Hey all I want to access the serial port D before the rs-232 converter I just want to make sure it is safe to apply the 3.3ttl using the pin PC1 on the header without burning up the converter.
I am assuming you are working with the supplied development board for the RCM4010. There are 0 ohm resistors used as jumpers on the RCM4xxx development board. If you remove the resistor marked JP5 it will isolate PC1 from the output of the onboard RS232 transceiver leaving it open to work at TTL levels. First you will need to remove the core module from the development board. Now, if looking at the development board with the battery positioned to the top, so you can read the markings for the unstuffed J2 connector, then RP5 will be to the left of the core module connector, just under IC U2. Not the easiest change to make, but better than cutting traces. Remember that once you remove this resistor, the RXD line will no longer work through the RS232 transceiver without replacing this resistor.
Thanks. Got it to work after figuring that out.