Full Chip Simulation - unallocated variable

[SSK]

Hello forum members,

I am using Codewarrior 4.6 build 6345 for MC9S12A128 processor. I am using full chip simulation target in the debugger to test my SCI code. I have two functions for sending and receiving character to/from SCI of the device. The receive routine works correctly but for the transmit routine indicates that the variable used to hold the character is not allocated and hence it displays zero '0'. I am transmitting the same character that I receive using receive routine. I am attaching a snap of the debugger showing the unallocation of the variable. What could be the cause for this? Your earliest reply will be highly appreciated.

Thanking you in advance.

[allawtterb · Accepted solution]

The variable isn't allocated any space in memory because it is using a register to store the passed value.  It appears that it is using Accumulator B which can be seen in the Register window containing the hex value 71 (ASCII character 'q') in the screen shot shown. 

Edit: Fixed spelling

Message Edited by allawtterb on 2008-07-08 08:50 AM