Amiga questions you've always been too embarrassed to ask

[Sasuke]

What is the bit value of each single block represented by XCOPY?

[Jope]

That would be a very long post if answered literally. There are quite a few different ways you can put bits together to make one Amiga track.

If I interpret your question as how much data fits on an Amiga track: In cooked form (only sector contents, aka DosCopy) it is 5632 bytes per track which comes from 512 bytes per sector times eleven.

In raw form, MFM encoded (aka Nibble copy), including all the sector headers it is 11968 bytes per track.

[van_dammesque]

Why does the turbo floppy function in WinUAE crash games? Timing with the chipset?

[ShK]

The dragon mouse pointer easter egg for AmigaOS 3.9 made by Angela "Nessie" Schmidt for her birthday that happens on March 30th and was introduced in Boing Bag 2 in March 2002. Is it possible to make it visible elsewhere than in Early Startup, e.g., in Workbench with a key combination?

[NLS]

Doubt it.
But in reality, I posted because I just realized we have the same birthday with her.

[Jope]

Originally Posted by van_dammesque

Why does the turbo floppy function in WinUAE crash games? Timing with the chipset?

Timing with the loader code running on the CPU will be totally wonky.

Originally Posted by ShK

The dragon mouse pointer easter egg for AmigaOS 3.9 made by Angela "Nessie" Schmidt for her birthday that happens on March 30th and was introduced in Boing Bag 2 in March 2002. Is it possible to make it visible elsewhere than in Early Startup, e.g., in Workbench with a key combination?

This is a part of the "strap" ROM module, so it doesn't show up elsewhere.

[Calabazam]

At last, how do you convert Miami CPS to KB/s?

[lyzanxia]

Why is there such a large help/del key on the a500 keyboard.
Did anyone ever use the help key? (I did not )

[Jope]

Originally Posted by Calabazam

At last, how do you convert Miami CPS to KB/s?

There are 1024 characters in one kB.

Originally Posted by lyzanxia

Why is there such a large help/del key on the a500 keyboard.

Anyone's guess. Aesthetics?

Did anyone ever use the help key? (I did not )

I have used it many times in the old days as well. Games probably don't use it for much of anything. These days also OS3.2 makes better use of the Help key, giving you the OS user guide.

[Calabazam]

Originally Posted by Jope

There are 1024 characters in one kB.

So, 1 character means 1 bit?

[Daedalus]

Maybe they keyboard spacing was intended to match PC keyboards, which were beginning to standardise with the block of 6 keys above the arrow keys at the time, but with just two functions needed (Delete and Help), so each key is 1.5x the standard key width.

The Help key has a function to trigger opening documentation or similar when it is held and an Intuition object used (e.g. clicking on a gadget or selecting a menu item), and that came in with OS 3.0 IIRC. It's up to the application to implement this however, and not many did. But for me at least Help is also a very commonly used key as part of the Exchange hotkey (Ctrl + Alt + Help).

And a few games did use it, for example Birds of Prey uses Delete / Help as the rudder controls.

[ShK]

Originally Posted by Calabazam

So, 1 character means 1 bit?

KB/s = CPS / 1024

[thomas]

Originally Posted by Calabazam

So, 1 character means 1 bit?

Please define what cps and kb/s mean in your opiniton.

I think we agree that cps means "characters per second". While kb may mean either "kilobyte" or "kilobit".

A character is a byte. So 1024 characters is equal to one kilobyte. A byte is 8 bits so you need 128 characters to get one kilobit.

Jope above correctly wrote kB with a lower case k and an upper case B. This makes its meaning unique as kiloByte. With a lower case b it would be kilobit.

I am not sure, but I think the lower case k may mean 1000 while the upper case K is 1024. But that's probably up to the person you ask.

[Calabazam]

Originally Posted by thomas

Please define what cps and kb/s mean in your opiniton.

I think we agree that cps means "characters per second". While kb may mean either "kilobyte" or "kilobit".

A character is a byte. So 1024 characters is equal to one kilobyte. A byte is 8 bits so you need 128 characters to get one kilobit.

Jope above correctly wrote kB with a lower case k and an upper case B. This makes its meaning unique as kiloByte. With a lower case b it would be kilobit.

I am not sure, but I think the lower case k may mean 1000 while the upper case K is 1024. But that's probably up to the person you ask.

Yeah i agree about kB and kb. In french there is no confusion because there are kilobits for kb and kilooctets for kB, which makes it clear about the 8 ratio.

Character was unclear because in a web browser or email software it could be related to actual letters or numbers on screen instead of bits. Seems like an old fashioned way of giving download speed. And cps would more naturally to me (in professional context) relate to count per second of radioactivity.

[NLS]

Well, to contribute to the mess.
Kilo universally means 1000 of a lower unit.
In IT we always meant 1024 because everything is usually base 2 or base 16.
Except for... hard disk marketing people (and then almost all other storage).
So IEC came up with changing the traditional IT measures to "kibi" (mebi, gibi, tebi) instead of "kilo" to make kilo back to 1000 for the IT illiterate masses.
So the "old" kb now is called "kib".
I ignore this change in my life. I am still in JEDEC standards.

Back to topic.

CPS = Characters Per Second.
Back in ASCII days (and terminals, BBS etc.), this is 1:1 Bytes Per Second as every character is mapped 0-255 in the ASCII table or a variation of it.

Capitalization of Bytes vs Bits, is not a standard. Many people write kb or Kb or KB for kilobytes. Usually bits are written fully.
So in the era of FttH and 5G we say "Gbit or gigabit" written fully.

The big question is why we measure bits some times and other times, bytes.
This is because data are rarely multiples of bytes nowadays. Even single characters are now usually 2 bytes each (Unicode). Also there are arbitrary bits used for headers, checksums and other type of "overhead" in the information transferred.
So it is better for transfers to talk in bits instead of bytes.

For the original question: 1 CPS = 1 byte per second = 8 bits per second.
BUT with "character" (in CPS) we imply that any overhead is out of the equation, so the terminal manages to get one character displayed per second, but in reality transfer is a bit faster to manage that. Because for example in the default 8N1 mode, you need 10 bits to transfer 8 bits of actual data.
(1 start bit + 8 bits data + no parity bit + 1 stop bit)

[Daedalus]

It might not be universal, but the lower-case b is almost always used to mean bit, in contrast to the capital B for byte. The K however is a different story. In SI unit terms, using k for kilo- should always be lower-case. However, because of the confusion between decimal and binary multipliers, a new set of units was defined for binary-based multipliers. This uses the symbol KiB, with a capital K and a capital B, to represent 1,024 bytes.

[Sasuke]

How many watts does an A500 consume?

[Daedalus]

According to this, around 10W. The PSU (in)efficiency will mean a bit more will be turned to heat in the PSU too, the exact amount will depend on the individual PSU but probably in the 2-5W range.

[cloverskull]

Is an A4000 fully hardware capable of booting into NTSC or PAL mode just with the change of the jumper? I was reading other Amigas have hardware specific PAL or NTSC features.

[Jope]

Originally Posted by cloverskull

Is an A4000 fully hardware capable of booting into NTSC or PAL mode just with the change of the jumper? I was reading other Amigas have hardware specific PAL or NTSC features.

It is. The 28M oscillator should also be changed to match the jumper setting, if you want to fully convert the machine. No harm will come to the computer if you can't be bothered to change it though.