Hello readers,
I cleaned the first of my RM03 drives today. The drive is quite clean
even after several years of no attention. Just a few spiders webs and
tiny dead spiders, and little dust. I picked up this drive in Turin
Italy, together with Edward several years ago. I cannot remember doing
it, but the head lock pin was in the lock position.
After cleaning and a good inspection (I found a small metal bracket
piece next to the PSU output plugs, and have not found where it came
from!), I mounted a mains power plug to the drive cable. Massbus cable
is attached to the drive, the other end is not connected to anything.
After setting all circuit breakers ON (two inside the drive, two at the
rear side next to the running hours counter), I plugged the mains in
and switched mains on. I hear humming of the fans, so it seems OK.
However, this is my problem: the door latch stays locked, I cannot open
the lid. I want to open the lid to clean the inside of the drive bay.
After some reading (EK-RM023-TD-001_RM02_03_Tech_May78.pdf), I found
this in chapter 4.4 (page 4-7):
The initialize sequence starts with the receipt of a Massbus INIT
signal from either port A or B. This sequence is used to condition both
the adapter and drive circuits to a known reset state. The functional
block diagram for the initialize command is shown in Figure 4-5.
The Massbus INIT signal (whether coming from port A or B) clears the
AT A bit in the attention summary register in the IF module. In the CS
module, it is converted to the MBA clear signal which performs the
following:
1. Clears the enable search latch
2. Sets the on latch
3. etc.
So, do I understand this correctly that without an initial Massbus INIT
signal the lid remains locked? Or has this RM03 drive a "lock issue"?
If somebody has an RM03 drive, is it possible to open the lid without
Massbus cables hooked to the RH70 or RH11 controller? Is that Massbus
connection required + INIT command to unlock the lid?
I have not yet cleaned the other two RM03 drives, and I do not want to
apply power without cleaning and inspection! So, I cannot check whether
all 3 drives keep the lid locked.
I forgot to take the camera with me, but I will take pictures!
Thanks,
- Henk
I am doing a bit of VAXELN programming and I am trying to get the Datagram
Service to only read packets of a certain EtherType, but unless I use
promiscuous mode, nothing is read. Here is the relevant code:
form.format = ELN$K_NI_PTT;
form.mux.ptt = 0x0360;
mode = 0;
pad = 0;
eln$ni_connect(&status, &portalId,
config.clist.list[i].control_port, &dispatchPort, &form, NULL, &mode, NULL,
NULL, NULL, NULL, NULL, &pad);
Anyone know why this might not return any packets at all when I wait on the
port?
Regards
Rob
2016-01-23 13:54 GMT+01:00 Noel Chiappa <jnc at mercury.lcs.mit.edu>:
> > From: Mattis Lind
>
> > I don't have an capacitance / ESR meter so I cannot check it.
>
> If you do a lot of work with analog components (and it sounds like you do),
> it's probably worth getting capacitance and ESR meters, they can be
> obtained
> (new) on eBay for not that much. I have one of each that I got that way;
> their quality is pretty good, considering how little I paid for them (I
> didn't think I'd be using them enough to make it worth paying out a lot for
> really good ones). I haven't used the ESR meter much, but the capacitance
> meter works quite well, and has been very helpful. Of course, it can't be
> used in-circuit, but...
>
>
Yes. agree with you.I really should get one. I have been thinking I need to
get one every time I get my head into anther PSU and then everything is
sorted out and the PSU seems to work fine and I forget about it. I have
been looking at the DerEE DE-5000 which looks nice and has got good reviews
as far as I can tell. What meter do you have and recommend?
> Alas, I can't (easily) help with the VT100 question! :-)
>
That's a pity!
>
> Noel
>
/Mattis
Hi,
I've built a Harddisk-Controller-Emulator for my system which accesses
a IDE (PATA) harddisk with an ATMega in PIO mode. It works like a charm
except for one WD harddisk. The harddisk itself works fine with MS-DOS
6.22 and FreeBSD but refuses to work with my ATMega.
On reading or writing a sector, right after the command is issued, the
error bit is set in the status register, and the error register indicates
an ABRT.
# ABRT:
# indicates the requested command has been aborted due to a
# drive status error (such as not ready or write fault) or because
# the command is invalid.
Right after power up and after the disk got ready, I issue the IDENTIFY
command and read the data back which works perfectly. After that I
read sector 0 and this fails.
I use LBA since the harddisk states that is supportes LBA. Nevertheless
I also tried accessing the harddisk with CHS mode and got the same error.
I tested other harddisks which support either CHS+LBA or CHS only. All
of them work perfectly.
What happens after powerup to read block 0 of the disk in LBA mode:
- Setup AVR ports and so on
- wait until RDY gets high
- wait until BSY gets low
- issue a Drive/Head register Command with value 0
- wait until BSY gets low
- issue a Command Register Command with value 0xEC (identify device)
- *read data*
- process and print out data
- wait until BSY gets low
- issue a Sector Count register Command with value 0
- issue a Sector Number register Command with value 0
- issue a Cylinder Low register Command with value 0
- issue a Cylinder High register Command with value 0
- issue a Drive/Head register Command with 0 + 0xE0 (LBA, Drive 0)
- issue a Command Register Command with value 0x20 (Read Sector)
- *read data*
*read data*:
- wait until BSY gets low
- check ERR bit in the Status register <- set on cmd 0x20 here
- wait until DRQ gets high
- issue a Data register Command with no data
- put /RD on low
- read 512 bytes of data
- put /RD on high
- check ERR bit in the Status register
Issuing a Command works always like setting /CS0, /CS1, /DA0, /DA1,
/DA2 to low, and then set the needed signals to high so the desired
command is indicated.
When data has to be transfered with this command, the lower 8 bits
are put then onto the port, /WR is set to low afterwards, 3 nop()
are done and /WR is set back to high.
Does anyone see an error what could make the drive behave like I said?
- ATA IDENTIFY works, and the drives data can be read
- after a read or write sector command is issued, the status register
directly goes 0xd0 (busy) and with the 2nd fetch 0x59 (not busy, drq
set, err set)
Regards, Oliver
Short: R27 in my VT100 PSU is hot and smelling. Why?
Long: I think it has been 20 years since I powered up this VT100 so I did
it carefully. Used a Variac and a bench supply. It switched just fine and
delivered the steady 5V out when the input was at approx 50V (115V input).
All the other voltages looked fine at full AC input. But there was this
little smell from R27.
Then I plugged everything in and fired it up. Now there were considerable
more heat generated in R27 which is a 13W / 1kOhm power resistor. But I
still had 4.99V over a random TTL gate on the logic board so the PSU seemed
to operate just fine.
R27 is part of the snubber network on the primary side of this forward-type
SMPS PSU. But why it it getting so hot. Is it normal? I have completely
forgotten how a VT100 smell when running...
Anyone out there with a VT100 that can put his or her nose above R27 and
tell me the temperature?
One interesting thing is that DEC apparently did some kind of ECO since my
resistor is 1k while the schematic tell me 500 ohm. It doesn't seems to
have been replaced.
I checked D27 and that one looked fine. Could there be some marginal
problem in the circuit somewhere that cause excessive hearing of R27? The
primary side looks fairly simple so there are not many components that
could fail completely which wouldn't cause complete death of the PSU.
C19 is part of the snubber network and is a 0.0033uF 1600VDC film
capacitor. Can these go marginal somehow? I never heard of that but maybe?
/Mattis
On 01/23/2016 07:48 PM, Mike Boyle wrote:
>
>
> On Sat, Jan 23, 2016 at 7:28 PM, Eric Christopherson
> <echristopherson at gmail.com <mailto:echristopherson at gmail.com>> wrote:
>
> On Sat, Jan 23, 2016, Jim Brain wrote:
> > On 1/23/2016 2:18 PM, drlegendre . wrote:
> > >First off, my bad - I thought the OP was wanting to change the
> device ID
> > >(which is not the drive number, btw**) on a genuine 1541. I'd
> have no idea
> > >how it's done with one of the SD-based drive emulators.
> > Google is still a friend:
> >
> >
> https://www.google.com/search?q=sd2iec+change+device+numbers&ie=utf-8&oe=ut…
> >
> > There are no external switches on some of these drives.
> >
> > But, the BASIC commands used to switch device numbers on the
> 1541 also work
> > on these units, and putting an extra char at the end of the
> command will
> > make the changes permanent, as I recall.
> >
> > Jim
>
> Jim, don't you sell a device that's useful for temporarily
> switching off
> specific drives so the device numbers can be changed more easily?
>
> --
> Eric Christopherson
>
>
>
>
> --
So I guess the question now is should I change the sd drive or the
original floppy? Thank you all for all the wonderful help god bless you all!
> *
> Mike's ?
> Honda ATC 3wheeler
> ? Shop?
> for LIFE!!!*
> *
> Have a blessed day!*
I just resurrected a nice HP 2631G dot matrix line printer:
Like here: http://www.hpmuseum.net/display_item.php?hw=316
It has 3 empty slots for extra character ROMs, so I am itching to install some... Anyone has ever made a dump of these character ROMs? Apparently these are the same as the extra character sets ROMs used in the 264x terminal. Math, Line Draw and Japanese would be particularly fun... And French too as a nod to my roots.
Marc
