Thanks for your support. So 16F84 should be Ok. But it is not. Pickit2 (EDU10) shows “no device detected” and DEVICE "unsupported part (ID=3FE0).
I am using an adaptor connected to J2 which connects all 5 lines (MCLR, ICSPD,ICSPC, Vdd & Gnd) to appropriate pins on 16F84 - checked and re-checked. Maybe my 16F84 is a dud. I shall obtain 16F84A and try again.