ACA500 Question regarding Chipmem!

[ElectroBlaster]

Can somebody please confirm that on a bog standard A500 K1.3 Rev.6 wiithout the chipmem mod, that I will only see 512k Chip and the rest as fast with an ACA500?

Unless I add an expansion in the trapdoor to map it as 1mb?
What will happen if I use one of those 2mb boards with the gary adaptor?
Will it still only be 512k and the rest as fast?

My ACA500 has yet to arrive so cant do any testing yet so sorry for all these questions

Wondering now if its a better idea to find an A500+...

 

[roy_bates]

ok,you asked for it.

yes it works on a revision 6 and yes it show 512kb of ram without anything in the expansion bay.

and, a 2mb agnus shows 2mb of chipram not 512kb and the rest fast.

the ones with the gary adaptor the rest of the ram shows as fast.

its up to you if you want to get a 500+,there not exactly hard to get.

and yes if you get a 512kb card for the trapdoor,workbench and avail shows 1mb of chipram.

 

[FOL]

ok,you asked for it.

yes it works on a revision 6 and yes it show 512kb of ram without anything in the expansion bay.

and, a 2mb agnus shows 2mb of chipram not 512kb and the rest fast.

the ones with the gary adaptor the rest of the ram shows as fast.

its up to you if you want to get a 500+,there not exactly hard to get.

and yes if you get a 512kb card for the trapdoor,workbench and avail shows 1mb of chipram.

I get 2mb on a bog standard rev6 using its own is 1.3 / 3.1 KS.

 

[roy_bates]

ok,you asked for it.

yes it works on a revision 6 and yes it show 512kb of ram without anything in the expansion bay.

and, a 2mb agnus shows 2mb of chipram not 512kb and the rest fast.

the ones with the gary adaptor the rest of the ram shows as fast.

its up to you if you want to get a 500+,there not exactly hard to get.

and yes if you get a 512kb card for the trapdoor,workbench and avail shows 1mb of chipram.

I get 2mb on a bog standard rev6 using its own is 1.3 / 3.1 KS.

i dont understand what your saying there fol,a bog standard revision 6 has 512kb of chipram.

or do you mean with the aca?

 

[velourfog]

ACA500 Question regarding Chipmem!

A bog standard A500 rev6 with 512k trapdoor expansion will not get you 1MB chip. It will map as 512k chip + 512k "slow" mem.

To get it mapped as 1MB chip you will need to change a few jumpers on the motherboard, more info is available on Aminet.

Edit: however, IIRC the ACA500 can map the trapdoor RAM as chip for you without the need for changing the jumpers!

 

[BLTCON0]

Edit: however, IIRC the ACA500 can map the trapdoor RAM as chip for you without the need for changing the jumpers!

You can have the trapdoor 512 KB of RAM mapped to $80000 even with the 8371 Agnus (and without using any ACA), that doesn't make it chip RAM though. The Agnus is limited to 512 KB chip RAM addressing and that's what matters.
Loading chip data in that case in the 0.5 - 1 MB segment will be pointless as such addresses written to the hardware registers will have the high-order bit ignored, resulting in transfers in the 0 - 0.5 MB segment = crash. The ACA can't do anything about this.

 

[hgw]

hi,

I have a A500 rev 6a with installed 512kb Ram extension. Sysinfo tells me that there is a Agnus 1Meg. But with using the aca I have already 512kb chipmem can someone tell me what I have to do to get 1Mb chipmem with the aca?

Regards Georg

I checked the board which agnus version are installed and there is a fat agnus 8372a

 

[FOL]

ok,you asked for it.

yes it works on a revision 6 and yes it show 512kb of ram without anything in the expansion bay.

and, a 2mb agnus shows 2mb of chipram not 512kb and the rest fast.

the ones with the gary adaptor the rest of the ram shows as fast.

its up to you if you want to get a 500+,there not exactly hard to get.

and yes if you get a 512kb card for the trapdoor,workbench and avail shows 1mb of chipram.

I get 2mb on a bog standard rev6 using its own is 1.3 / 3.1 KS.

i dont understand what your saying there fol,a bog standard revision 6 has 512kb of chipram.

or do you mean with the aca?

Sorry, yes with ACA but you have to use Kickstart of machine to get full 2mb.

 

[BLTCON0]

hi,

I have a A500 rev 6a with installed 512kb Ram extension. Sysinfo tells me that there is a Agnus 1Meg. But with using the aca I have already 512kb chipmem can someone tell me what I have to do to get 1Mb chipmem with the aca?

Regards Georg

I checked the board which agnus version are installed and there is a fat agnus 8372a

You need to perform the 1 MB chip-RAM mod on the motherboard itself.
Jumper JP2 needs to be changed (this maps the trapdoor RAM to $80000, giving a 1 MB contiguous space for the chip RAM) and jumper JP7A needs to be cut-off (this stops Gary from thinking there's any memory at $C00000).

See this post from Zetr0 as photos speak better than words.

 

[Toni.Wilen]

ACA500 can do it without hardware modifications (Check expert menu, you need flash update if it says "F6 - Reserved" or something like that)

AFAIK there is no official flash update yet available but betas can be downloaded from a1k.org ACA500 thread.

 

[fitzsteve]

I didn't think you needed to perform any hardware modifications and that the ACA500 takes care of it?

 

[BLTCON0]

ACA500 can do it without hardware modifications (Check expert menu, you need flash update if it says "F6 - Reserved" or something like that)

AFAIK there is no official flash update yet available but betas can be downloaded from a1k.org ACA500 thread.

The ACA can obviously take care of JP2 (mapping to $80000), but shouldn't Gary also be told that no $C00000 memory exists?
Or does this become irrelevant in the ACA500 case?

 

[Toni.Wilen]

ACA500 can do it without hardware modifications (Check expert menu, you need flash update if it says "F6 - Reserved" or something like that)

AFAIK there is no official flash update yet available but betas can be downloaded from a1k.org ACA500 thread.

The ACA can obviously take care of JP2 (mapping to $80000), but shouldn't Gary also be told that no $C00000 memory exists?
Or does this become irrelevant in the ACA500 case?

I don't know how it does it in hardware level but it does work, menu has on/off switch to enable/disable it. (Main menu F1/F2 options automatically enable it too if available)

1M chip option is only selectable if chip==512k,agnus==ecs and trapdoor==512k. It can't work if trapdoor has Gary adapter and larger than 512k expansion.

 

[hgw]

on the expert menu the f6 says reserved so I will try a firmware update, thank you for thehint!

can someone tell where I can download the current firmware? I searched the web but did not found anything.....

---------- Post added at 20:21 ---------- Previous post was at 19:55 ----------

found it http://wiki.icomp.de/wiki/File:Menu500_ChipMap.zip

 

[ElectroBlaster]

Ok guys I have just bagged a DKB Megachip so I can take this rev6a to 2mb chip.

Bit dissapointed about not being able to use anything greater than 512kb in the trapdoor!

but I will perform the needed motherboard mods.

Some more questions:

1. Any preference in using an A501 over a little 4-chip expansion I have knocking about?

2. Is there no way at all of using the Zydec Megaboard I have here? it sits in the trapdoor, has a pass-thru for an exisiting 512k upgrade and has a gary adaptor board. Its no reall biggy if that wont work.

3. The DKB will co-exist with the ACA500 + 1220? I hope so

4. Any point in using a kickstart switcher board? I snagged it along with another 2mb trapdoor board. Seller had no clue what the switcher was but included it free of charge! Turns out it has kick1.3 and 2.04 on it

Thank you guys

 

[roy_bates]

1.none
2.no point,you wont get more chipram
3.should do
4.not really

you might have to change denise.

 

[hgw]

success! after I updated the firmware I have 1 mb chipmem

 

[ElectroBlaster]

Thanks

Regarding question 2. I never fully understand how amiga's map memory but its a pita about not being to use it as fast or something? seems a waste to leave it in a box.

But then again the 1220 will lob on 128mb fast and tbh it is a bit ott lol. An a1200 I can understand but an A500... I just want to do it for the sake of it tbh

@hgw. Is that the magic chip ram thing using the 512k in the trapdoor without any mods?

Sucks having to wait for my kit to arrive

Kind just picking at bits at the moment! Got some more refurbing to crack on with. Hoarding old tat pays off! lol... found an old panasonic A500 drive with a broken part. Stashed away in a box I kept a old duffed a1200 panasonic ju that yeilded the part I needed! So that is a win for today

 

[roy_bates]

yeah,sometimes it is worth keeping the old gear.
even if it is just for parts.

 

[hgw]

@ElectroBlaster, jup thats it, after the update the 512k in trapdoor is used as chipmem without any hardware mods