Data communication between PC to PC requires communication software etc. If you use pin other than connection picture pin, it cannot be used. For PC-9800 series <=> PC98-NX, PC-9800 series <=> PC/AT, use cable connection of Windows 98/95.
Compatible machine and corresponding (architecture) PC / AT compatible & PC98-Nx corresponding & PC9821.PC9821
DOS / V PC D-Sub9pin female - NEC PC-9800 series D-Sub25pin male
Cable Length (m)
(Model with an RS-232C interface of D-Sub9 pin) companies DOS / V personal Con NEC PC98-NX series PC-9800 series, and EPSON PC series, etc.