8253可编程定时/计数器为()计数器,当作为定时器使用时,其定时基准由()确定。
A. 二进制计数
BCD
C. 二进制或BCD
D. 输入CLK频率
E. 计数器计数值
F. 定时时间常数(计数初值)
查看答案
若给8253的计数器预置的初值=400,则当计数器计到数值为0时,时间= ____ms,设8253的计数脉冲频率为0.5MHz。
成本分析模式是通过分析持有现金的相关成本，寻求持有成本最低的现金持有模式。（）
A. 对
B. 错
When did the Californian wine workers begin the strike ?
A. This week
B. Last week
C. Six weeks ago
D. Seven weeks ago
Why did the workers go on strike?
A. The winery owners propose to cut their wages.
B. The winery owners propose to cut their wages and benefits.
C. The winery owners propose to fire them.
D. The winery owners propose to use non-union workers.
微信支付 
支付宝支付