Generally, if CPU has a ICE interface that will be the best way to debug. The second choice is to use UART for dumping some message. The 3rd choice uses so called 80 port to latch data bus of one debug port. The last way is GPIO.
Designer can modify the 8225 (use mode 0 only)or directly use it if don't care gate count, hook up GPIO in low speed bus(for example, ISA bus) in your chip.
Use gpio as debug tool, designer can add an 8 segment LED display to let software easilier debugging. It can show differnet number on it to identify what stage the software has excuted.
发表时间:2003年8月27日15:40:26