Re: [M100] m100 maximum baud rate without flow control

[John R. Hogerhuis]

It's largely a problem of the m100... it has a small receive buffer, 64
bytes, and highly software driven display.

But it also depends on the peer and the degree to which it is expeditiously
monitoring and possibly "looking ahead" in incoming data for xoff to flow
off its sending process when the model t request it.

So a single answer is not possible since it is potentially different for
every peer system.

Add in issues with the m100 doing anything else... like displaying text on
the screen and it can be quite slow.

Linux in particular is a poor peer in this regard. To get reasonable speeds
xon xoff isn't really appropriate and you should really roll your own
hardware flow control. With hardware flow control you can use even 38400 or
76800 speeds without data loss.

Windows seems to allow higher than usual baud rates with software flow
control. Probably still 9600 or lower I would think.

-- John.

[M100] m100 maximum baud rate without flow control

[runrin]

hey all,

i was wondering if anyone has done any work determining the maximum baud
rate the m100 supports without xon/xoff flow control? i assumed it was
9600 because thats what most of my machines from that era support
(usually with a 8250 uart).

i've been working on a homebrew computer for some time now, and even
with a dead stable serial clock at 9600 hz i'm dropping characters on
the m100. i thought it was a software issue, but it works perfectly with
my heathkit terminal, so i'm thinking its an m100 problem.

300 baud worked fine, but even as slow as 2600 seemed to be an issue.

thanks!

Re: [M100] Model T clock doubler

[Stephen Adolph]

Yes one new part to add. I will update.
Steve

On Wednesday, November 29, 2023, Ken St. Cyr  wrote:

> Thanks - I'm going to order a set of prototypes boards as soon as you're
> ready to share. Will anything in the parts list change?
>
>
> //Ken S.
> --
> *From:* M100  on behalf of Stephen
> Adolph 
> *Sent:* Wednesday, November 29, 2023 1:13 PM
> *To:* m...@bitchin100.com 
> *Subject:* Re: [M100] Model T clock doubler
>
> Had to do a minor responsibility!  Will post in a week.
>
> On Wednesday, November 29, 2023, Ken St. Cyr  wrote:
>
> Hey Steve -
>
> I went to grab the gerbers from the upgrade page in the wiki, and the
> links aren't working. Would you mind sharing the file for the M100 board?
>
> Thanks!
> //Ken S.
> --
> *From:* M100  on behalf of Stephen
> Adolph 
> *Sent:* Saturday, November 18, 2023 10:54 AM
> *To:* m...@bitchin100.com 
> *Subject:* [M100] Model T clock doubler
>
> Hi everyone,
>
> I've been working towards finishing off my project for increasing the
> speed of the Model T laptops.  The idea is to create a (relatively) easy to
> make and install solution that allows the user to switch the clock rate
> from 2.5 MHz to 5 MHz.
> This is really nice on the 40x8 LCD machines.
>
> The universal software command to switch clock rate is
> OUT 85,1 for 2x mode and
> OUT 85,0 for 1x mode.
>
> Of course the Model T is not designed for this, but in my experience so
> far, it seems reliable.  I really like the upgrade and plan to install in
> all my laptops. Being able to operate in nominal clock mode is of course
> very useful because you may find some software to be incompatible.
>
> Models I have upgraded to date:
> * M100 (NA, early variant, not UK)
> * T102
> * T200
> * NEC PC-8201/8201a
> * Olivetti M10
>
> I am publishing all the information needed to DIY this upgrade. I don't
> have any plans to make these upgrades.  Consider this upgrade only if you
> are comfortable with soldering surface mount parts, and with making minor
> modifications to your laptop.
>
> Upgrades that are done and in the process of documentation are M100, T200,
> NEC.  Upgrades that need a new PCB design still are T102 and M10.  All
> information will be at this site:
>
> https://bitchin100.com/wiki/index.php?title=5MHZ_upgrade_for_Model_T
>
> I am publishing
> * PCB designs for the clock doubler board (there are a few variants)
> * schematic
> * bill of materials for parts you need
> * documentation for building the clock doubler
> * installation documentation per laptop
>
> Things I have discovered while developing this;
> 1.  Power consumption goes up by about 20% when you run at 2x clock.
> 2.  Depending on the speed of your SRAM,  you may need to implement a
> modification to speed that up.  Each model has a specific mod you need.
> 3.  In M100 with the custom socket pinout, in most cases you need to
> upgrade your Main ROM to something faster.  This usually involves an
> adapter board and an EPROM.
> 4.  In the Tandy 200, one must slow down the machine temporarily to access
> the RTC.  There is a specific change for that.
>
> Anyhow, as I complete a particular laptop, I'll post the needed files.
>
> Hopefully this will be of some interest for those inclined to play around
> with hardware.  I have no problem if anyone wants to take the design and
> improve it or change it.
>
> Feel free to contact me directly with questions.
>
> cheers
> Steve
>
>
>
>
>

Re: [M100] Model T clock doubler

[Ken St. Cyr]

Thanks - I'm going to order a set of prototypes boards as soon as you're ready 
to share. Will anything in the parts list change?

[cid:32f88c46-e6bc-44d1-a531-143b90c69e50]

//Ken S.

From: M100  on behalf of Stephen Adolph 

Sent: Wednesday, November 29, 2023 1:13 PM
To: m...@bitchin100.com 
Subject: Re: [M100] Model T clock doubler

Had to do a minor responsibility!  Will post in a week.

On Wednesday, November 29, 2023, Ken St. Cyr 
mailto:k...@stcyrfamily.net>> wrote:
Hey Steve -

I went to grab the gerbers from the upgrade page in the wiki, and the links 
aren't working. Would you mind sharing the file for the M100 board?

Thanks!
//Ken S.

From: M100 
mailto:m100-boun...@lists.bitchin100.com>> 
on behalf of Stephen Adolph mailto:twospru...@gmail.com>>
Sent: Saturday, November 18, 2023 10:54 AM
To: m...@bitchin100.com 
mailto:m...@bitchin100.com>>
Subject: [M100] Model T clock doubler

Hi everyone,

I've been working towards finishing off my project for increasing the speed of 
the Model T laptops.  The idea is to create a (relatively) easy to make and 
install solution that allows the user to switch the clock rate from 2.5 MHz to 
5 MHz.
This is really nice on the 40x8 LCD machines.

The universal software command to switch clock rate is
OUT 85,1 for 2x mode and
OUT 85,0 for 1x mode.

Of course the Model T is not designed for this, but in my experience so far, it 
seems reliable.  I really like the upgrade and plan to install in all my 
laptops. Being able to operate in nominal clock mode is of course very useful 
because you may find some software to be incompatible.

Models I have upgraded to date:
* M100 (NA, early variant, not UK)
* T102
* T200
* NEC PC-8201/8201a
* Olivetti M10

I am publishing all the information needed to DIY this upgrade. I don't have 
any plans to make these upgrades.  Consider this upgrade only if you are 
comfortable with soldering surface mount parts, and with making minor 
modifications to your laptop.

Upgrades that are done and in the process of documentation are M100, T200, NEC. 
 Upgrades that need a new PCB design still are T102 and M10.  All information 
will be at this site:

https://bitchin100.com/wiki/index.php?title=5MHZ_upgrade_for_Model_T

I am publishing
* PCB designs for the clock doubler board (there are a few variants)
* schematic
* bill of materials for parts you need
* documentation for building the clock doubler
* installation documentation per laptop

Things I have discovered while developing this;
1.  Power consumption goes up by about 20% when you run at 2x clock.
2.  Depending on the speed of your SRAM,  you may need to implement a 
modification to speed that up.  Each model has a specific mod you need.
3.  In M100 with the custom socket pinout, in most cases you need to upgrade 
your Main ROM to something faster.  This usually involves an adapter board and 
an EPROM.
4.  In the Tandy 200, one must slow down the machine temporarily to access the 
RTC.  There is a specific change for that.

Anyhow, as I complete a particular laptop, I'll post the needed files.

Hopefully this will be of some interest for those inclined to play around with 
hardware.  I have no problem if anyone wants to take the design and improve it 
or change it.

Feel free to contact me directly with questions.

cheers
Steve

Re: [M100] Jeff's dog

[birt_j]

Little Bit is a sweetheart, she is a very good dog. I don’t let the cat, Mr. 
Gus,  into the shop anymore as he likes chewing on wires and stealing small 
things. USB cables and my Surface charging cable are his favorite 😊

 

Jeff Birt (Hey Birt!)

 

From: M100  On Behalf Of Daniel L
Sent: Wednesday, November 29, 2023 12:12 PM
To: m...@bitchin100.com
Subject: [M100] Jeff's dog

 

Jeff -

I am currently watching your video on replacing the foil and foam on your model 
2 keyboard and have to say you have a cute dog.

D

Re: [M100] Model T clock doubler

[Stephen Adolph]

Had to do a minor responsibility!  Will post in a week.

On Wednesday, November 29, 2023, Ken St. Cyr  wrote:

> Hey Steve -
>
> I went to grab the gerbers from the upgrade page in the wiki, and the
> links aren't working. Would you mind sharing the file for the M100 board?
>
> Thanks!
> //Ken S.
> --
> *From:* M100  on behalf of Stephen
> Adolph 
> *Sent:* Saturday, November 18, 2023 10:54 AM
> *To:* m...@bitchin100.com 
> *Subject:* [M100] Model T clock doubler
>
> Hi everyone,
>
> I've been working towards finishing off my project for increasing the
> speed of the Model T laptops.  The idea is to create a (relatively) easy to
> make and install solution that allows the user to switch the clock rate
> from 2.5 MHz to 5 MHz.
> This is really nice on the 40x8 LCD machines.
>
> The universal software command to switch clock rate is
> OUT 85,1 for 2x mode and
> OUT 85,0 for 1x mode.
>
> Of course the Model T is not designed for this, but in my experience so
> far, it seems reliable.  I really like the upgrade and plan to install in
> all my laptops. Being able to operate in nominal clock mode is of course
> very useful because you may find some software to be incompatible.
>
> Models I have upgraded to date:
> * M100 (NA, early variant, not UK)
> * T102
> * T200
> * NEC PC-8201/8201a
> * Olivetti M10
>
> I am publishing all the information needed to DIY this upgrade. I don't
> have any plans to make these upgrades.  Consider this upgrade only if you
> are comfortable with soldering surface mount parts, and with making minor
> modifications to your laptop.
>
> Upgrades that are done and in the process of documentation are M100, T200,
> NEC.  Upgrades that need a new PCB design still are T102 and M10.  All
> information will be at this site:
>
> https://bitchin100.com/wiki/index.php?title=5MHZ_upgrade_for_Model_T
>
> I am publishing
> * PCB designs for the clock doubler board (there are a few variants)
> * schematic
> * bill of materials for parts you need
> * documentation for building the clock doubler
> * installation documentation per laptop
>
> Things I have discovered while developing this;
> 1.  Power consumption goes up by about 20% when you run at 2x clock.
> 2.  Depending on the speed of your SRAM,  you may need to implement a
> modification to speed that up.  Each model has a specific mod you need.
> 3.  In M100 with the custom socket pinout, in most cases you need to
> upgrade your Main ROM to something faster.  This usually involves an
> adapter board and an EPROM.
> 4.  In the Tandy 200, one must slow down the machine temporarily to access
> the RTC.  There is a specific change for that.
>
> Anyhow, as I complete a particular laptop, I'll post the needed files.
>
> Hopefully this will be of some interest for those inclined to play around
> with hardware.  I have no problem if anyone wants to take the design and
> improve it or change it.
>
> Feel free to contact me directly with questions.
>
> cheers
> Steve
>
>
>
>
>

[M100] Jeff's dog

[Daniel L]

Jeff -

I am currently watching your video on replacing the foil and foam on 
your model 2 keyboard and have to say you have a cute dog.


D

Re: [M100] Model T clock doubler

[Ken St. Cyr]

Hey Steve -

I went to grab the gerbers from the upgrade page in the wiki, and the links 
aren't working. Would you mind sharing the file for the M100 board?

Thanks!
//Ken S.

From: M100  on behalf of Stephen Adolph 

Sent: Saturday, November 18, 2023 10:54 AM
To: m...@bitchin100.com 
Subject: [M100] Model T clock doubler

Hi everyone,

I've been working towards finishing off my project for increasing the speed of 
the Model T laptops.  The idea is to create a (relatively) easy to make and 
install solution that allows the user to switch the clock rate from 2.5 MHz to 
5 MHz.
This is really nice on the 40x8 LCD machines.

The universal software command to switch clock rate is
OUT 85,1 for 2x mode and
OUT 85,0 for 1x mode.

Of course the Model T is not designed for this, but in my experience so far, it 
seems reliable.  I really like the upgrade and plan to install in all my 
laptops. Being able to operate in nominal clock mode is of course very useful 
because you may find some software to be incompatible.

Models I have upgraded to date:
* M100 (NA, early variant, not UK)
* T102
* T200
* NEC PC-8201/8201a
* Olivetti M10

I am publishing all the information needed to DIY this upgrade. I don't have 
any plans to make these upgrades.  Consider this upgrade only if you are 
comfortable with soldering surface mount parts, and with making minor 
modifications to your laptop.

Upgrades that are done and in the process of documentation are M100, T200, NEC. 
 Upgrades that need a new PCB design still are T102 and M10.  All information 
will be at this site:

https://bitchin100.com/wiki/index.php?title=5MHZ_upgrade_for_Model_T

I am publishing
* PCB designs for the clock doubler board (there are a few variants)
* schematic
* bill of materials for parts you need
* documentation for building the clock doubler
* installation documentation per laptop

Things I have discovered while developing this;
1.  Power consumption goes up by about 20% when you run at 2x clock.
2.  Depending on the speed of your SRAM,  you may need to implement a 
modification to speed that up.  Each model has a specific mod you need.
3.  In M100 with the custom socket pinout, in most cases you need to upgrade 
your Main ROM to something faster.  This usually involves an adapter board and 
an EPROM.
4.  In the Tandy 200, one must slow down the machine temporarily to access the 
RTC.  There is a specific change for that.

Anyhow, as I complete a particular laptop, I'll post the needed files.

Hopefully this will be of some interest for those inclined to play around with 
hardware.  I have no problem if anyone wants to take the design and improve it 
or change it.

Feel free to contact me directly with questions.

cheers
Steve