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Old 25 February 2019, 21:22   #2061
Casper
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In modern day hardware it's my understanding all memory lanes have to be equal length, did the Amiga ever have something similar where some lanes had to be of equal length?
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Old 26 February 2019, 14:21   #2062
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Short answer: Not so much. The traces being the same length is more of a requirement with higher speeds, and the Amiga speeds are generally too low to matter. You'd need traces longer than the motherboard to really make a significant difference.

Longer answer: Essentially, trace length has two main factors to be considered: impedance and propagation time. Impedance is how difficult it is to change a signal on a given trace (so a 0 to a 1 or 1 to a 0 in digital terms), and this changes with the length of the trace and other factors, such as other traces nearby, ground planes, width of the trace and so on. This is something that needs to be managed more tightly at higher speeds and tighter tolerances, but in general, the difference between lengths of traces would have to be much greater to have a significant effect at the low speeds of an Amiga memory bus.

Propagation time is the length of time it takes for a change at one end of the trace to take effect at the other end of the trace, effectively how long it takes the signal to travel the length of the trace. For lower speed stuff, this speed can be assumed to be infinite (i.e., zero propagation time), as the speed is so high (maybe half the speed of light) that the short distances across an Amiga motherboard mean propagation times are miniscule compared to the reaction times of the chips dealing with the signals. Modern RAM (and other computer components - controllers, north and south bridges, CPUs etc.) can react so quickly that these things do actually matter, and trace length starts to become a genuine factor, since any traces that are longer than others will mean the bit on that trace arriving slightly later than the other traces. You really need to get to the GHz range for that to have a significant effect, which is why PC motherboards are full of squiggly traces in order to keep bus lengths equal.

It's also one of the reasons most peripherals are now serially bussed - trace lengths are far less critical, meaning speeds can be increased dramatically once the chips at either end can handle it. PCI Express, SATA, USB, Thunderbolt etc. all take advantage of this extra flexibility and simplicity of design.
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Old 26 February 2019, 19:35   #2063
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Thank you very much Daedalus for the detailed explanation, it's much appreciated.
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Old 26 February 2019, 22:38   #2064
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**snip**
Lovely!
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Old 01 March 2019, 12:06   #2065
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2 questions at this moment in time.

1. What is the best way to connect wifi so I can use a browser like Ibrowse/Aweb (not BBS). Heard there are plenty of issues with wifi networking and best to go ethernet, that sadly is not an option for me due to location of amiga! Seems like you need a specific wireless cards that are correctly set up and flashed. If I do see these types of card they are always out of stock. Feel pretty dumb asking this tbh


2. What the hell is going on with Cloanto / Hyperion? Why the bitterness and talk of lawsuits, this isn't in the spirit of Amiga and damaging the scene. Guess I really don't understand what the hell is going on there, Im overjoyed a new os is out for 68k, whether its perfect or not, seems like this is not a view shared by all.
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Old 01 March 2019, 12:21   #2066
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Being negative, often to the point of trolling, is a pretty common pastime in Amigaland for quite a number of people. I guess it makes them feel better about their own lives in some twisted fashion.
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Old 01 March 2019, 14:48   #2067
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2 questions at this moment in time.

1. What is the best way to connect wifi so I can use a browser like Ibrowse/Aweb (not BBS). Heard there are plenty of issues with wifi networking and best to go ethernet, that sadly is not an option for me due to location of amiga! Seems like you need a specific wireless cards that are correctly set up and flashed. If I do see these types of card they are always out of stock. Feel pretty dumb asking this tbh
Suitable cards are popular, and won't be out of stock for very long, so keep an eye out for them. Keep an eye on retroready.one for them to show up again, or even message Sir_Lucas on here and ask him when he might have some available again. Failing that, an ethernet card and some powerline adaptors might be suitable, though I've never been particularly happy with the fragility of ethernet PCMCIA adaptors.


Quote:
2. What the hell is going on with Cloanto / Hyperion? Why the bitterness and talk of lawsuits, this isn't in the spirit of Amiga and damaging the scene. Guess I really don't understand what the hell is going on there, Im overjoyed a new os is out for 68k, whether its perfect or not, seems like this is not a view shared by all.
It might not be the original spirit of the Amiga, but it's been par for the course in the Amiga world for well over a decade now. What's left of Amiga is a shady-at-best shell that exists purely to live off the name. This arrangement means that companies who get involved can never be fully sure of where they stand, resulting in legal disputes that serve to do little other than strangle further development by acting as a money sump.

Alongside this, there are the rabid fans for whom the almost religious fervour for or against a particular product, company or approach is more important than enjoying the hobby, which serves to magnify the impact of the legal wranglings and spread toxicity and division throughout what's left of the Amiga community.

There are plenty of details out there on the specifics of the various lawsuits over time, though you'll find it difficult to get an unbiased view of the situation from forum posts and social media. Best to bear that in mind and take as objective a view as you can to avoid getting bogged down in speculation, emotion and trolling if you go tugging on that particular thread.
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Old 02 March 2019, 00:45   #2068
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many thanks for the detailed reply Daedalus, will be patient and keep an eye out for wifi cards. thought about powerline adapters to but have no free wall socket either ha!

in regards to the legal battles, you make perfect sense there. its difficult to accept that the Amiga brand is just a name that is being plucked apart like chicken. i think cloanto and hyperion can co-exist happily if they allow themselves, cloanto has sewn up the emulation angle and hyperion is giving classic 68k a new breath of life. they could have handled it a little better, multiple licenses and that but still. i almost had pondered throwing 2 cents in that thread but staying well out
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Old 08 March 2019, 21:19   #2069
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does the amiga 600's keyboard have an internal microcontroller (like a500's keyboards) ?
I usually repair a600 keyboards cutting 1mm or more as the guide in prb.hardware says, but this time all the keys are not working and I have artifacts on screen (for example: in the indianapolis 500 "intro", you have a cursor that wait your answer -the game is code protected- ; now when I press a key, three or more cursor appears)
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Old 08 March 2019, 21:22   #2070
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No, in the A600 the keyboard controller is on the motherboard. The keyboard is just the membrane and switches.
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Old 08 March 2019, 23:40   #2071
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thanks.
where is located? could it be broken?
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Old 09 March 2019, 02:13   #2072
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Did you try systest (by keirf)?
Maybe it can help to narrow down the problem.

Other suggestions here.

PS: I wanted to search for it on Aminet, but the main website is unreachable. Is this just temporary or did I miss something?
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Old 09 March 2019, 03:47   #2073
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thank you
I've cut another 1mm and now the keyboard is partially working, I think I'll look for an adapter (ps/2 or usb), possibly cheap
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Old 09 March 2019, 14:35   #2074
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Or you could buy a new membrane.
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Old 09 March 2019, 14:47   #2075
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Or you could buy a new membrane.
Which I did with my A1200. I costs 30€, which isnt cheap, but it worked really fine and I'd buy it again.
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Old 13 March 2019, 21:13   #2076
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If I have asimCDFS, allegroCDFS and CacheCDFS all installed together, how do I know which filesystem has priority?

Also which CD-Rom Filesystem is considered the best overall?
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Old 14 March 2019, 00:37   #2077
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You don't "install" an FS in Amiga. You just add the libraries and (possibly) patches to support it.
So for hard-disks for example, you can have extra file-systems without actually removing any.
On the other hand, if something patches the same library calls (in our case CD I/O), then I guess the last one that installs its patches "wins".
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Old 14 March 2019, 01:26   #2078
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Ok here's one that's bugged me and before I hunt down my Amiga 500 manual, why is Clean Up always ghosted out on the Special menu in Workbench 1.3?

Whatever I do, I can never clean up the icons. This is having booted a 1.3.2 disk, shift click the icons to tidy up or no icons at all, always ghosted!

What gives?
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Old 14 March 2019, 01:48   #2079
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You don't "install" an FS in Amiga. You just add the libraries and (possibly) patches to support it.
So for hard-disks for example, you can have extra file-systems without actually removing any.
On the other hand, if something patches the same library calls (in our case CD I/O), then I guess the last one that installs its patches "wins".
There's nothing patching CD I/O (except possibly IDEfix). Which CD filesystem is used is entirely dependent on your active DOSdriver(s). You may have several active at once.
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Old 14 March 2019, 02:00   #2080
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Filesystems don't have priority as such - for media like CDs, Zip drives, and non-native floppy disks, they are generally loaded on demand by a mountlist. These are text files that reside in the DEVSOSDrivers drawer, and describe the parameters needed for the OS to be able to read a drive, including geometry, how it's connected to the Amiga, and filesystem used. These mountlists are scanned and loaded during the normal boot process. Whichever filesystem is specified by the CD mountlist, that's the one that will be used and all others will simply be ignored.

So have a look in your Devs drawer and see which mountlist file is used for your CD drive - usually it'll be CD0 or similar. Check the tooltypes in the file's icon, and if there's no mention of a filesystem, load the file into any text editor and look for a line specifying the filesystem. That'll tell you which is the filesystem used.
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