Xport robotics

Is it time to revive that old project I never finished, or do I abandon it and start a new robot using an ATOM mini itx?

To stay with the XPORT/XRC I need to be able to modify the XRC digital IO port to something more useful, e.g. I2C, PWM, etc.  I have no yet learnt verilog, but intend to do so (given a purpose), so not to sure if it is possible.  I have been looking at robot1.v, the section for “// XIR sensors”, and think this is the area I need to adapt.  Is this possible, and what are the first steps?

I have been reading up on verilog, and getting familiar with the xrc logic.  I believe the answer to my question is, yes it is possible to change the use of the "XIR Sensor" pins.

I have successfully synthesized, implemented, and generated a programming file (.bit) using robot1.v.  I had some problems, which think may be because I was using ISE 10.1   There were some errors (see below) when I was implementing the design, to fix these I deleted the unused NETs from the ucf file.

The next stage is to remove the xir sensor logic, and instantiate an instance of the PWM module.



ERROR:ConstraintSystem:59 - Constraint <NET RData<0> LOC = P161;>
   [robot1.ucf(167)]: NET "RData<0>" not found.  Please verify that:
   1. The specified design element actually exists in the original design.
   2. The specified object is spelled correctly in the constraint source file.

I am not so sure deleting NETs from the ucf file to clear errors was the correct thing to do?  I just noticed that I had deleted <NET RCs LOC = P45;>, which is needed to enable/disable SDRAM.

Would the correct thing to do be drive them to something like <assign RData[0]  = 1'bz;>?

This is a list of the NETs I deleted, they look like they are used for SDRAM.
NET PB<0> LOC = P97;
NET PB<1> LOC = P96;
NET PB<2> LOC = P95;
NET PB<3> LOC = P94;
NET PB<4> LOC = P90;
NET PB<5> LOC = P89;
NET PB<6> LOC = P88;
NET PB<7> LOC = P87;
NET PB<8> LOC = P86;
NET PB<9> LOC = P84;
NET PB<10> LOC = P83;
NET PB<11> LOC = P82;
NET PB<12> LOC = P81;
NET PB<13> LOC = P75;
NET PB<14> LOC = P74;
NET PB<15> LOC = P73;
NET PB<16> LOC = P71;
NET PB<17> LOC = P70;
NET PB<18> LOC = P69;
NET PB<19> LOC = P68;
NET PB<20> LOC = P67;
NET PB<21> LOC = P63;
NET PB<22> LOC = P62;
NET PB<23> LOC = P61;
NET PB<24> LOC = P60;
NET PB<25> LOC = P59;
NET PB<26> LOC = P58;
NET PB<27> LOC = P57;
NET PB<28> LOC = P49;
NET PB<29> LOC = P48;
NET PB<30> LOC = P47;
 
                 
NET RData<0> LOC = P161;   
NET RData<1> LOC = P160;   
NET RData<2> LOC = P107;   
NET RData<3> LOC = P154;   
NET RData<4> LOC = P70;   
NET RData<5> LOC = P96;   
NET RData<6> LOC = P48;   
NET RData<7> LOC = P57;   
NET RData<8> LOC = P67;   
NET RData<9> LOC = P62;   
NET RData<10> LOC = P60;   
NET RData<11> LOC = P58;   
NET RData<12> LOC = P49;   
NET RData<13> LOC = P47;   
NET RData<14> LOC = P46;   
NET RData<15> LOC = P44;   
NET RAddr<0> LOC = P84;   
NET RAddr<1> LOC = P87;   
NET RAddr<2> LOC = P89;   
NET RAddr<3> LOC = P94;   
NET RAddr<4> LOC = P95;   
NET RAddr<5> LOC = P90;   
NET RAddr<6> LOC = P88;   
NET RAddr<7> LOC = P86;   
NET RAddr<8> LOC = P83;   
NET RAddr<9> LOC = P81;   
NET RAddr<10> LOC = P82;   
NET RAddr<11> LOC = P74;   
NET RBs<0> LOC = P73;   
NET RBs<1> LOC = P75;   
NET RRas LOC = P68;   
NET RCas LOC = P63;   
NET RCs LOC = P45;   
NET RWe LOC = P61;   
NET RLdqm LOC = P59;   
NET RUdqm LOC = P69;   
NET RCke LOC = P71; 

THANKS for the info....