ps/2 port on a pc

R

Randy Day

Guest
I have an old DOS (yes, DOS) laptop that I want
to use in a project. I want to have two-way
communication, but the ONLY port this thing has
is a ps/2 port.

I can find lots of info on sending chars TO the
PC, but I can't find anything on sending
characters OUT the port to my micro. Is there a
register I can POKE, an interrupt I need to call?

I have QBasic on the laptop, so I can PEEK and
POKE as necessary.

Any advice is greatly appreciated.
 
On Sun, 25 Aug 2013 06:06:29 +1000, Randy Day <randy.day@sasktel.netx>
wrote:

I have an old DOS (yes, DOS) laptop that I want
to use in a project. I want to have two-way
communication, but the ONLY port this thing has
is a ps/2 port.

I can find lots of info on sending chars TO the
PC, but I can't find anything on sending
characters OUT the port to my micro. Is there a
register I can POKE, an interrupt I need to call?

I have QBasic on the laptop, so I can PEEK and
POKE as necessary.

Any advice is greatly appreciated.
Click to expand...

The keyboard has very little output capacity but you can send a code out
to light the number lock, caps lock and scroll lock leds. Look those up
might find some information for you. There was also a hobbyist made usb
password dongle on the web. If you can find it, it has information on what
codes (and a little of how) are sent. The usb thing is just an interface
the registers to poke and peek will be the same. Ideally you should use
the serial port.
 
On 2013-08-24, Randy Day <randy.day@sasktel.netx> wrote:

I have an old DOS (yes, DOS) laptop that I want
to use in a project. I want to have two-way
communication, but the ONLY port this thing has
is a ps/2 port.

I can find lots of info on sending chars TO the
PC, but I can't find anything on sending
characters OUT the port to my micro. Is there a
register I can POKE, an interrupt I need to call?
Click to expand...

the port doesn't communicate in characters it commnicates in bytes,
if you haven't got a copy of RBIL yet, get one.

IIRC this is covered in PORTS.TXT

I have QBasic on the laptop, so I can PEEK and
POKE as necessary.
Click to expand...

There were things you could do on some keyboards that would crash
GW-BASIC, I don't recall if QBASIC was also succeptible,


It it possible you will need to write an ISR, so youd'd need something
stronger. I know "Turbo C 2.0" is a free download from Embacadero after
registration. or DJGPP if you have a 386

--
⚂⚃ 100% natural

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---
 
In article <op.w2b896bkwei6gd@phenom-pc>, eather@tpg.com.au says...

[snip]

> The keyboard has very little output capacity but you can send a code out

I've seen any number of sites that say you CAN
send characters, and that describe the protocol
for communicating, but none of them talk about
the how-to's from the pc side.

to light the number lock, caps lock and scroll lock leds. Look those up
might find some information for you. There was also a hobbyist made usb
password dongle on the web. If you can find it, it has information on what
codes (and a little of how) are sent. The usb thing is just an interface
the registers to poke and peek will be the same. Ideally you should use
the serial port.
Click to expand...

Believe it or not, this laptop only has one
i/o port: the ps/2 port. No serial, no lpt.

I will do some searching on the blinking
lights thing, though. Thanks.
 
In article <kvbad0$e16$1@gonzo.reversiblemaps.ath.cx>, jasen@xnet.co.nz
says...

[snip]

the port doesn't communicate in characters it commnicates in bytes,
if you haven't got a copy of RBIL yet, get one.
Click to expand...

<googles RBIL>

> IIRC this is covered in PORTS.TXT

Oo! Interesting! There is indeed a
section on the 804x keyboard controller.

I'd be ecstatic if all I had to do was
check a status bit, drop a byte into
60h, and have the controller handle the
actual signalling. Can it really be that
simple? Time to fire up the 'scope!

There were things you could do on some keyboards that would crash
GW-BASIC, I don't recall if QBASIC was also succeptible,
Click to expand...

If it is, I'm sure I'll find out! ;)
 
On 2013-08-25, Randy Day <randy.day@sasktel.netx> wrote:

IIRC this is covered in PORTS.TXT

Oo! Interesting! There is indeed a
section on the 804x keyboard controller.

I'd be ecstatic if all I had to do was
check a status bit, drop a byte into
60h, and have the controller handle the
actual signalling. Can it really be that
simple? Time to fire up the 'scope!
Click to expand...

That's sounds about right, it's been 20 years.

--
⚂⚃ 100% natural

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---
 
On Sat, 24 Aug 2013, Randy Day wrote:

I have an old DOS (yes, DOS) laptop that I want
to use in a project. I want to have two-way
communication, but the ONLY port this thing has
is a ps/2 port.
Click to expand...
What kind of laptop has no serial port or parallel port, or PCMCIA slot
for such an interface?

For that matter, what kind of laptop doesn't have any of that, but has a
PS/2 port? The PS/2 port is used for a keyboard, and I can't think of any
laptop from back then that had the port for an external keyboard, that
sort of thing came only when USB started becomiing the norm. Or PS/2 is
used for connecting a mouse, but a DOS laptop isn't likely to have much
use for a mouse to have the port, and before mice were standard, often
other interfaces were used (like serial port, and a card the expansion
bus).

It seems most likely you think you have a ps/2 port but likely it's
something else.

If the laptop has a parallel port, back then the parallel port was
generally one way, except it had a bunch of status lines to read from the
printer, so one could do an odd two-way communcation through a parallel
port, there was a whole "standard" for this. If it's serial, then you
just communicate over it, everything's in place.

Michael
 
On Sunday, August 25, 2013 10:06:05 AM UTC-7, Michael Black wrote:
On Sat, 24 Aug 2013, Randy Day wrote:


I have an old DOS (yes, DOS) laptop... but the ONLY port this thing has
is a ps/2 port.

What kind of laptop has no serial port or parallel port, or PCMCIA slot
for such an interface?
Click to expand...

Probably a contracted model that just acts a a terminal to a
bar-code scanner. That kind of setup was pretty common for a
few years, for inventory and warehouse folk to hang on their necks.
 
In article <alpine.LNX.2.02.1308251300530.28924@darkstar.example.org>,
et472@ncf.ca says...
On Sat, 24 Aug 2013, Randy Day wrote:

I have an old DOS (yes, DOS) laptop that I want
to use in a project. I want to have two-way
communication, but the ONLY port this thing has
is a ps/2 port.

What kind of laptop has no serial port or parallel port, or PCMCIA slot
for such an interface?
Click to expand...

It does have 2 pcmcia slots, but I'm not
going to spend money on cards or time on
finding drivers. The port only has to
transmit a few command bytes to the micro
once in a while, so emulating a kbd is more
than adequate.

For that matter, what kind of laptop doesn't have any of that, but has a
PS/2 port? The PS/2 port is used for a keyboard, and I can't think of any
laptop from back then that had the port for an external keyboard, that
Click to expand...

The brand may give you a clue to its age: "Digital".

The port does work with an external keyboard, and
there's a mouse symbol as well as a kbd symbol next
to it, so I assume it can do double duty.

sort of thing came only when USB started becomiing the norm. Or PS/2
is
used for connecting a mouse, but a DOS laptop isn't likely to have much
use for a mouse to have the port, and before mice were standard, often
other interfaces were used (like serial port, and a card the expansion
bus).

It seems most likely you think you have a ps/2 port but likely it's
something else.
Click to expand...

No, it works with a keyboard. The machine does have
an integrated trackball, but I've never tried to
test that.

Now, *maybe* the unit ran an early version of
Windows, but it's got DOS loaded, and even
navigating menus in QBasic shows some lag, so I
don't think it was a speed demon even in its day.

However, the display (320x240!) is flawless, and
the unit does a mean spreadsheet, so I'd like to
repurpose it; it'd make a good console for a
logic analyzer or other uC project.
 
On 2013-08-26, whit3rd <whit3rd@gmail.com> wrote:
On Sunday, August 25, 2013 10:06:05 AM UTC-7, Michael Black wrote:
On Sat, 24 Aug 2013, Randy Day wrote:


I have an old DOS (yes, DOS) laptop... but the ONLY port this thing has
is a ps/2 port.

What kind of laptop has no serial port or parallel port, or PCMCIA slot
for such an interface?

Probably a contracted model that just acts a a terminal to a
bar-code scanner. That kind of setup was pretty common for a
few years, for inventory and warehouse folk to hang on their necks.
Click to expand...

barcode scanner could be RS-232 or PS/2,

--
⚂⚃ 100% natural

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---
 
On 2013-08-26, Randy Day <randy.day@sasktel.netx> wrote:

The port does work with an external keyboard, and
there's a mouse symbol as well as a kbd symbol next
to it, so I assume it can do double duty.
Click to expand...

With the right a splitter cable you you should be able to attach both
simultaneously.

No, it works with a keyboard. The machine does have
an integrated trackball, but I've never tried to
test that.

Now, *maybe* the unit ran an early version of
Windows, but it's got DOS loaded, and even
navigating menus in QBasic shows some lag, so I
don't think it was a speed demon even in its day.
Click to expand...

What CPU? if it's got ps/2 mouse I'd expect at-least 80286

--
⚂⚃ 100% natural

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---
 
"Randy Day" <randy.day@sasktel.netx> schreef in bericht
news:MPG.2c8310695ef84e019896cd@aioe.org...
In article <kvbad0$e16$1@gonzo.reversiblemaps.ath.cx>, jasen@xnet.co.nz
says...

[snip]

the port doesn't communicate in characters it commnicates in bytes,
if you haven't got a copy of RBIL yet, get one.

googles RBIL

IIRC this is covered in PORTS.TXT

Oo! Interesting! There is indeed a
section on the 804x keyboard controller.

I'd be ecstatic if all I had to do was
check a status bit, drop a byte into
60h, and have the controller handle the
actual signalling. Can it really be that
simple? Time to fire up the 'scope!

There were things you could do on some keyboards that would crash
GW-BASIC, I don't recall if QBASIC was also succeptible,

If it is, I'm sure I'll find out! ;)
Click to expand...

Found RBIL no problem but not PORTS.TXT.
Suppose this document covers the problem as well,
http://www.computer-engineering.org/ps2keyboard/
though I like to find PORTS.TXT as well.

petrus bitbyter
 
In article <521bdae0$0$610$e4fe514c@dreader34.news.xs4all.nl>,
petrus.bitbyter@hotmail.com says...

[snip]

Found RBIL no problem but not PORTS.TXT.
Suppose this document covers the problem as well,
http://www.computer-engineering.org/ps2keyboard/
though I like to find PORTS.TXT as well.
Click to expand...

The doc I used was PORTS.A in Inter61D.zip.
 
In article <kvetko$dam$1@gonzo.reversiblemaps.ath.cx>, jasen@xnet.co.nz
says...

[snip]

> What CPU? if it's got ps/2 mouse I'd expect at-least 80286

According to the interwebs, it has a 486DX2/50.

Maybe the fact that it has a 'government salvage'
sticker on the back means it picked up a few bad
habits working for the government! <g>
 
"Randy Day" <randy.day@sasktel.netx> schreef in bericht
news:MPG.2c85a6eab12eabf9896cf@aioe.org...
In article <521bdae0$0$610$e4fe514c@dreader34.news.xs4all.nl>,
petrus.bitbyter@hotmail.com says...

[snip]

Found RBIL no problem but not PORTS.TXT.
Suppose this document covers the problem as well,
http://www.computer-engineering.org/ps2keyboard/
though I like to find PORTS.TXT as well.

The doc I used was PORTS.A in Inter61D.zip.
Click to expand...

Found thanks.

petrus bitbyter
 
In article <alpine.LNX.2.02.1308251300530.28924@darkstar.example.org>,
et472@ncf.ca says...
On Sat, 24 Aug 2013, Randy Day wrote:

I have an old DOS (yes, DOS) laptop that I want
to use in a project. I want to have two-way
communication, but the ONLY port this thing has
is a ps/2 port.

What kind of laptop has no serial port or parallel port, or PCMCIA slot
for such an interface?

For that matter, what kind of laptop doesn't have any of that, but has a
PS/2 port? The PS/2 port is used for a keyboard, and I can't think of any
laptop from back then that had the port for an external keyboard, that
sort of thing came only when USB started becomiing the norm. Or PS/2 is
used for connecting a mouse, but a DOS laptop isn't likely to have much
use for a mouse to have the port, and before mice were standard, often
other interfaces were used (like serial port, and a card the expansion
bus).

It seems most likely you think you have a ps/2 port but likely it's
something else.

If the laptop has a parallel port, back then the parallel port was
generally one way, except it had a bunch of status lines to read from the
printer, so one could do an odd two-way communcation through a parallel
port, there was a whole "standard" for this. If it's serial, then you
just communicate over it, everything's in place.

Michael
Click to expand...

I've got a magnetic card reader/writer. I have an old Inspiron 4100 that
I have to use with it since it has both the PS2 plug and a real serial
port.

All the PS2 connector does is supply the 5V current for the thing. The
serial port is where the action happens.
 
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