Also FTDI makes a cable that integrated the converter chip in the USB connector. USB on one side, 5V TTL on the other. Just add resistors, splice in an RJ11 or RJ12 and you're good to go. I just did one and it worked fine, although I didn't need the f/w upgrade.

http://www.ftdichip.com/Products/EvaluationKits/TTL-232R.htm

Todd G

Hell to all,
some good news here for me. But with some questions.
What is the cheapest way to upgrade my firmware.
I don't want (I am not able) to make something like this http://www.autopano.net/wiki-fr/action/ … matic1.png. Isn't some simplier solution how to connect PC with Merlin only to make the firmware upgrade? (I still have PC with real Serial port).

The link i posted suggests that all you need is a MAX232 and 5 capacitors to convert to TTL from a regular serial port, not the much larger circuit above, I would (and will) buy those 6 components first and try that, they total less than $2.00. The important bit - the 12V to 5V drop - is completely handled by the MAX232 so the worst that can happen is you don't get decent comms established, you aren't going to break anything by trying the simpler circuit first. If it doesn't work fully you can add on the extra components to make the larger circuit.

Usual disclaimer: your mileage may vary and i'd have someone else confirm that assessment first as I haven't dealt with TTL since high school.

Hello Merlin users,

We (Together with Teleskop-Austria) are in contact with Synta, and I try to help them to modify their Firmware uploader program to operate with our bluetooth interfaces.

Tamas

Hello!

I've made a test, the Merlin updated successfully.

I used a FTDI based interface cable. Mine is similar than yours, but instead of 220 ohms, I use 470 ohms.
I updated the merlin with program downloaded from Teleskop-Austria.
After updated, the Merlin works well, I doesn't noticed the positioning and speed problem!

Tamas

Hello Claude,

I can suggest you a third option:

I try to help Synta to improve their uploader program to work it with our bluetooth modules.
If we can do it, it should be the third (and hopefully the best) option.

Tamas

Hi,

Firmwareupdates via bluetooth ?
I can't recommend this.
If we have a safe and wired connection the possiblity of an aborted firmware upgrade is minimized.
With bluetooth we have much more possible failures.

Regards,
Volker

Hello all.

I have try the Update today with a FTDI based interface cable and TA Update Software, no Problem. Terminal now say me the new Version is loadet on the Merlin.(:e1) Hope for better Weather to try it Outdoor. :-)

Patrick

Hi,
I just made the update from "bad" to "good" with a real serial adapter (max232) with no problems. With the old firmware I had to wait a couple of seconds before the motor reached the next position, now it's working much faster...

Thank you Claude and Tamas for your effort!

Manfred

This MAX232 based kit seems like a good buy for those in Canada/US who are confident enough with a small amount of soldering

S232 TTL Convertor, Adapter Kit MAX232, $6.99
http://www.ecrater.com/product.php?pid=3528372

They have another one as well http://www.ecrater.com/product.php?pid=3527176 but its more expensive and doesn't seem to contain a chip so I am not quite sure how that one would be any better.

Hello Gordon,

I'm just wondering if this update will work on the original merlin

NO!
The original Merlin has another Motor controler board and should no be updated !

ALL MERLIN WITH FIRMWARE VERSION 01.##.## like the 010581 (01.09.81) SHOULD NOT BE UPGRADED WITH
VERSION 02.##.## !!!!!!
This upgrade could disturb completely your head and it can be IRREVERSIBLE !!!

and would there be a speed increase

NO !

is it only a firmware update for the new merlin ?

YES !
Only for Merlin with VERSION 02.##.## Firmware like the 020581 (02.05.81)
Thats the reason why we have launched the inventory.
According the production periods, we have established that all Merlin before July 2009 have a firmware version 01.##.## like the 010581.

So in your "personal" case, your Merlin have the firmware 010581 wich is a VERY GOOD one !!!
Don't change it !!!

I should have clarified that I already own USB-serial adapters with which to use a MAX232 adapter.

I for one feel much happier about connecting a USB-serial adapter first and then applying any home made voodoo after that rather than messing around with homebuilt circuitry directly on the USB outs of my $3000 macbook pro. I am sure i am not alone in that regard At least I am less likely to smoke the USB bus in my laptop this way, as some protection will be afforded by the circuitry in the USB-serial adapter.

Last edited by Matthew Field (2010-01-10 22:30:47)