tried everything for isp-89v51

[sarat]

hi

i'm using P89v51rd2.i'm unable to engage the isp mode. i tried repeatedly reseting & also switching on /off the circuit. i had selected the right device. tried changing the baud rates too.nothin seems to work. i'm using a printed kit board which originally supported AT89c51 & have kept p89v51rd2 into it.

[erikm]

My guess is that you have the abnomiable RC reset.  Any circuit without a supervisor is asking for it.

Erik

[Jan Waclawek]

The chip may be in the SoftICE mode. You can check it this way: get a terminal program capable of sending binary/hex characters (e.g. term by bray). Power on your board and send 11h ($11) mulltiple times. If the chip responds alternating $00 and $FF, then it is in SoftICE mode.

Jan Waclawek