AMITEK HAWK more than 8MB?

ScottC2010 · 01 July 2018, 17:36

Hi,
Is it possible to add more than 8mb to Hawk expansion by modding it?

idrougge · 01 July 2018, 17:43

No.

ScottC2010 · 01 July 2018, 17:44

Thanks

alexh · 02 July 2018, 15:21

It is limited by the CPU which only has 24 address lines (16MiB) and the Amiga chipset + RAM + ROM takes up the other 8MiB

pandy71 · 02 July 2018, 18:42

idrougge is right - easily can't be done but...

...but you could modify autoconfig and add chips on top (piggyback), modify address selection (so efficiently building new expansion) to fit some unused space - some areas are not used and they are reserved - for example memory between $C00000 and $D7FFFF can be legally allocated (so called SLOW FAST) and used also on CPU (FAST) side. Another area is A00000 to BEFFFF (used partially on some systems but mostly not used at all). If i recall correctly somewhere around 13MB+ of RAM can be easily fit within plain A500. Also out of Amiga spec but with some clever design FC0 - FC3 lines can be used to extend address space to 64MB.

watman · 03 July 2018, 10:32

Isn't effective limit of 68k CPU 11,5MB? 2 Chip + 1,5 Slow/Ranger + 8Fast?

pandy71 · 03 July 2018, 12:23

Quote:

Originally Posted by watman

Isn't effective limit of 68k CPU 11,5MB? 2 Chip + 1,5 Slow/Ranger + 8Fast?

Nope - there can be more than 1.5MB slow, and over 1.5MB in other areas normally not used (depends on machine and used extensions).
And 68K allow to address 4x 16MiB (program and data for user and supervisor).

01 July 2018, 17:36	#1
ScottC2010 Registered User Join Date: Apr 2017 Location: Leamington Spa / Warwickshire Posts: 76	AMITEK HAWK more than 8MB? Hi, Is it possible to add more than 8mb to Hawk expansion by modding it?

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Hawk ramboard refuses 8mb ram	Retrofan	support.Other	118	01 April 2019 05:10
[SOLD] AmiTek A1200 Hawk 4Mb/8Mb	Megamix	MarketPlace	2	02 October 2014 15:29
Bought an untested Amitek/Hawk 8MB off eBay...	radiokida	support.Hardware	46	02 May 2013 12:52
For sale on Ebay, Amitek Hawk ram accelerator card with 8 MB simm	miggy1974	MarketPlace	2	14 December 2008 00:42
AMITEK Hawk Ram Board for A1200 for sale	lopos2000	MarketPlace	0	28 April 2005 21:18

01 July 2018, 17:43	#2
idrougge Registered User Join Date: Sep 2007 Location: Stockholm Posts: 3,928	No.

01 July 2018, 17:44	#3
ScottC2010 Registered User Join Date: Apr 2017 Location: Leamington Spa / Warwickshire Posts: 76	Thanks

02 July 2018, 15:21	#4
alexh Thalion Webshrine Join Date: Jan 2004 Location: Oxford Posts: 12,230	It is limited by the CPU which only has 24 address lines (16MiB) and the Amiga chipset + RAM + ROM takes up the other 8MiB

02 July 2018, 18:42	#5
pandy71 Registered User Join Date: Jun 2010 Location: PL Posts: 1,690	idrougge is right - easily can't be done but... ...but you could modify autoconfig and add chips on top (piggyback), modify address selection (so efficiently building new expansion) to fit some unused space - some areas are not used and they are reserved - for example memory between $C00000 and $D7FFFF can be legally allocated (so called SLOW FAST) and used also on CPU (FAST) side. Another area is A00000 to BEFFFF (used partially on some systems but mostly not used at all). If i recall correctly somewhere around 13MB+ of RAM can be easily fit within plain A500. Also out of Amiga spec but with some clever design FC0 - FC3 lines can be used to extend address space to 64MB.

03 July 2018, 10:32	#6
watman Registered User Join Date: Apr 2018 Location: Poland Posts: 36	Isn't effective limit of 68k CPU 11,5MB? 2 Chip + 1,5 Slow/Ranger + 8Fast?

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)