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Commodore m55, anyone got one?
05-18-2018, 01:02 PM (This post was last modified: 05-19-2018 07:36 AM by blackjetrock.)
Post: #1
Commodore m55, anyone got one?
I have finally got my hands on a Commodore m55, albeit in broken form when I got it. I fixed it up and got it working, I have a video here if you're interested:

https://youtu.be/HOy0yVGiYTk

Now, I got the calculator going and was trying various things out and I got to the gallons/litres conversion function. When I converted 1 gallon to litres I got the expected answer: 4.54 or so. Hmm, hang on a minute, that's the expected value for me as I'm in the UK. I checked the manual and the figure it quotes for the conversion is 3.7854 or so. So my calculator doesn't agree with the manual. I'm pretty sure my calculator was a UK purchased one so it has a US value in the manual and a UK conversion factor. Does anyone over in the US have a Commodore m55? Could you try converting a gallon to litres and see what you get?

I didn't notice a jumper to switch US/UK on the PCB but there could have been, I suppose. Are there any internal photos of US m55s on the web anywhere?

Does this mean I don't have a complete set of 60 series Commodores?
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05-19-2018, 07:07 AM (This post was last modified: 05-19-2018 07:09 AM by EdS2.)
Post: #2
RE: Commodore m55, anyone got one?
Those are amazing keyboards!

Makes sense to me that a Made in England calculator would have UK conversions: it would be a bug otherwise! Commodore made their own chips, so the constants would be in their own mask ROM - they could conceivably have a bond out option, or a tie off, but I wouldn't be surprised if there was a US ROM - if indeed this calculator was ever sold in the US.

BTW I think you meant to link this video:
https://www.youtube.com/watch?v=HOy0yVGiYTk

Cheers
Ed
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02-03-2019, 09:29 PM
Post: #3
RE: Commodore m55, anyone got one?
There's one up for sale on TAS at the moment. Untested, but excellent cosmetic condition. (Which probably means the Ni-Cd battery pack will have leaked all over the insides!)

— Ian Abbott
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02-04-2019, 09:07 PM
Post: #4
RE: Commodore m55, anyone got one?
(02-03-2019 09:29 PM)ijabbott Wrote:  There's one up for sale on TAS at the moment.

That makes already two because I saw one on eBay. High on my wish list but a little on the expensive side for an "untested" (=broken) unit.
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02-04-2019, 10:24 PM (This post was last modified: 02-04-2019 10:25 PM by ijabbott.)
Post: #5
RE: Commodore m55, anyone got one?
(02-04-2019 09:07 PM)Maximilian Hohmann Wrote:  
(02-03-2019 09:29 PM)ijabbott Wrote:  There's one up for sale on TAS at the moment.

That makes already two because I saw one on eBay. High on my wish list but a little on the expensive side for an "untested" (=broken) unit.

The same seller also has a listing for an even more expensive (and also untested) Commodore S61, but that one comes with the original cardboard box (but no PSU!).

— Ian Abbott
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07-11-2020, 08:41 PM
Post: #6
RE: Commodore m55, anyone got one?
This conversation might have moved on but I have an M55, N60 and S61. If anybody can point me towards instructions, I'll take the back off. If all is good and you're interested then I'll stick it on ebay or any service where it would give you comfort that the items will actually turn up (gumtree?) 8-)
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