Hi, I noticed a lot of you have experience with the Keil compiler, with which I can get code for the 89c668 working very good.
Reasonable large source, including i2c to different devices, serial communication with a Motorola M18 etc.

However, I needed to modify the startup.a51 to disable external memory (the 668 has 64K flash, and 8Kb ram) to get things working, no problems here.

When using sdcc, I've created the _sdcc_external_startup() function, where the EXTRAM bit is cleared, no problems here either.

Anyway, it looks like the sdcc compiler produces code which crashes. This would probably be a problem with the stack, but my knowledge about this processor is too limited to fix this.

Does anyone have pointers how I should setup the xram-loc, iram-size, stack-loc, code-loc etc with this processor?
I've read the 8051 memory faq at turbobit.com, and the sdcc manual, but it doesn't help me much.

When compiling the code in model-large, with stack-after-data, it produces code where the isr's are working, but after a few seconds, the main loop crashes :(

Anyone with suggestions, how I should setup these memory locations, or how to debug it?