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giobbi
January 21st, 2014, 07:57 AM
Hello,

I got a strange boot behavior on my 5160.

Usually it boots from its internal 20 Mb Hard disk (IBM Ms-Dos 3.30). Today it booted twice with IBM Basic (1.0 I think). I'm not sure but I believe it didn't read the HD (I simply saw the hd led blink quickly once). I didn't ever know there was a ROM with Basic for booting purposes...

At the third reboot, it started as usual with Ms-Dos.

Is there any key sequence (maybe I had a stuck key and I didn't know) or any other reason for that?

--Giovi

Stone
January 21st, 2014, 08:39 AM
Any time there is no boot device available, for whatever the reason, the 5150/5160 will perform a boot to BASIC which is stored in a ROM chip (provided this ROM chip is installed on the motherboard).

SpidersWeb
January 21st, 2014, 09:57 AM
Since you said the HDD flickered, that means the HDD controller ROM initialized and the drive detected (otherwise you'd get a big delay and a 1701 error).
It's possible it's having trouble reading the first track. I can't confirm what the issue is, but personally my first steps would be:

- reseat HDD controller
- clean/reseat 20 pin data cable to drive
- use SpeedStor to perform a non-destructive low level format (I think it's called 'Re-initialise' ?)

But yes, if it can't boot, it goes to MS BASIC - not terribly useful without the cassette port.

Stone
January 21st, 2014, 10:14 AM
- use SpeedStor to perform a non-destructive low level format (I think it's called 'Re-initialise' ?)I don't think SpeedStor does a non-destructive LLF but if you've done it wih SpeedStor I will definately have a look at it the next time I get to my SpeedStor machine. As far as I remember, re-initialize is just a regular LLF, IOW, a complete wipe.

SpinRite, OTOH, does a non-destructive LLF as that is its primary purpose.

Either way, the OP should look into a LLF as it's quite possible the drive is getting ready to croak the format. And, along these lines, it's also possible that Track 0 is about worn out and the drive is about to become toast.

SomeGuy
January 21st, 2014, 10:27 AM
Yea, 5160 (XT), 5170 (AT), and apparently even some early PS/2s had Basic in ROM. Not really very useful without the cassette port since they can't save to disk.

Chuck(G)
January 21st, 2014, 11:32 AM
Well, if you're running early PC-DOS (not MS-DOS), the BASICA command relies on the presence of the BASIC-in-ROM. Microsoft added GWBASIC to the non-IBM variety.

vwestlife
January 21st, 2014, 11:44 AM
Old stepper-motor hard drives are thermally sensitive. In some cases the drive will refuse to boot or will give read errors when it is cold, but then it will work fine once it warms up. Or on the other hand, if the drive was formatted when it was cold, then it might work fine when you first turn it on but then give errors when it is warmed up.

It is best to wait until the drive is fully warmed up (at least a half-hour after turning it on) before formatting it or writing data to it, to avoid these kinds of problems.

giobbi
January 21st, 2014, 12:59 PM
thank you all, asap I will open and take a look at the internal connectors and cards, I put my hands inside a couple of days ago, and mine aren't fairy hands ;-) so it's possible I moved something ...

--Giovi

vwestlife
January 21st, 2014, 01:29 PM
Yea, 5160 (XT), 5170 (AT), and apparently even some early PS/2s had Basic in ROM. Not really very useful without the cassette port since they can't save to disk.

All PS/2s have ROM BASIC as far as I know, as well as most PS/1s and even some Aptivas.

fs5500
January 21st, 2014, 08:15 PM
IBM BASIC in ROM version is version C1.10 on PC 5160.
C1.00 was used on PC 5150 early version.

RWallmow
January 22nd, 2014, 05:31 AM
All PS/2s have ROM BASIC as far as I know, as well as most PS/1s and even some Aptivas.

I had no idea they carried that on until the Aptiva days, that's crazy, what purpose would ROM basic have served them in the day and age of Windows 95, lol

How is ROM basic accessed on a PS/2, I have an 8086 model 25 and it doesn't boot to basic with no bootable disks, just a large ascii graphic of a disk and insert disk message.

vwestlife
January 22nd, 2014, 06:34 AM
I had no idea they carried that on until the Aptiva days, that's crazy, what purpose would ROM basic have served them in the day and age of Windows 95, lol

Any IBM that came with IBM DOS versions up to 5.00 would need to have ROM BASIC in order to run the BASICA (or in the case of 5.00, QBASIC) that came with IBM DOS. Later revisions of IBM DOS 5.0 removed the ROM BASIC requirement because IBM wanted to sell it to PC-clone users as well.


How is ROM basic accessed on a PS/2, I have an 8086 model 25 and it doesn't boot to basic with no bootable disks, just a large ascii graphic of a disk and insert disk message.

If you write a small assembly language program to trigger an INT 18h, it will either dump you into ROM BASIC or give you the computer's boot failure message.