41CL Foolish Blunder


Hi, I have committed a really foolish blunder with regards my newly acquired 41CL.
Without looking properly, I used Geoff's YCTOF program to back up my RAM. As a result I have
erased some of the solution books starting at address 0C9000. :(
I don't have Clonix or any other hardware, only the serial port on the 41CL.
Is it possible to update the flash with these ROM's (from TOS) via the serial port?
Do the ROM's have to be modified in any way?
I would be using Raymond Wikers software to download.
Really bad mistake, but you live and learn the hard way if you don't read properly at first!
Looking forward to help and advice.
Best Regards


Greetings John, yes I think it's possible to update the Flash. You'd first need to upload the module images to CL RAM using the Serial connection, and then burn the flash sector (8 blocks in total, doesn't do anythink smaller).

What reminds me, there are a couple of those ROM images that were updated after their addition to the CL board, so you could just as well use the new ones.

Good luck, and make sure you have fresh batteries when doing any Flash burning!

Edited: 29 May 2012, 10:12 a.m.


Thanks for replying Angel
Do the ROM's need to be modified in any way?
I don't "think" so (but I am really a novice with the 41CL) because as I understand, the image database
contains pointers to the addresses of the modules, so it knows which to load.
What about the four letter CL mnemonics (eg A41P,CURV etc). Are these in the image database?
Thanks once again. I am really angry with myself for not checking first!
Best Regards


Do the ROM's need to be modified in any way?

Not at all, once they´re in RAM (either via serial link or Clonix) they´re ready to go to Flash.

What about the four letter CL mnemonics

Completely transparent to the issue - they´ll work as before, no need to worry about it.

I can send you the new ROM images, just email me your email address.



Hi John,

Sorry for the mix up between the versions. As a beta user I created YCTOF for the CL ver. 1

As you now know (unfortunately) YCTOF must be modified for version 3. I must admit that I have not updated YCTOF too reflect Montes changes with the addition of even more ROM images which now occupy the free user RAM on version 1. It would appear that you overwrote ISENE ROM if you only used the OC9 as a backup.

Now a CLONIX could be used to replace the image or the serial. I have not been using the serial or playing much with the CL for a while as home life is extremely busy. If you do get the serial to work would you mind posting a step by step set of instructions including the software used and your operating system.

I am not in possession of a ver. 3 so this was a surprise.

So a caveat for all you CL users with version 3. YCTOF program must be modified to reflect the free user RAM available on your version:


Version 1. OC9 is free for use and of course check the manual.
Version 3. 118 appears to be the first 'user RAM' that is available for a flash backup.

I guess I need to get version 3! I am thinking that Monte would be able to send you a copy of the ROM images complete with the labels as they appear in the CL version three. Try emailing him directly.

Cheers, Geoff

Edited: 29 May 2012, 12:39 p.m.


I believe the labels are not stored with the ROM images, but are in a separate table somewhere.


Yes you are correct Howard. I asked Monte the question as to whether I needed to modify ROM labels,
and he said it was not necessary. The image database contains the links/addresses to the modules.
Best Regards

Edited: 29 May 2012, 1:51 p.m.


Hi Geoff, thanks for the reply. Unfortunately more than just the ISENE ROM is gone, as a YFERASE, erases 32k words.
Anyhow, I will certainly be more careful in future. Thanks for your input and for all
your other contributions to the forum, which certainly have helped me.
Best Regards


Hey there. Don't be too hard on yourself. Given my blunder of the recent garage door battery fiasco with my 28S from last week, you're okay in my book.

Edited: 30 May 2012, 1:49 a.m.


Thanks Matt,but this was really a foolish mistake as I am normally very careful.
Thanks to everyone that replied to my post. Appreciated.
Best Regards


You're welcome. I hope you get the CL back to its regular self.


The Secret of Happiness

Nasrudin is known as much for his wisdom as his foolishness, and many are those who have sought out his teaching.

One devotee tracked him down for many years before finding him in the marketplace sitting atop a pile of banana peels--no one knows why.

"Oh great sage, Nasrudin," said the eager student. "I must ask you a very important question, the answer to which we all seek: What is the secret to attaining happiness?"

Nasrudin thought for a time, then responded. "The secret of happiness is good judgment."

"Ah," said the student. "But how do we attain good judgement?"

"From experience," answered Nasrudin.

"Yes," said the student. "But how do we attain experience?"

"Bad judgment."

- The Beggar King and the Secret of Happiness by Joel Ben Izzy, Algonquin Books of Chapel Hill, 2003

So let's just say you have attained some experience, something I am sure some of us are familiar with.

And on the positive side, you're a step closer to happiness ;-)



Hi Bart, very eloquently put. I think that when a mistake like this is made, one is overwrought with
frustration at oneself, when one knows better.
Best Regards


I know, like the time I tried to measure the voltage of a 110V 100Ah lead-acid battery - and found I had accidently put the +Ve probe in the Amp socket of the multimeter. That was many years ago and the resulting flash is still etched in my brain! Although the multimeter is equipped with a 10A fuse, the instantaneous current is much higher - the probe was about 5mm shorter and there was a hole where I had touched the lug of the connecting cable. Amazingly the multimeter survived and all it needed was a new fuse (but I decided not to fit that fuse for future safety).


That would have been some flash!

Perhaps my stupidest electronic blunder was while extending the cord for one of my pieces of ham equipment. The cord was too short, so I figured I would just splice in a length of two-conductor wire. I carefully unplugged the original cord from the chassis, completely forgetting to unplug it from the 110 VAC wall socket. I then proceded to cut it with my wire cutters - FLASH! For the last 45 years, the pair of half-moon melted-out spots on one of the cutter blades have reminded me not to do this again!

This of course does not include the time I bypassed the elevation drive switch on a 15-meter satellite dish so that I didn't have to hold it down while it moved (slowly!! fraction of a degree per minute) to my desired next position for a radio source calibration observation. 15 minutes later, after I forgot about it, somebody noticed that the limit switch had been reached. I have forever been thankful to the designer who planned for some idiot to manage to reach the limit, and saved me from a several million dollar repair bill!


In my early days as a computer repair tech, I was working on an old banking terminal that had linear power supplies that where fed by transformers with resonant winding which is an extra winding that is connected to an AC capacitor to provide a level of line regulation. The machine I was working on had no output from one of the transformers, and having already been caught by a shorted capacitor I disconnect the capacitor to see if it was the problem and sure enough with it disconnected there was output from the transformer. Now I should have stopped there and just got a new capacitor, these machines where not picky about voltage and would continue to work even if the DC drifted a few volts either way. but I thought I would reconnect it just to make sure it was the problem well by now the capacitor had cooled off and when reconnected I still got output from the transformer. But I reasoned that it must be going short when it warms up so to keep the bank working I decided it would be best to disconnect it until I could get a replacement.

Now where I am working on this is behind the control unit which is about the height of a desk and has one of the printer keyboard unit sitting on top of it and on either side of it are other cabinets and there is a space of about 4 ft between the back of the machine and the wall, in front of the machine there is about a 6 ft isle and then the customer counter. After I disconnected it I thought this capacitor is going to be charged up now and I thought I better discharge it before leaving with it, well was it ever charged! There was a loud crack and a blinding flash followed by a number of concerned people looking over the top of the cabinets asking if I was ok. It welded the shank of the screwdriver I had used to discharge it to one of the terminals, and there was a sizable burn near the other terminal. I carried that screwdriver in my tool bag for quite a while as a reminder.

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