Amiga questions you've always been too embarrassed to ask

[blizz1220]

Why does Amiga Amiga 500 has monochrome video via RCA ?

Is it because the signal was already on the motherboard somewhere ?

[T_hairy_bootson]

I would assume the B&W composite was a cost cutting excercise on both the a500 and a2000 since the A1000 had colour.

[Cymru]

Originally Posted by ara

Why was the parallel port of the Amiga 500 and 2000 different from the LPT port (IEEE 1284) in PCs (especially the 5V pin)? Was it used anywhere else or just a random idea of the Amiga/Commodore designers?

As you may recall, the parallel port was re gendered on the Amiga 1000 and had to use a special cable for printers (gendered changed); it was never meant to compete with the PC parallel port as was the serial port. I believe RoyBates is correct as to using it for its full 8-bit data path for more than printing.

[blizz1220]

Originally Posted by T_hairy_bootson

I would assume the B&W composite was a cost cutting excercise on both the a500 and a2000 since the A1000 had colour.

I figured as much I was actually guessing that maybe the b&w signal
exists somewhere near that area so they decided to let it out to play
for reasons known only to them

[lukassid]

Why when os 3.1 is installing on the hard drive, many important files like Installer are not copied to it?

[Toni Wilen]

Originally Posted by blizz1220

I figured as much I was actually guessing that maybe the b&w signal
exists somewhere near that area so they decided to let it out to play
for reasons known only to them

Video hybrid chip (Chip that converts Denise digital RGB to analog RGB) has b&w video out pin.

Creating b&w video out is simple. Color composite requires extra components (coils, crystal, caps, delay line, etc..) and also PAL/NTSC need different components/values.

[blizz1220]

I really didn't expect anyone to know the answer to that
one , thanks Toni
Now where's me screwdriver

EDIT : Yes , now it makes perfect sense , it would be
actually cheap and useful solution if you will use software
that only requires monochrome monitor ...

[Cymru]

I've always felt (and used) the composite (BW) output was designed for diagnostic work as a quick picture on any old monitor.

[hooverphonique]

Originally Posted by xArtx

Q:
Is there such a thing as "bit level access" on an Amiga disk?
or am I making that up?

No.. the smallest size you can read/write at a time is 16 bits, iirc (presuming we're talking floppy)..

[demolition]

Originally Posted by hooverphonique

No.. the smallest size you can read/write at a time is 16 bits, iirc (presuming we're talking floppy)..

I thought you had to write an entire track? So it is possible to sync to the existing track accurately enough?

[hooverphonique]

Originally Posted by demolition

I thought you had to write an entire track? So it is possible to sync to the existing track accurately enough?

hehe.. probably not, but in theory, you can ask the controller to write one word, right!?

[StingRay]

Originally Posted by hooverphonique

No.. the smallest size you can read/write at a time is 16 bits, iirc (presuming we're talking floppy)..

The smallest size you can read is 8 bit, DSKBYTR makes it possible.

[demolition]

Originally Posted by StingRay

The smallest size you can read is 8 bit, DSKBYTR makes it possible.

But I guess you have no way of knowing which part of the track you have read?

[hooverphonique]

Originally Posted by StingRay

The smallest size you can read is 8 bit, DSKBYTR makes it possible.

right.. been many years since I played with this stuff, so I just assumed it would be word-sized like many other data registers usually used to hold data for DMA

[Lonewolf10]

Originally Posted by thomas

BFE101 is the parallel port.

Fire/left button on the first game port is bit 6 of BFE001.
Fire/left button on the second game port is bit 7 of BFE001.

Bit 6 is for left mouse button, so bit 7 is for right mouse button?

Do any amiga's support the middle button, or wheel, or were they added on mice long after Amiga's were created?

Which leads on to my next question (which I don't believe has been asked yet). When referring to more than one mouse (the electrical kind) do you say mouses or mice?

[blizz1220]

Originally Posted by Lonewolf10

Bit 6 is for left mouse button, so bit 7 is for right mouse button?

Do any amiga's support the middle button, or wheel, or were they added on mice long after Amiga's were created?

You can use PC serial port 3btn mouse and WheelMouse.Woks nice but
only in Apps and Workbench.Few games work with it.

Originally Posted by Lonewolf10

Which leads on to my next question (which I don't believe has been asked yet). When referring to more than one mouse (the electrical kind) do you say mouses or mice?

Mices

[demolition]

Originally Posted by Lonewolf10

Bit 6 is for left mouse button, so bit 7 is for right mouse button?

Do any amiga's support the middle button, or wheel, or were they added on mice long after Amiga's were created?

Both bits 6 and 7 are for the left button, just different ports. Right mouse button is not so easy to read since it is connected to the POT inputs. After some configuration, the RMB can be read off address $DFF016.
Since there are two POT pins on each port, it can also support the middle button, however it wasn't standard and you need special software make it work.

I've never seen anyone using PC serial mice on an Amiga, how does that work? On the serial port? Because it definately won't work on the mouse port except using some active adapter, and that would be silly since serial mice are so horrible to begin with. An Amiga deserves a mouse with at least 50 Hz reporting rate.

[blizz1220]

Originally Posted by demolition

I've never seen anyone using PC serial mice on an Amiga, how does that work? On the serial port? Because it definately won't work on the mouse port except using some active adapter, and that would be silly since serial mice are so horrible to begin with. An Amiga deserves a mouse with at least 50 Hz reporting rate.

You need this http://aminet.net/package/driver/input/SerMouse221

And this (attached)

You can use them both at the same time no problem
I never found one that was optical or had a wheel
And if it can't play Cannon Fodder blah

[OddbOd]

Originally Posted by Lonewolf10

Which leads on to my next question (which I don't believe has been asked yet). When referring to more than one mouse (the electrical kind) do you say mouses or mice?

According to the Oxford, American Heritage and Merriam-Webster dictionaries either form is acceptable though mice is by far the more common of the two.

Would you believe that mouse is an acronym for Manually Operated User Selection Encoder? It's a truth fact according to Doug Engelbart-Simpson. This weak attempt at humor brought to you by the colour black, the number i and the fact that I only slept for 2 hours yesterday

[thomas]

Originally Posted by Lonewolf10

Bit 6 is for left mouse button, so bit 7 is for right mouse button?

No, it's like I said: bit 6 is for the (left) button of the first game port (usually referred to as "mouse port") and bit 7 is for the (left) button of the second game port (usually referred to as "joystick port").

Both ports are equal. If you connect a mouse to it, the bit is for the left mouse button. If you connect a joystick to it, the bit is for the (first or only) fire button. They use the same lines on the cable.

The right mouse button is not connected to the CIA.

Originally Posted by demolition

it can also support the middle button, however it wasn't standard and you need special software make it work.

The middle button is supported by the OS in the same standard way as other input. You just need some software which reacts on middle mouse presses.

I think AWeb uses the middle mouse button to open the context menu for links.