Regarding Philippe's ESCR-RSU-2 and mine.
I finally understood how they should work.
This model is a 64K RSU version.
Ordinary Eramco models have 6 outdoor switches.
Those have only 2 indoor switches :
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Disable Writing <- [SW1] -> Enable Writing
Enable 32K Bank #1 <- [SW2] -> Enable 32K Bank #2

Alas both are out-of-order.
The first one is only 12.5% functional and the other one is dead.
Regarding the first RSU-2, only pages E and F in bank #1 are available.
I used ES-RSU1A/2A (ES-41 Data Base 85), Hepax 1B/1C/1D, David Assembler Rom, Rambox (32), ES-MLDL OS, MLDL OS, ...
Always the same result... :o(
Thanks in any case for your mails.
I send a message to Philippe.


Dear Emmanuel,

one question about the both internal switches of the Eroamco RSU : SW1 would be used for protecting the internal operating system. Is it correct, that SW2 only would needed for loading the internal operating system to bank #1 and bank #2 ? Because when the oerating system is stored to the RSU bankswitching would be realised by software commands...

May be you are able to fix the hardware failures of the RSU, by exchanging the chips with new chips. But I do not know if this special storage chips are available today...

With best regards - Christoph Klug



You could also try to send a mail to the designer of the Eramco ESCR-RSU: Martin Lennarts in the Netherlands. Maybe he still remembers.


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