Expansion serial card?

[Dave]

Did anyone ever make an expansion serial card for the QL? I've never seen one, but I have heard mention of one existing.

If one does, I am very open to buying or borrowing it to understand it and to see what code the ROM contains. I am trying to solve a big problem and the built in QL serial just isn't up to the job.

[janbredenbeek]

Did anyone ever make an expansion serial card for the QL? I've never seen one, but I have heard mention of one existing.
If one does, I am very open to buying or borrowing it to understand it and to see what code the ROM contains. I am trying to solve a big problem and the built in QL serial just isn't up to the job.

Long before Hermes came along I built a serial interface for the QL using a 6850 ACIA. It was very primitive to modern standards, using manual switches to set the baud rate and the 6850 could buffer only one byte. But it could drive dumb 1200/75 bps modems flawlessly, unlike the QL's serial ports. The driver software was loaded from RAM (timing was not critical since the 6850 has its own shift registers). One big drawback of the 6850 was that a loss of DCD (carrier detect) signal completely shuts off the receiver, which makes it difficult to receive status messages from Hayes-compatible modems unless you keep DCD constantly enabled (which is undesirable when running a BBS service). I sold it long ago since it occupied the expansion connector, which I couldn't use for memory/disk expansion.

Instead of building an entire new interface, you can replace the QL's 8049 IPC with Hermes or superHermes. This cures most serial problems, including overruns, bad reception and inability to use split baud rate. I'm sure there's someone on this forum who is willing to sell you one - perhaps Tony Firshman still has some in stock?

Jan.

[Dave]

Hermes and SuperHermes will be far too slow for my needs. I'd consider something like maybe I2C or SPI too if it's working and *fast* to copy something from it to RAM.

The idea is to connect a wiznet device to enable 10/100 ethernet, with the stack running on an outside device since the 68EC020 and similar devices are far, far to slow to properly run a useful TCP/IP stack.

[Derek_Stewart]

Hi Dave,

Terry Harman did a Fast Serial board for the QL, which I beoiee Phil Borman used on his BBS for Fido Net mail.

The PCB and Rom files are on Dilwyn's Web Site.

[Ralf R.]

Hi Dave,

Terry Harman did a Fast Serial board for the QL, which I beoiee Phil Borman used on his BBS for Fido Net mail.

The PCB and Rom files are on Dilwyn's Web Site.

Just found a COM driver update.

[Dave]

Hi Dave,

Terry Harman did a Fast Serial board for the QL, which I beoiee Phil Borman used on his BBS for Fido Net mail.

The PCB and Rom files are on Dilwyn's Web Site.

I will search for this and post the link here. Others may be interested too.

[Derek_Stewart]

Hi Dave

I may of been mistaken.

The only file I could find was an updated Ser driver.

However, I have the files necesdary to make the serial board.

I will update Dilwyn with the files in the morning. Just drinking wine and watching England beating Germany at football....

[Paul]

Just drinking wine and watching England beating Germany at football....

You really saw England beating Germany? You better stop drinking English wine and start drinking Scottish whisky then
By the way, I haven't seen it. Been told it's been the worst game in decades. You better had sent the files instead of wasting your time
kind regards Paul

[Derek_Stewart]

Hi Paul,

I have the files, found them last night during the first half...

There is PCB files in various PCL, HPGL formats and JED definitions.

I will send them to Dilwyn for publication on this web site.

With regards to the football game, England out played Germany, but due to a lucky goal, Germany won the game.

Not the best game of football I saw and probably not the best German team, there has been better.

Wish I had more then 2 glasses of wine...

[Derek_Stewart]

Hi,

I have sent Terry Harman's Faster Serial board PCB files to Dilwyn for central distrubution.

Here is a description by Terry in 1993, about the serial board:

With the advent of affordable modems and telephone lines that can support high
speed data transfere, the QL's slow serial port has become a major bottleneck
for anyone who is into comms.

For optimum performance the user sets his serial port to the highest speed that
his modem supports. For most 150 pound modems this is now 57600 bits per sec.
At 9600 bits per sec, the QL serial port is 6 times slower than the modem can
cope with, hence the bottleneck.

The latest Modems ( next years 150 pound jobs ) are running at 115200 bps.

Before you chuck the QL out of the window and rush off to Dixons for the latest
super wizzo IBM look-alike, you might like to know that it cann't cope with over
38400, unless you flash out another 100 quid on a fast serial card.
With a Fast serial card and a standard QL you can blow the socks off them today,
and cope with tomorrows 115200 ( and faster ) with ease.


| QL 1 |----|MODEM 1 |--Telephone line---| MODEM 2 |----| QL 2 |--|Disk Drive|


QL 1 sends and recieves data to Modem 1 via its serial port.
The speed is set by the speed of QL 1's serial port.

Modem 1 and Modem 2 send and recieve data via the telephone line.
The speed is set by Modem1 and Modem2 negotiating the fastest speed they
can both cope with.

QL 2 sends and recieves data to Modem 2 via its serial port.
The speed is set by the speed of QL 2's serial port.

I have had to slightly modify the foramt of the ASCII art in the diagram.