How to get rid of SoftICE mode in P89V51RD2.


No warranty that this will work for your device.
No liability for damages, lost devices etc.
Do everything on your onwn risk.

Assuming bootloader v4 and softice mode (consequence of :00000002FE).

  • download and install Keil uVision2 (evaluation version is enough); run it
  • download unsoftice.a51
  • select Project->New Project, enter any name (e.g. "unsoftice"); a "select device for Target" window opens, select Philips->P89V51RD2, a dialog opens ("Copy Standard 8051 startuop code...") answer No
  • select File->Open, select unsoftice.a51; file should open
  • select Project->Components,Environments,Books, a window opens, in Project Components select Add Files, enter/browse unsoftice.a51
  • select Project->Build target, in the bottom (Outputs Window) it should write
     0 Error(s), 0 Warning(s).
  • select Project->Options for Project, Option for Project window opens, select tab Debug, select in the right column on top Use: Keil Monitor-51 driver, don't change anything else (unless the target device is not on COM1 - in that case modify it in the Options), click OK (window closes)
  • select Debug->Start/Stop debug session (in evaluation version a nag window EVALUATION VERSION (code limit 2k) opens, click OK), the windows rearrange a bit
  • select Debug-Go (nothing really happens), clicking on the red "Stop" button should bring a window saying something like "Can't stop application because serial interrupt is disabled". Click Stop debugging, wait for a moment until window "Connection to target lost" appears, click Stop Debugging.
  • you can exit Keil uVision2.

At this moment, the original state of bootloader is (hopefully) already restored.


- run your favorite terminal emulator, set 9600/8/n/1 NO_handshake. Switch CAPS LOCK ON (check led CapsLock on keyboard) and hold U (for autorepeated capital U). Reset the target (or switch off/on) while holding U. In a while, it should echo back the U's. Now try typing
it should echo what you type and when typing in the last character (="9") it should echo 2 more characters, a fullstop and a carriage return, so the echo should look like:

Now you can upgrade the bootloader to version 5 (can be found on Philips website) or try some other bootloader modification...

31/01/2005 - wek at efton dot sk