Help Identifying Expansion card required

[coutram]

All,

Hope you can help me here, I'm pretty sure this is from an Amiga 500.

Details are: Stamped on back - Ashcom

Chip numbers: 4x P21014-10 & 1x 8736BF

Done a load of googling and I think the P21014 chips are 512k each, which would give 2mb total. http://www.datasheetarchive.com/shortform-datasheet/P21014-10.html

Also, any ideas what it might be worth?




[edit]
Sadly, we cannot offer any valuations on AmiBay, please take some time to have a read of the rules and guidelines - it will explain in detail why we cannot give such advice and why price comments are not allowed here. Z

 

[skagon]

Probably a 512k RAM expansion, with an empty socket and holes for a real-time clock chip and battery.
Probably one of the most common pieces of hardware for an Amiga 500.

 

[coutram]

Thanks, not sure it is a 512k expansion though, the chips appear to be 256k each:
http://www.datasheetarchive.com/shortform-datasheet/P21014-10.html

 

[Justin]

yep looks like an A500 512k trapdoor ram expansion.

and no one here can tell you a price as it is against the sites rules, which are here https://www.amibay.com/misc.php?do=cfrules btw

 

[Zetr0]

Thanks, not sure it is a 512k expansion though, the chips appear to be 256k each:
http://www.datasheetarchive.com/shortform-datasheet/P21014-10.html

Yes, this type of marking can be a bit of a confusion - while the chips are 256k in cells they are only 4 bits wide.

With 4 of these chips that gives you 16bits wide at 256k = 512KB or 0.5MB

I hope that helps.

 

[rkauer]

This one seems a bit different from yours, but they are all the same.

The 21014 is a common 256k x4 chip. In group of four they will give the Amiga 512kb of extra RAM as Ranger Mem (C8000 address, the infamous pseudo-FAST RAM) or, modifying the Amiga motherboard a bit and using a 8372A Agnus will bring the chip RAM to full 1Mb.

 

[Justin]

didn't we already answer this?

https://www.amibay.com/showthread.php?t=51400

and no-one on this site can tell you a priceoh:

 

[skagon]

I think he wants to prove it's a 2meg board; refuses to believe it's a 512k...
For the record, I've got an 8meg board (IIRC), and it looks like an aircraft carrier. Takes up the whole available space; in fact, it can only be installed from the inside -- you have to unscrew the case -- since it doesn't even fit the trapdoor. And it's got an extra board that goes between Gary (IIRC) and the main board, since the trapdoor connector can only address 512k -- it's only got 9 address lines. A 2meg board would pretty much need the same.
Sorry mate.

 

[Zetr0]

didn't we already answer this?

https://www.amibay.com/showthread.php?t=51400

and no-one on this site can tell you a priceoh:

Well if thats the case I think I shall save some time and quote ME ^_^

Thanks, not sure it is a 512k expansion though, the chips appear to be 256k each:
http://www.datasheetarchive.com/shortform-datasheet/P21014-10.html

Yes, this type of marking can be a bit of a confusion - while the chips are 256k in cells they are only 4 bits wide.

With 4 of these chips that gives you 16bits wide at 256k = 512KB or 0.5MB

I hope that helps.

 

[coutram]

Great, thanks for all the help guys. That clears it up nicely!

 

[coutram]

And sorry, managed to post a duplicate thread!

 

[Bryce]

Despite the fact that it didn't have the RTC and battery installed, it looks like something still managed to leak onto it. The connector pins on the left have been corroded by something acidic.

Bryce.

 

[SaviorX]

the confusion derives from the fact that it is described as holding 256k 'words' per chip...this is mistaken as being the same as '256KB', which it is not....as Zetro has explained (somewhat)

256k = 256,000 and @ 4bits.... (ie: 256,000 4-bit 'cells')

well...8bits to a byte = 128KB per chip.

 

[Zetr0]

^^^ this guys knows his stuff



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