diff options
| author | heyuanjie87 <[email protected]> | 2015-09-09 10:26:42 +0800 |
|---|---|---|
| committer | heyuanjie87 <[email protected]> | 2015-09-09 10:26:42 +0800 |
| commit | 984a7ba05128992d8b89fc689f5f5e4f135e2f1b (patch) | |
| tree | 5e8474d1aa8c44af226ad5a2fd29cee21a3ba2cf /components/drivers | |
| parent | efc1b058ac553db24232aa0f49c7b573f3a498c2 (diff) | |
修改说明文档
Diffstat (limited to 'components/drivers')
| -rw-r--r-- | components/drivers/hwtimer/README_CN.md | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/components/drivers/hwtimer/README_CN.md b/components/drivers/hwtimer/README_CN.md index 8ee6f3df06..fb3b4fa60a 100644 --- a/components/drivers/hwtimer/README_CN.md +++ b/components/drivers/hwtimer/README_CN.md @@ -94,8 +94,5 @@ void timer_irq_handler(void) 假设计数器最大值0xFFFF,计数频率1Mhz,定时时间1秒又1微秒。 -由于定时器一次最多只能计时到65535us,对于1000001us的定时要求 -就需分15次完成。误差时间: 1000001 - (65535*15) = 16976us。 -这个误差太大,为了减小误差最理想的情况就是整除。实际中不可能 -所有数都被整除(1不合适),所以就只有最大限度逼近理想情况。例如 -上式中以 50000us定时20次即可将误差减小到1us(理论值,忽略指令时间) +由于定时器一次最多只能计时到65535us,对于1000001us的定时要求。 +可以50000us定时20次完成,此时将会出现计算误差1us。 |
