xatdb - A User's Guide

Frequently Asked Questions

Please email questions here: atemu@cshcn.umd.edu.



  1. How do you decipher the console messages?


  1. How do you decipher the console messages?

    You may have noticed the console outputs messages at certain times during simulation. These messages follow a common format and can be found in the chip debug and event tabs as well. Here's an example of the messages encountered when starting the blink application:

    000 0 opcode A0x000000: JMP 0x00008c
    ...Finished Loading!
    000 370 event led Red on
    000 393 event led Yellow on
    000 416 event led Green on
    000 900 event led Red off
    000 923 event led Yellow off
    000 946 event led Green off

    The first three digits in each line represent the chip number; 000 refers to chip 0, 001 refers to chip 1, and so on. The next number is the processor's cycle count. This number grows very quickly during execution. To the right of the cycle count is the message type. This can be an opcode, event, or debug. "Opcode" tells you the rest of the message is the machine instruction represented in hexadecimal, followed by the assembly function name. An "event" tells you what device triggered the event and what message the device sent. "Debug" currently informs you when breakpoints and watchpoints are set, hit, and cleared. After allowing your program to run for a while and then pressing stop, you may get a line similar to:

    000 459087353 opcode A0x000b58: SLEEP

    The 000 would tell you this message pertains to chip 0 and the 45908753 would tell you the cycle number chip 0 stopped on. It then tells you specifically what opcode was being executed at that cycle: SLEEP, located at hexadecimal address A0x000b58.