From: manjo on

"Jean-Yves Avenard" <me(a)privacy.net> wrote in message
news:462a426a$0$25441$5a62ac22(a)per-qv1-newsreader-01.iinet.net.au...
> cyrille de brebisson wrote:
> > hello,
> >
> > if having 2 50+ talk together is your aim, just take 2 usb cables, cut
them
> > and solder them together... faster, cheaper, and will work better...
> >
>
> you mean USB 4-pins right to make a cross-over serial cable?

Yes... it is important to make that clear :-)

but then, USB cross-over would not work
so it's gotta be 4-pin serial "USB"

manjo
P.S.
i would love to see HP provide a pair of donlges
-one at the mini usb end to convert to 4-thoward HP and
-the other on USB-A end to adapt levels and connections for true RS232 9-pin
DB connector.

That would be like the good old times
-single yet multifunctional cable


From: James M. Prange on
Harold A Climer wrote:
> If the new Samson HP50G serial cable is true RS-232 would I need a
> null modem cable for two HP50's to talk to each other? If this is
> true do they make anything like a gender changer in format that does
> the same thing as a null modem cable?

Presumably you could use a pair of Samson Cables' adapters with a
M-M null modem (or equivalent components) between them.

But for communication between a pair of 50gs, why both converting
from the 3.3V signal to RS-232 and then back to 3.3V again? Surely
the 50g signal should be compatible with another 50g, and, I
expect, various other devices.

Just make yourself a cable with a "USB 4-pin mini-B" connector on
each end, with the ground pins connected straight through, each
calculator's transmit pin connected to the other's receive pin,
and the battery+ pin left unconnected.

The reason for leaving battery+ disconnected is to avoid a current
loop when the battery voltages in the two calculators aren't
exactly the same. I suppose that a possible alternative would be
to connect the battery+ pins, remove the battery from one
calculator, and power both calculators from the other, but that
doesn't appeal to me.

--
Regards,
James

From: dot on
On Sat, 21 Apr 2007 16:11:33 -0400, "James M. Prange"
<jmprange(a)i-is.com> wrote:

>Just make yourself a cable with a "USB 4-pin mini-B" connector on
>each end, with the ground pins connected straight through, each
>calculator's transmit pin connected to the other's receive pin,
>and the battery+ pin left unconnected.

You say that as though it were easy. Good luck trying to just "find"
a USB flat 4-pin connector that is compatible with the hp50g form
factor. Then *if* you do find one, you aren't likely to be able to
make yourself a cable by putting those connectors on each end.

In the Portland, Or. metropolitan area, I have checked several sources
and the closest suitable connector to be found was a USB type A to
flat 4 adaptor in a kit of various adaptors selling for $30 at Fry's.
If you ask for a "USB 4 pin mini-B" connectorized cable, you will soon
discover that the form factor won't be compatible with the hp50g.

I checked electronics stores, camera stores, and the so-called big box
consumer electronics outlets (Best Buy, Circuit City, et al).

I *wish* it were as simple as you make it sound. I have a bag full of
ST3232 chips, all the misc components and Tiwags schematic all set to
go! Now if I could just lay my hands on those compatible connectors!

In the meantime, I bought the Samson Cables version, which doesn't
seem to work at 2400 Baud, yet it does work at 4800 Baud (using Conn4x
with the PC). I really need 1200 Baud but it's not supported and ....
oh well.

-Dot-
From: Jim D. on
Dot,

My tests have indicated at 9600 baud and below conn4x incorrectly times
out on XMODEM transfers. It is probably machine dependent, so you may
see 4800.

I spent a considerable amount of time with a serial analyzer checking
byte by byte that the calculator was attempting to send the correct
data, and it does. Further, the serial analyzer notes any incorrectly
sent characters, and it no time did it see any.

So I will say that the 50G and the cable DO work correctly at 2400
baud.

Jim

dot wrote:
> On Sat, 21 Apr 2007 16:11:33 -0400, "James M. Prange"
> <jmprange(a)i-is.com> wrote:
>
>> Just make yourself a cable with a "USB 4-pin mini-B" connector on
>> each end, with the ground pins connected straight through, each
>> calculator's transmit pin connected to the other's receive pin,
>> and the battery+ pin left unconnected.
>
> You say that as though it were easy. Good luck trying to just "find"
> a USB flat 4-pin connector that is compatible with the hp50g form
> factor. Then *if* you do find one, you aren't likely to be able to
> make yourself a cable by putting those connectors on each end.
>
> In the Portland, Or. metropolitan area, I have checked several sources
> and the closest suitable connector to be found was a USB type A to
> flat 4 adaptor in a kit of various adaptors selling for $30 at Fry's.
> If you ask for a "USB 4 pin mini-B" connectorized cable, you will soon
> discover that the form factor won't be compatible with the hp50g.
>
> I checked electronics stores, camera stores, and the so-called big box
> consumer electronics outlets (Best Buy, Circuit City, et al).
>
> I *wish* it were as simple as you make it sound. I have a bag full of
> ST3232 chips, all the misc components and Tiwags schematic all set to
> go! Now if I could just lay my hands on those compatible connectors!
>
> In the meantime, I bought the Samson Cables version, which doesn't
> seem to work at 2400 Baud, yet it does work at 4800 Baud (using Conn4x
> with the PC). I really need 1200 Baud but it's not supported and ....
> oh well.
>
> -Dot-
From: dot on
So you think it is a Conn4x problem rather than the cable? I suppose
that is possible. Is your serial analyzer a stand alone protocol
analyzer device, or a port monitor PC based program?

-Dot-

On Sat, 21 Apr 2007 19:41:16 -0400, "Jim D." <nospam(a)nospam.com>
wrote:

>Dot,
>
>My tests have indicated at 9600 baud and below conn4x incorrectly times
>out on XMODEM transfers. It is probably machine dependent, so you may
>see 4800.
>
>I spent a considerable amount of time with a serial analyzer checking
>byte by byte that the calculator was attempting to send the correct
>data, and it does. Further, the serial analyzer notes any incorrectly
>sent characters, and it no time did it see any.
>
>So I will say that the 50G and the cable DO work correctly at 2400
>baud.
>
>Jim
>
>dot wrote:
>> On Sat, 21 Apr 2007 16:11:33 -0400, "James M. Prange"
>> <jmprange(a)i-is.com> wrote:
>>
>>> Just make yourself a cable with a "USB 4-pin mini-B" connector on
>>> each end, with the ground pins connected straight through, each
>>> calculator's transmit pin connected to the other's receive pin,
>>> and the battery+ pin left unconnected.
>>
>> You say that as though it were easy. Good luck trying to just "find"
>> a USB flat 4-pin connector that is compatible with the hp50g form
>> factor. Then *if* you do find one, you aren't likely to be able to
>> make yourself a cable by putting those connectors on each end.
>>
>> In the Portland, Or. metropolitan area, I have checked several sources
>> and the closest suitable connector to be found was a USB type A to
>> flat 4 adaptor in a kit of various adaptors selling for $30 at Fry's.
>> If you ask for a "USB 4 pin mini-B" connectorized cable, you will soon
>> discover that the form factor won't be compatible with the hp50g.
>>
>> I checked electronics stores, camera stores, and the so-called big box
>> consumer electronics outlets (Best Buy, Circuit City, et al).
>>
>> I *wish* it were as simple as you make it sound. I have a bag full of
>> ST3232 chips, all the misc components and Tiwags schematic all set to
>> go! Now if I could just lay my hands on those compatible connectors!
>>
>> In the meantime, I bought the Samson Cables version, which doesn't
>> seem to work at 2400 Baud, yet it does work at 4800 Baud (using Conn4x
>> with the PC). I really need 1200 Baud but it's not supported and ....
>> oh well.
>>
>> -Dot-