Hi Bert,

mabe, the best was to switch to the T89C51CC01 (Atmel Wireless).
It looks nearly similiar to the C505 (clock / 6, internal ADC, PCA, CAN) but with one exception: Its not OTP, its already 32kB Flash.

Also there is a bootloader included to be able to solder the unprogrammed device and download the application via UART or CAN after this.
The 2kB bootloader can also be altered with an external programmer, but was protected against the in application programming routines. So only the lower 32kB can be programmed in application and the bootloader was secured.

Really nice device.

Peter