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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: tonata on May 05, 2020, 04:50:29 PM

Title: Amiga trapdoor memory detection
Post by: tonata on May 05, 2020, 04:50:29 PM

Hi,

I am new to the Amiga. I have recently acquired an AMIGA 500 with Workbench 1.3.
It has a trapdoor expansion RAM which is refereed as "slow memory". I did replaced the battery, but now I am not sure the expansion RAM is detected anymore. Leander game halts once it says "Expansion Memory detected".

Which program does show the amount of slow memory? I am not sure how to interpret the results from sysinfo program.

Title: Re: Amiga trapdoor memory detection
Post by: TribbleSmasher on May 05, 2020, 04:54:29 PM

If you run the 'Shell' command line from your Workbench disk you can enter the 'Avail' command. it will most likely tell you around 1Meg of total memory.

Title: Re: Amiga trapdoor memory detection
Post by: tonata on May 05, 2020, 05:05:09 PM

I says for "total":

Available: 835520
In-use: 204600
Maximum: 1040120
Largest: 440832

"Maximum" is maximum installed or maximum that could be installed in general on Amiga 500 ?

Thanks

Title: Re: Amiga trapdoor memory detection
Post by: TribbleSmasher on May 05, 2020, 05:08:03 PM

Maximum is largest you could have without loading Workbench, in your case 1Meg (probably 512kB +512kB installed). This avail cmd is rather old, if you check with Sysinfo memory page what does it say?

Title: Re: Amiga trapdoor memory detection
Post by: tonata on May 05, 2020, 05:27:26 PM

It says similar.

Page 1:

total size: 506 kb
Memory type: SLOW RAM PUBLIC
Node name: Fast Memory

Page 2:

total size: 512 kb
Memory type: CHIP RAM PUBLIC
Node name: Chip Memory

How much fast memory does an Amiga 500 has without an expansion? And how much it was added in my case?

Title: Re: Amiga trapdoor memory detection
Post by: TribbleSmasher on May 05, 2020, 05:29:38 PM

It has only Chip RAM in its original configuration.

http://amiga.resource.cx/mod/a500.html

Title: Re: Amiga trapdoor memory detection
Post by: tonata on May 05, 2020, 06:11:53 PM

So the fact that I have 506 kb Fast Memory which is actually "Slow Memory" means the expansion works correctly ?

Title: Re: Amiga trapdoor memory detection
Post by: TribbleSmasher on May 05, 2020, 06:25:33 PM

Yes.
Also, try to set date and time and check if it is remembered after switching the Amiga off for some 30 minutes or so.
Can you have a look at the expansion? If it has an unopened metal case you should consider open it up to remove the leaking Varta battery from hell.

Title: Re: Amiga trapdoor memory detection
Post by: tonata on May 05, 2020, 06:40:49 PM

Thanks!!!

I already replaced the battery with a button one. The thing is that I was afraid that I could have done something wrong. RTC works fine but this was no indication if the RAM was also OK.

Title: Re: Amiga trapdoor memory detection
Post by: TribbleSmasher on May 05, 2020, 06:43:58 PM

Well it seems okay. To actually check the RAM you would need to run tests.