| 摘要 |
PROBLEM TO BE SOLVED: To prevent the bus of a system from being occupied and a system from being frozen even when a wait signal outputted by a PC card is continuously asserted. SOLUTION: When the wait signal outputted by the PC card is asserted, a timer part 201 is activated and when it is detected the wait signal is asserted continuously longer than certain fixed time, the timer part 201 asserts a wait mask signal. When the wait mask signal is asserted, a mask part 202 negates the wait signal to a CPU by masking the wait signal from the PC card even when the wait signal from the PC card is asserted. Besides, when the wait mask signal is asserted by the timer part 201, an interruption control block/card status register 210 asserts an interrupt signal to the CPU. |
