I proudly own a little older computer (Pentium II, 233) and additionally now an old serial ISDN modem. (Not this modern USB stuff)
Now the modem wire ends in a 9 pin D-Sub while my computer has a 25 pin D-Sub COM 2 port (I use COM 1 instead of the PS/2 for the mouse because this highly sophisticated piece of Micro$oft operating system does run more stable with the wheelmouse on the COM 1 and the IRQ for the PS/2 disabled, otherwise I always have a blue screen when scrolling through the start menue with the wheel
)
Which pins must be connected from 9 to 25 to make the modem run ?
Transmit Data, Recieve Data, and Signal Ground as well as Protective Ground on one connector (computer side I think), but what about hardware handshake lines ? Or don´t such things exist any more ?
And which pin no of the 9 pin to be connected with which one of the 25 pin ???? I think the wire crosing is already done in the 9 pin cable, so I suppose there is no further crossing needed.
I used to work on computer hardware in the times when floppies had 8" diameter and were hard sectored and 64 kB main memory and 10 MB hard disks (5 1/4", 5 disks, 10 surfaces, two slots high) were state of the art
At that time only 25 pin connectors existed and RTS/CTS handshake was normally used.
Any hints are wellcome
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