Peculiar boot up on V20 with Super XT BIOS.

[fjk61011]

I have a an 5150 with a Super XT BIOS. and V20 chip.

Using a Hercules VGA card PC boots and loads DOS from an XT-IDE card.

How ever with an MDA card it boots to screen with A>> C>> F6 F11.

Nothing happens when I press any key.

Keyboard works in other set up.

EDIT: Tis an XT class machine.

 

[fjk61011]

The A>> C>> F6 F11 I think is the XT-IDE screen.

 

[Plasma]

If you are referring to this bios, you need to uncomment IBM_PC = 1 for the 5150.

You also need to set the configuration switches on the motherboard for the type of video card installed.

 

[fjk61011]

Tis in fact an XT class machine, 8 slots.

I've set the switches for an MDA card.

 

[fjk61011]

I'm not sure if it's a clone or an ibm machine

 

[fjk61011]

minuszerodegrees.net

The switch block is similar to column 2, row 2. It is very hard to tell when switch is on or off.

Using a Genoa Systems CGA card and an IBM Colour Graphics Monitor system works.

 

[fjk61011]

I'm thinking now that the monitor I was using, the brightness/contrast needs to be adjusted.

 

[fjk61011]

Yes, 'tis the brightness/contrast.

 

[modem7]

I have a an 5150 with a Super XT BIOS. and V20 chip.

Tis in fact an XT class machine, 8 slots.

I'm not sure if it's a clone or an ibm machine

So, for now, we'll consider it an XT clone.

with a Super XT BIOS

Is this the 'Super XT BIOS' shown at [here] ?

( Screenshots at bottom of page. )

Nothing happens when I press any key.

Keyboard works in other set up.

Is that "other set up" also an XT-class computer?

 

[modem7]

Is this the 'Super XT BIOS' shown at [here] ?
( Screenshots at bottom of page. )

I note that if a working (and compatible) keyboard is disconnected from the XT-class motherboard, the POST of this BIOS will not indicate a keyboard error (either by way of a 301 error code, or something like "keyboard error").

 

[fjk61011]

So, for now, we'll consider it an XT clone.


Is this the 'Super XT BIOS' shown at [here] ?

( Screenshots at bottom of page. )


Is that "other set up" also an XT-class computer?

Malwarebytes won't let me open the Super XT BIOS link.

The XT works now with Brightness and Contrast adjusted.

 

[fjk61011]

I'm back at Vintage Computing after a break from my 10,000 brick Lego Titanic.

 

[modem7]

The XT works now with Brightness and Contrast adjusted.

And the keyboard is working ?

 

[modem7]

... after a break from my 10,000 brick Lego Titanic.

Very appropriate for your location.

 

[fjk61011]

And the keyboard is working ?

Yes. It was probably working but Brightness and Contrast hid the C: prompt.

 

[fjk61011]

Very appropriate for your location.

I was at the bottom of the drydock in Belfast where she was fitted out.

 

[vwestlife]

The XT-IDE displays its key functions in high intensity, while the rest of the BIOS and DOS messages are in low intensity. If you have your monitor's contrast turned down too far, low-intensity text will disappear while high-intensity text will remain visible. That explains the mystery.