does anyone know how to interface this Gt3721 or similar gps using ps2 port ?
please help me with the pin diagram of the port
and corresponding pin diagram in PC side using serial port
and the interfacing circuit required (voltage level converters) if needed to interface it with PC
It seems that connecting that gps receiver is not possible without using an advanced interface. There are two problems: different voltage levels and different protocol. You must use a "smart" interface (with a microprocessor) that will translate RS-232 to the PS/2. There is a possibility that such a interface is commercialy avaible. Or you can build such a circuit, here is an example: **broken link removed** (don't forget to add extra level converter based for example on MAX232).
BTW: I think that device should work: The VIP-335 RS-232 to PS/2 Keyboard Protocol Converter from Vetra Systems, The Industry's Broadest line of KVM Products