Troubles when dialing in pulse mode.

On Tuesday, June 1, 1999 at 10:19:41, Roman Milukov pressed the buttons for Oleg
Pritula about the “New text editor for Spectrumists”:

OP>> 2All: None of the real people had problems with
OP>> connecting and working
OP>> Acorp' 33.6? The tables are as follows: when dialing a number in
OP>> pulse mode, at
OP>> at an arbitrary moment of dialing the next digit, the
OP>> DCD indicator lights up and
RM> the modem
OP>> hangs up. And so on all the time. It was not possible to
OP>> completely
OP>> dial the number.

RM> IMHO due to interference with the power supply to myself. Maybe it (+5V) is connected to your momed
RM> with a thin long wire? And the capacity is about +5, +12 normal. At -5, -12 they are a bit thin, of course, but not particularly so. Perhaps
because of this?

RM> Do you have momed?

What kind of container is it? The one that is installed in parallel on the phone. line in the socket
telephone? So I installed it and removed it. The result is similar. :-/

RM> Right now I have Acorp 33.6 (rocwell), it works quite well
RM>.

Hmm... Here EM voiced the idea that it might be incompatible with my
PBX. How realistic is this? I kind of doubt it. IMHO, the reason is entirely different. What?!

\\|// ╟─┤asta la vista !!! Curator from the prefecture:
o(@ @)o -=POWer/WDG/AF=-
-----ooO-(_)-Ooo----- √E-Mail: w...@hello.to

OP> At +5, +12 normal. Here at -5, -12 they are a little thin, of course, but not particularly.

(In my Acorp, +12V and -12V are not used.)

OP> Perhaps because of this?

No, there is not much current there.

RM>> Is there a momed?

OP> What kind of capacity? The one that is installed in parallel on the phone. line in the socket

No!
It is advisable to place power supply containers directly on the ISA connector (or very close, I don’t know how it’s structurally
done there). Schaub don't worry. For +5V
-uF 100-470; and at -5V - this is generally a special case - there in the modem itself it goes to the op-amp, and there is not a single blocking connector! I put 4.7 uF directly into the modem. But it wouldn’t be necessary. It’s better to put it on the slot, 10-30 uF.

I’m not saying that this will definitely help you, but you need to do it so as not to
think about dietary interference.

09 Jun 99 12:12, Roman Milukov wrote to Oleg Pritula:

RM> It is advisable to install power supply containers right on the ISA connector (or very close, I don’t know how constructively you
RM> did it there). Schaub don't
RM> worry. At +5V - µF 100-470; and at -5V - this is generally a special
RM> case - there in the modem itself it goes to the op-amp, and not a single
RM> blocking connector! I put 4.7 uF right in the modem. But it’s not necessary
RM>. It’s better to put it on a slot, 10-30 uF.

Yes, the modem already has a lot of capacitors. And in the PC there are no capacitors
located next to the slots.

RM> I’m not saying that this will definitely help you, but it needs to be done so that
RM> you don’t have to worry about power supply interference.

(001-$XEMA:

___ ___
ZX-BUS |T | |T |
A8,A9,A10 >------| o----| o------> ISA-SLOT
|___| |___|

Exactly 1 piece 1533TL2.

Cures glitches in the form of chatter on the address bus.

Looks like FK threw a fake on this matter...

Kirill Frolov. [ZX]

KF> (001-$XEMA:

[skip circuit]

KF> Cures glitches in the form of chatter on the address bus.

I confirm! 100%

KF> Looks like FK threw a fake on this case...

No, this cartoon hasn’t been there yet. :) Although, there were some prerequisites: as the cause of the glucodrome, a version was accepted
about a mismatch between the ISA and Z80 timings (misphasing of system signals), which
later (after heated debates in HARDWARE.ZX)
was rejected. The reason was precisely the 'blinking' of the address lines. TL2
copes with it at 5+.

There is a desire to write the third (last) FAQ on connecting Hayes according to Misha
Kondratiev’s scheme. The scheme has already been tested (in essence, it has practically not changed.
Several
“little things” have appeared that make life easier. + Mandatory (!) recommendations
on the design.), has shown its “indifference” to
different modems: the super-glitchy
(precisely on the bus!)
MX-2496 ('Calpak corparation') and more or less normal
LTI-9624HV-B (v42bis, mnp).

IMHO, this will allow real-life developers to more fearlessly screw
Haes to themselves and use the coolest Wild Mailer. :)

2MK: And your Zmodem is still buggy. ;)

Best regards, Felix.

[IZX]

[Wednesday June 9, 1999] at [12:12:21] Roman Milukov wrote a letter to Oleg
Pritula.
They discussed the topic “Troubles when dialing in pulse mode.”.
Let’s continue what we started...

15 Jun 99 01:59, Felix Knajzev pressed buttons for Roman Milukov:

FK> There is a desire to write the third (last) FAQ on connecting Hayes according to
FK> Misha Kondratiev’s scheme. The circuit has already been tested (in essence, it
FK> has practically not changed. Several 'little things' have appeared that
FK> make life easier. + Mandatory (!) recommendations for constructive
FK> implementation.), has shown its "indifference" to different modems: the super-glitchy (precisely on the bus!) MX-2496 also works reliably
FK> ('Calpak
FK> corparation') and a more or less normal LTI-9624HV-B (v42bis, mnp).

So give the diagram in the echo or to me by netmail.

Sincerely, Yura DOORSFAN
[ZX] [DOORS] [BLACK SABBATH]

FK> I confirm! 100%

Guys, you first make a diagnosis, and then treat!

By the way, when making a subject, sometimes resistors of 100-300 Ohms in series in
each wire of the line help.

FK> There is a desire to write the third (last) FAQ on connecting Haes according to the
FK> Misha
FK> Kondratiev scheme. The scheme has already been tested (in essence, it has practically not
FK> changed.

Write.
But don’t worry about only the 2400/none modem! There are faster ones in nature.

I’m telling you especially for you: in the Acorp 33.6 int there is no -5V capacity at all!
And in the PC, usually the power buses in the mother are routed correctly, and the source is not weak.

KF> (001-$XEMA:
[...]

\\|// ╟─┤asta la vista !!! Curator from the prefecture:
o(@ @)o -=POWer/WDG/AF=-
-----ooO-(_)-Ooo----- √E-Mail: w...@hello.to

RM> Are you saying that his subject is precisely from this?

The subject is from the reel.

Kirill Frolov. [ZX]

^^^^^^^^^^^^^^^^^^^^
FK>> connecting Hayes according to
FK>> Misha Kondratiev’s scheme. The scheme has already been tested (in essence

YY> So give the scheme in the echo or to me by netmail.

When I write it, then I’ll give it to everyone to be torn to pieces. ;)

FK>> I confirm! 100%

RM> Guys, first establish a diagnosis, and then treat!

The diagnosis has already been established. You didn't read my letter carefully and skipped the 'diagnosis'. Yes, this has nothing to do with the subject!
And the Schmitt trigger is the panacea for such a 'diagnosis'
(presence of 'bounce' at the fronts of the address lines [A8, A9, A10]).

RM> By the way, with the subject sometimes resistors of 100-300 Ohm
RM> in series in
RM> each wire of the line help with the subject.

Yes, help. Only their denomination depends on the specific
case: the physical length of the address lines, + the initial
load of these same lines. It is advisable to select them to achieve the 'golden' mean. And the input gestiresis threshold
for 555TL2 is +/-400mV. Such a ferocious thing can make the most notorious feces on a tire look like a god...

I was talking about the telephone line wires! (with the subject! ;)

FK> Yes, they help. Only their nominal value depends on the specific
FK> case: the physical length of the address lines, + the initial
FK> load of these same lines. It is advisable to select them to
FK> achieve the 'golden' mean. And the input threshold of hysteresis
FK> for 555TL2 is +/-400mV. Such a ferocious thing can make
FK> the most notorious feces on the bus look like a god...

And resistors in the address lines... this is already a perversion!
Schmidt triggers are better. :)
By the way, for them it is not the “input hysteresis threshold” that is normalized, it seems, but the switching levels to “0” and “1” - 0.8V and 1.6V, respectively. Yes, indeed, this
solves the problem of “bouncing on signal fronts”, or rather not bouncing, but
indefinite levels (from bouncing - RS-tigger). And imho there shouldn't be any chatter there. Or did you see it on some cool oscilloscope?

FK> “If the MX-2496 works, then EVERYTHING else will work!” (c)
FK> is mine again. :)

That's good. Let's see. :)

RM> I was talking about the telephone line wires! (with the subject! ;)

And 1 kilo-ohm resistors helped me with bouncing on A8, A9, A10
in series with the momed, but TS is better!

RM> And resistors in the address lines... this is already a perversion!

What can you do when you press "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~",
and to you from the modem "~~~I~~~~~~~I~~~~~~~I~~~~~~~~~~~~~~~~~~~~I~~~" ???

RM> Schmidt triggers are better. :)

Yes, it all happened purely by chance. At first there was a latch on TM9,
and then KP11, and then I didn’t get my hands on anything other than TL2, so I sold them
as repeaters :-)

RM> rather than bounce, but indefinite levels (from bounce -
RM> RS-tigger). And imho there shouldn't be any rattling there. Or did you see it on some
RM> cool oscilloscope?

And this is just an assumption and IMHO the only plausible one.

Kirill Frolov. [ZX]

RM> By the way, for them it is not the “input hysteresis threshold” that is normalized,
RM> it seems, but the levels

And the ShmiTT trigger ;) - what do you think this is? ;) What's remarkable
about his work? ;)

RM> switching to “0” and “1” - 0.8V and 1.6V, respectively.
^^^^^^^^^^^
For 555TL2 - 0.9-1.7V

By the way, ;) if it says “input hysteresis threshold” (or “zone
hysteresis”), then it indicates
exactly the input characteristic that I cited above. Because it is precisely this that most
accurately displays the property.

RM> Yes, indeed, this
RM> solves the problem of “bouncing on signal fronts”, or rather
RM> not bouncing, but
RM> of undefined levels (from bouncing - RS-tigger). A

Precisely “bounce”. Or too flat fronts.

RM> chatter imho there should not be
RM> there. Or did you see it on some cool oscilloscope?

It will be. Under certain conditions. Including structural
character (inductive component of connecting conductors, used
element base).

FK> It will be. Under certain conditions. Including those of a constructive
FK> nature (the inductive component of the connecting conductors,
the element base used
FK>).

In general, we’re done. It's already off-topic. If you want to argue about this, go ahead.

FK>> resistance...

RM> But not here! This is bullshit, don't argue with it. Especially in this place.

Look at any writing board - there are a lot of shortcuts and coils in every
second wire.

RM> Damn it! So “bouncing” or “too flat fronts?!!
RM> IMHO these are different things.

IMHO bouncing. After all, 1k resistors helped (and not bad).

Kirill Frolov. [ZX]

Without “IMHO” - different. And why be so nervous? :)
I just gave one more example ("flatness" of fronts) when
the Schmitt trigger makes life more fun. And that’s all.

For “our” case (only an inadequate response of *certain*
modems to addresses A8, A9, A10 for the MK circuit) there is exactly
“bouncing on the fronts”, and it is the Schmitt trigger that cures it. Unless,
of course, this “bounce” does not go beyond the capabilities of the
TS itself.

Take a more truthful reference book (I highly recommend “The Art
of Circuit Design” in three volumes) and define the concepts of “bounce
at the fronts” and “flatness of the fronts.” And everything will become clear and understandable.

KF> IMHO it's a rattle. After all, 1k resistors helped (and not badly).

A certain damped oscillatory process occurs at the fronts (remember
“the capacitor is charged in a sinusoid”? ;). It depends on many factors. When the level "1" is low, it can be perceived by the CMOS input as a bounce, although it is not one. You can also treat with a resistor...

FK> Without “IMHO” - different. And why be so nervous? :)
FK> I just gave one more example ("flat" fronts) when
FK> the Schmitt trigger makes life more fun. That's all.

Why have fun? You can make the fronts steeper with a simple repeater.
You just need to come up with a circuit solution that would work with most
modems. And another for the rest, the smaller part. And to say in the affirmative that
this is for such people, and this is for such people...
Or maybe one thing for everyone.
But, necessarily, not complicated.

FK> For “our” case (only the inadequate response of *certain*
FK> modems to addresses A8, A9, A10 for the MK circuit) it is precisely
FK> “bouncing on the fronts” that occurs, and it is the trigger Schmitta treats him. If,

Listen, by the time the IOW/IOR signals appear, the address signals should already
be clearly established. And stand like that, even for some time after the end of IOR/IOW.
With level “1” of at least 3.3V (for CMOS). We don't have a problem there with level "0". And
what is being done there on their fronts is not important.
But if the input modem is TTL, then it will be necessary to ensure clarity of “0” with a level
of no more than 0.8V. That's it.

FK> Take a more truthful reference book (I highly recommend 'The Art
FK> of Circuit Design' in three volumes) and define the concepts of "bounce
FK> onfronts" and "flat fronts". And everything will become clear and understandable.

I was "defined" by more than three volumes. And not only about "circuitry".

RM> Some damped oscillatory process
RM> occurs at the fronts (remember “the capacitor is charged in a sinusoid”? ;). It depends
RM> on many factors. When the level "1" is low, it may be perceived
RM> by the CMOS input as bouncing, although it is not. You can also treat
RM> with a resistor...

Amplifying the signal or pulling it up to +5v or GND did not give any results.

Kirill Frolov. [ZX]

FK>> If,

RM> Listen, by the time the IOW/IOR signals appear, the address
RM> signals should already
RM> be clearly established. And stand like that, even for some time
RM> after the end of IOR/IOW.
RM> With level “1” of at least 3.3V (for CMOS). We don't have a problem with level "0" there
RM>. And
RM> what is being done there on their fronts is not important.
RM> But if the input modem is TTL, then you will need to provide
RM> clarity “0” with a level
RM> of no more than 0.8V. That's it.

This is all theory. Those. how everything should actually work.
And that’s how it should work, I don’t argue. But *really* - everything is much more prosaic. For example, do you know how the input logic
for the address lines A0, A1, A2 (ISA) is implemented in the hefty PLCC cockroach of the "MX-2496" modem? I don't. And if these are clock inputs of triggers?
And in this notorious MX-e, this is probably the case.

Lab work:

1. Build a 1-2 Hz multivibrator on any TTL chip with a buffer element at the output (from the same package). TL2 -
do not use! Bye. ;)

2. Apply this signal to the clock input (any one, at least +1, at least -1)
1533(555,155)IE7. IE7 is critical.

3. Check the *correctness* of the invoice.

And how? ;) I have IE7 (series 1533, 155, 555) without TL2 at the input, working on glucodrome. IE5 -works flawlessly.

KF> Boosting the signal or raising it to +5v or GND did not give any results.

I don’t know. I haven't seen it.

...
FK> This is all theory. Those. how everything should really work.
FK> And that’s how it should work, I don’t argue. But *really* - everything goes where

If “it should” but “doesn’t work” you need to look for the reason.
By the way, this is even partly useful. ;) Sometimes you sweat, you look for the reason, and at the same time you remove some other problems. Which may later, in the future, turn out to be "fraught with side effects" for you. And it’s not good to shove summaries and concise notes anywhere.

FK> more prosaic. For example, do you know how the input logic
FK> is implemented for the address lines A0, A1, A2 (ISA) in the hefty PLCC cockroach
FK> of the "MX-2496" modem? I don't. And if these are clock inputs of triggers?
FK> And in this notorious MX-e, this is probably the case.

:) So what? What difference does it make what is done there at the addresses in the absence of IOR/IOW?!!
And when does the percentage set addresses for other devices at all?..
I repeat: at the moment the IOR/IOW appears, the address should already be there, with levels
"0"-<0.8V and "1"->3.3V. And stand like that for some time after the IOR/IOW
disappears (I don’t know how long, but this may be important, because imho writing to the modem occurs
on the falling edge of the IOW).

FK> Laboratory work:

FK> 1. Assemble a 1-2 Hz multivibrator on any TTL chip with a buffer
FK> element onoutput
...
FK> 2. Apply this signal to the clock input (any, at least +1, at least -1)
FK> 1533(555,155)IE7. IE7 is critical.

FK> 3. Check the *correctness* of the account.

FK> And how? ;) I have IE7 (series 1533, 155, 555) without TL2 at the input, working on
FK> glucodrome. IE5 - works flawlessly.

Ha! And it depends on what kind of multivibrator! :) Although I agree, in the simplest case at
1-2 Hz there will be garbage at the moments of switching. Moreover, if you install a buffer, then most likely the Schmitt trigger will not help you later! ;)

...
FK> Well, what is this “fingering” for? :( I just *advised*
FK> literature that seemed to me the most wise. There are others, I
know...

So what, you thought I’d immediately rush to look for your “The Art of Circuit Design” and
"determined"?!

RM> Here. Just like an amplifier. That is, it doesn’t just _transmit_, but
RM> with amplification!

Ku~10-20. At this moment (very short) all the feces from the entrance climbs
unhindered to the exit.

RM> And the zone is not small. When the input voltage changes within the
RM> range of 1.25-1-4V, the output
RM> changes within the range of ~0.2-3.3V.

For different TTL series there are completely different thresholds.

RM> Will the front really not become steeper
RM>?!! :-/

No. If at the front there is approximately the same feces that you have given below, then this same feces will be adjusted
for the better depending on which element of the series we pass it through. But *in any case* - it will be worse
than if TL2 (of any series) was used.

There is indicative information on this issue in 'Radio' #1, 1991, p.50:

"... The dependences of the output voltage on the input voltage for inverting elements
of the indicated series are presented in Fig. 1.
(FK: the results of this figure will be given below.)
Because for The threshold switching voltage is assumed to be equal to the
output voltage, it is not difficult to find from these dependencies. It is obvious that the MC series
KR1533 have the highest
threshold switching voltage and, as a consequence, the highest
noise immunity..."

Threshold switching voltage for various TTL series
(withUout=Uin):
(data from the graphs of a certain figure 1. In this journal, the “curves” for the K555 and K155/K531 series are mixed up on the graph! Below
the correct data is given!)

K555 -------- 1.12V
K155/K531 --- 1.4V
KR1533 ------ 1.52V

This is about the question of “how an *ordinary* valve can influence
the curved signal arriving at its input.”

RM> So screw you.

I was already screwed when I checked this *in practice*. :)

RM> Well, if you have something like this going on there:

RM> 5V-----------------------
RM> |
RM> |
RM> | /\/\...
RM> | /\/
RM> | /\/
RM> |_/
RM> 0V----------------------- t

RM> Then you risk getting several instead of one front.

Yes. So it will be.

RM> But for address signals this is not important (to some
RM> extent).

Agree on what? ;)

Once, Fri Jul 23 1999 16:26, Felix Knajzev wrote to Roman Milukov about [Front
and levels. (Troubles when dialing in pulse mode.)]:

FK> There is indicative information on this issue in 'Radio' #1, 1991,
FK> page 50:

[skipped]

FK> (data from the graphs of a certain figure 1. In this magazine, on the graph
FK> the “curves” for the K555 and K155/K531 series are mixed up! Below is the correct
FK> data!)

FK> K555 -=--=--- 1.12V
FK> K155/K531 -=- 1.4V
FK> KR1533 -=--=- 1.52V

connect the 1533rd inverter/LA3 input to output and make sure that there 1.3 V. I measured it myself. maybe a different plant? ;)

All the best.
Dmitry.

... LD..X-TRADE... [ZX]

23 Jul 1999 you wrote here:

FK> Brake. :) Resistors are your idea, i.e. you offered them as
FK> *alternative*.

?!!
2EM: We’ll soon start buying old messages, some people have sclerosis.

I suggested putting resistors in *telephone* wires! In relation to that
first subject that is in parentheses!
And you already said: “yes, yes, this is exactly how you can treat rattling - pushing resistors into the
address lines” (KF also supported you in this). And he started talking about Schmitt triggers.
I then had to edit the subject.
As in the joke: “A fish is covered with scales... But if it were covered with wool, then
there would be fleas there! And a FLE...” :)))

[...]

RM>> 5V-----------------------
RM>> |
RM>> |_ ___ U2
RM>> |_ /\/\/\... ___ U1

DL> I measured it myself. maybe a different plant? ;)

If they’re from Baku, they’ll come with a cup, then anything can come out. Once upon a time we got burned by something like this. In 1992 they assembled Leningrad1.
Synchro was supplied directly from the output of LP5, with transistor assemblies I think
there was tension. So all 555LP5 pulled the synchro input of the VTC 202, but these didn’t do any of them. :-) The batch was about 500 pieces. Although there may have been substandard conditions.
I once spoke with an acquaintance from the plant, so according to him
after the start of perestroika, substandard equipment that was at least in some
functional condition was sold wholesale to radio markets at a favorable price.

With respect, Alex from FFC COMPUTERS.

>E-MAIL: asde...@softhome.net ICQ: #13064553