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Great Hierophant
February 9th, 2009, 09:22 AM
There are two things I would like to do but don't have all the hardware to do them. Therefore, I would like to simulate the experience.

1. IBM 5150 Cassette port

I don't have a TRS-80 Color Computer-style cassette cable or a data recorder. Electronic Arts' Music Construction Set allows the sound to be output to a cassette recorder for four channel sound. I would love to hear samples of it.

2. 64K EGA 640x350
To obtain 16 colors in the 640x350 mode, your EGA card requires 128K of RAM. While I have an IBM EGA card (which only has 64K of RAM without an expansion board), I don't have a 350-line color monitor (which are expensive.) I would love to see pixel-perfect uncompressed screenshots of how the EGA card would interpolate the 16-color data into 4-color output.

Trixter
February 9th, 2009, 09:57 AM
I don't have a TRS-80 Color Computer-style cassette cable or a data recorder. Electronic Arts' Music Construction Set allows the sound to be output to a cassette recorder for four channel sound. I would love to hear samples of it.


You and me both. I hear the cables are fairly easy to make, so this should be easy for you.

When I start up the Soundcard museum in 2010 I will definitely be recording samples from both, since I want to see if the generation method is different.



I would love to see pixel-perfect uncompressed screenshots of how the EGA card would interpolate the 16-color data into 4-color output.

Huh?

Or did you mean you just want to see what true EGA looked like?

Great Hierophant
February 9th, 2009, 11:46 AM
You and me both. I hear the cables are fairly easy to make, so this should be easy for you.

When I start up the Soundcard museum in 2010 I will definitely be recording samples from both, since I want to see if the generation method is different.



Huh?

Or did you mean you just want to see what true EGA looked like?

I would like to see what color EGA looks like on a 350-line monitor, but I suspect it would not be substantially different than what it would look like on a VGA monitor. (I can determine what monochrome EGA looks like on a monochrome monitor.)

If the EGA only has 64K of RAM, it cannot display 640x350x16. I believe I read somewhere that it reduces the color depth to 640x350x4. I want to see an example of how it reduces the color depth from 4-bit to 2-bit.

Fallo
February 9th, 2009, 12:19 PM
I would like to see what color EGA looks like on a 350-line monitor, but I suspect it would not be substantially different than what it would look like on a VGA monitor. (I can determine what monochrome EGA looks like on a monochrome monitor.)

In 350-line modes, EGA uses 8x14 text. If you want to see this font, all you have to do is switch into 640x350 mode on any VGA card.


If the EGA only has 64K of RAM, it cannot display 640x350x16. I believe I read somewhere that it reduces the color depth to 640x350x4. I want to see an example of how it reduces the color depth from 4-bit to 2-bit.

IBM's original EGA card needed a daughterboard to have the full 128k, but essentially all clones had 128k onboard. With 64k, you do only get 4 colors (the default being cyan-magenta-white on black). Windows used to support this, as well as the 640x350 monochrome mode.

VGA does support the mono mode. It can be activated in BASIC with SCREEN 10, although it will refuse to switch into it unless you are in Mode 7 (mono text mode).

Now, regarding Music Construction Set and the cassette cable, this was a feature that was lifted directly from the original Apple II version of MCS. The TRS-80 cassette cables can be found on Ebay occasionally:

http://cgi.ebay.com/TRS-80-printer-and-cassette-interface_W0QQitemZ260359081035QQcmdZViewItemQQptZ LH_DefaultDomain_0?hash=item260359081035&_trksid=p3286.c0.m14&_trkparms=72%3A1205%7C66%3A2%7C65%3A12%7C39%3A1%7C 240%3A1318%7C301%3A1%7C293%3A1%7C294%3A50

...although I wouldn't recommend this one unless you have a use for that printer.

However, connecting the cassette port to a stereo may not be a good idea. I've heard that playing beeping sounds through stereo speakers is bad for them.

gerrydoire
February 9th, 2009, 02:05 PM
I'm looking for an EGA Wonder that will work in a IBM Portable.

There is a special EGA Wonder that has the connector.

:cool:

Great Hierophant
February 9th, 2009, 02:25 PM
In 350-line modes, EGA uses 8x14 text. If you want to see this font, all you have to do is switch into 640x350 mode on any VGA card.

IBM's original EGA card needed a daughterboard to have the full 128k, but essentially all clones had 128k onboard. With 64k, you do only get 4 colors (the default being cyan-magenta-white on black). Windows used to support this, as well as the 640x350 monochrome mode.

VGA does support the mono mode. It can be activated in BASIC with SCREEN 10, although it will refuse to switch into it unless you are in Mode 7 (mono text mode).

Now, regarding Music Construction Set and the cassette cable, this was a feature that was lifted directly from the original Apple II version of MCS. The TRS-80 cassette cables can be found on Ebay occasionally:

http://cgi.ebay.com/TRS-80-printer-and-cassette-interface_W0QQitemZ260359081035QQcmdZViewItemQQptZ LH_DefaultDomain_0?hash=item260359081035&_trksid=p3286.c0.m14&_trkparms=72%3A1205%7C66%3A2%7C65%3A12%7C39%3A1%7C 240%3A1318%7C301%3A1%7C293%3A1%7C294%3A50

...although I wouldn't recommend this one unless you have a use for that printer.

However, connecting the cassette port to a stereo may not be a good idea. I've heard that playing beeping sounds through stereo speakers is bad for them.

I assume that the EGA looks at the first two bits to determine the color if only 64K is available to it. I really would prefer to see all 350-line modes on an IBM 5154 Enhanced Color Display.

I saw that auction, but I am concerned that the cassette interface may not be a DIN.

Fallo
February 9th, 2009, 02:46 PM
I saw that auction, but I am concerned that the cassette interface may not be a DIN.

It's worse than that. I located a higher-resolution picture of the TRS-80 Pocket Printer, and it turns out the cassette cable is attached to the printer and not a separate piece.