Cable LORITEL

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rjiji
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Cable LORITEL

Post by rjiji »

Hello
Does anyone have the wiring for the LORITEL cable? (dbug for example :D )

thank.
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Dbug
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Re: Cable LORITEL

Post by Dbug »

I need to check if it can easily be opened without damaging it, else I will have to use the continuity tester.
rjiji
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Re: Cable LORITEL

Post by rjiji »

Thk dbug
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Dbug
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Re: Cable LORITEL

Post by Dbug »

I used the continuity tester to find the pin-out.

So here is what the two connectors look like:
image_2022-06-12_110910030.png
image_2022-06-12_110922051.png
And here are what the pins connect to (as seen from when you look at the cable, not the connectors on the machine):
image_2022-06-12_110934780.png
So basically out of all the 20 wires on the cables, there are only three which are used:
  • Pin 1 of the DIN is RX and connects to pin 17 (D7) on the printer port
  • Pin 2 of the DIN is the ground and connects to pin 2 (one of the 10 grounds) on the printer port
  • Pin 3 of the DIN is TX and connectors to pin 1 (Strobe) on the printer port
Kind of a waste of wires really :D

If they had chose D0 instead of D7, they could have used just 4 wires on the entire cable to make it much easier to pass in the DIN enclosure.
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kenneth
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Re: Cable LORITEL

Post by kenneth »

The cable is not grided, then I supose that the choice of d7 is a way to "separate at the farest" tx and rx to avoid radio disturbance. Beware with this adaptator: the rs232 protocol is using normally -12v +12v, this one is only compatible with the Minitel device, using a TTL level. The 6522 chip is precious... :roll:
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Re: Cable LORITEL

Post by Dbug »

The fact it's all twisted on itself to fit in the DIN plug, does that not kind of negate selecting the farthest pin?
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iss
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Re: Cable LORITEL

Post by iss »

The reason to choose D7 can be the protocol used i.e. sending MSB first, then simply ASL $0300 will do the job.
Leaving all not used wires is for aesthetic, a crimped IDC20 with missing wires looks really very ugly.
EDIT: One more thing IDC20 with only 3 wires will be very easy to tear by unpluging ;).
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kenneth
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Re: Cable LORITEL

Post by kenneth »

Image
The black connector on the left could be ideally used for this, with a shielded cable, it contains a 20pin Dupond header. It was used for the AMX mouse with the CPC computer. The shell is very difficult to find, maybe a 3d printer can solve this problem?
rjiji
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Re: Cable LORITEL

Post by rjiji »

Thk debug for the diagram
i will try this
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