3 Jan
2014
3 Jan
'14
9:50 a.m.
I have come across a strange problem with my MicroVAX 2000. If the hard disk
is not plugged in I get absolutely nothing on the console, as if the machine
was dead.
I have perused the technical documentation and I cannot find anything that
describes this behaviour. Does anyone know why it might do this and which
signal(s) prevent the console coming up?
I need this to be able to do some initial testing of a basic emulation of
the RD5x disks with an FPGA.
Thanks
Rob
3 Jan
3 Jan
9:57 a.m.
On 3 January 2014 14:50, Robert Jarratt <robert.jarratt at ntlworld.com> wrote:
I have come across a strange problem with my MicroVAX
2000. If the hard disk
is not plugged in I get absolutely nothing on the console, as if the machine
was dead.
Could be that the power supply needs a load present...
3:56 p.m.
-----Original Message-----
From: cctalk-bounces at classiccmp.org [mailto:cctalk-
bounces at classiccmp.org] On Behalf Of David Brownlee
Sent: 03 January 2014 14:57
To: General Discussion: On-Topic and Off-Topic Posts
Cc: DEC discussion list.
Subject: Re: No Console on MicroVAX 2000 if Disk Not Plugged In
On 3 January 2014 14:50, Robert Jarratt <robert.jarratt at ntlworld.com>
wrote:
I thought that the system board and the fans would present enough load for the PSU, but it
seems not, I needed the disk to be powered for enough current to be drawn to make the PSU
work.
Regards
Rob
I have come across a strange problem with my
MicroVAX 2000. If the
hard disk is not plugged in I get absolutely nothing on the console,
as if the machine was dead.
Could be that the power supply needs a load present... 
4:11 p.m.
On Fri, Jan 3, 2014 at 12:56 PM, Robert Jarratt
<robert.jarratt at ntlworld.com> wrote:
I thought that the system board and the fans would present enough load for the PSU, but
it seems not, I needed the disk to be powered for enough current to be drawn to make the
PSU work.
Regards
Rob
http://www.bitsavers.org/pdf/dec/vax/410/EK-VTTAA-TM-001_VS2000_TechRef_Jul…
Chapter 6
Resistor Load Module
The system box must use a resistor load module when less than two
drives are installed. The resistor load module regulates the power
supply in the expansion boxes when only one drive is installed in each
box. The power supply needs a minimum amount of current drawn for it
to regulated properly...
7:31 p.m.
-----Original Message-----
From: cctalk-bounces at classiccmp.org [mailto:cctalk-
bounces at classiccmp.org] On Behalf Of Glen Slick
Sent: 03 January 2014 21:12
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: No Console on MicroVAX 2000 if Disk Not Plugged In
On Fri, Jan 3, 2014 at 12:56 PM, Robert Jarratt
<robert.jarratt at
ntlworld.com>
wrote:
Thanks, I hadn't read the whole manual and missed that bit.
Regards
Rob
I thought that the system board and the fans would present enough load
for the
PSU, but it seems not, I needed the disk to be powered for enough
current to be drawn to make the PSU work.
Regards
Rob
http://www.bitsavers.org/pdf/dec/vax/410/EK-VTTAA-TM-
001_VS2000_TechRef_Jul87.pdf
Chapter 6
Resistor Load Module
The system box must use a resistor load module when less than two drives
are installed. The resistor load module regulates the power supply in the
expansion boxes when only one drive is installed in each box. The power
supply needs a minimum amount of current drawn for it to regulated
properly...
10:15 a.m.
New subject: [DECtec] No Console on MicroVAX 2000 if Disk Not Plugged In
Never mind, I have discovered that it seems to be the absence of sufficient
power being drawn.
Regards
Rob
-----Original Message-----
From: DECtec [mailto:dectec-bounces at dectec.info] On Behalf Of Robert
Jarratt
Sent: 03 January 2014 14:51
To: General Discussion: On-Topic and Off-Topic Posts; DEC discussion list.
Subject: [DECtec] No Console on MicroVAX 2000 if Disk Not Plugged In
I have come across a strange problem with my MicroVAX 2000. If the hard
disk is not plugged in I get absolutely nothing on the console, as if the
machine was dead.
I have perused the technical documentation and I cannot find anything that
describes this behaviour. Does anyone know why it might do this and which
signal(s) prevent the console coming up?
I need this to be able to do some initial testing of a basic emulation of
the
RD5x disks with an FPGA.
Thanks
Rob
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DECtec mailing list
http://dectec.info
To unsubscribe from this list see page at:
http://dectec.info/mailman/listinfo/dectec_dectec.info
10:23 a.m.
On 01/03/2014 09:50 AM, Robert Jarratt wrote:
I have come across a strange problem with my MicroVAX
2000. If the hard disk
is not plugged in I get absolutely nothing on the console, as if the machine
was dead.
I have perused the technical documentation and I cannot find anything that
describes this behaviour. Does anyone know why it might do this and which
signal(s) prevent the console coming up?
I need this to be able to do some initial testing of a basic emulation of
the RD5x disks with an FPGA.
The power supply needs more of a load to run than a bare machine
assuming its not totally dead.
There was a load board that could be in there for no disk ops to keep
the PS happy.
Allison
I'm back!
12:04 p.m.
On 01/03/2014 10:51 AM, emanuel stiebler wrote:
On 2014-01-03 08:23, allison wrote:
Brief off topic this once... Please.
I dropped the list back in july last year due to its high noise content
especially the other.
I heard people were wondering and making assumptions. I'm healthy and
very busy.
Allison
Allison
I'm back!
Yes, good to "read" you. We were wondering already ;-)
3858
days inactive
3859
days old
8 comments
5 participants
participants (5)
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abs＠absd.org -
ajp166＠verizon.net -
emu＠e-bbes.com -
glen.slick＠gmail.com -
robert.jarratt＠ntlworld.com