the link?  Thanks!

~ws
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Gordonjcp

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Re: hr-16 multiple roms
« Reply #1 on: October 10, 2012, 08:24:00 PM »

Another way would be to get the largest capacity 32-pin ROM you can find and concatenate several images together, then use a BCD switch to set the upper address lines.  You might need to fiddle a bit to get a suitable firmware ROM, though.
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Sampler_one

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Re: hr-16 multiple roms
« Reply #2 on: April 28, 2015, 05:29:10 AM »

I am looking for the same thing ! if you find and info can you please msg me..
Ill do the same for you..

regards!
Garry
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Sampler_one

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Re: hr-16 multiple roms
« Reply #3 on: April 29, 2015, 05:32:30 AM »

Here is some info for you.. and others.. I think its right. please correct me if not.. Ill be applying it when my parts arrive..

1 X 28 pin ; P/N 27C256 : OS Eprom
 2 X 32 pin ; P/N 27C040 4 meg: Sound Eproms

can Piggy back with Zif sockets using switch on output enable pins.

Pin 24 output enable - 27C040    with 22k ohm resistor with switch
Pin 22 output enable   - 27C256     with 22k ohm resistor with switch

I have a diagram but I have no idea how to post it here. Let me know.. This might work for now..it's the same idea but not same chip.
http://members.optusnet.com.au/tonymy01/magnavox/piggyback.GIF
« Last Edit: May 01, 2015, 02:24:51 AM by Sampler_one »
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