标签: Blue

Wifi、Blue和Zebee都是无线通信技术，它们各有不同的原理和特点。 Wifi是一种广泛使用的无线通信技术，它基于OFDM（正交频分复用）技术，可以将信号分成多个子信道，同时传输多个数据流。它具有较高的传输速率和较远的传输距离，可以在家庭、办公室和公共场所等广泛场景中应用。但是，Wifi的功耗相对较高，对于一些低功耗设备来说不够理想。 Blue是一种低功耗、低速率的无线通信技术，也称为蓝牙。它使用跳频扩频（FHSS）和时分复用（TDD）等技术，可以在较短距离内实现无线通信。Blue可以连接各种设备，如手机、电脑、耳机等，方便用户进行数据传输和控制。但是，Blue的传输速率相对较低，适合用于一些低速率的应用场景。 Zebee是一种基于Zigbee协议的无线通信技术，它使用IEEE 802.15.4标准，可以在较短距离内实现低功耗、低速率的无线通信。Zebee适合用于一些低复杂度、低功耗的物联网应用场景，如智能家居、环境监测等。它的传输速率和距离相对较低，但功耗较低，可以延长设备的续航时间。 综上所述，Wifi、Blue和Zebee都有各自的应用场景和优缺点，选择哪种技术取决于具体的需求和场景。

A week or so ago, my chum Shakeel from Blue Pearl Software and I were discussing the plethora of interfaces available to designers today and the challenges that arise when FPGA and ASIC designers implement designs with many clocks.   Out of all the challenges, perhaps the most challenging is metastability. At its most basic level, this is what happens within a register when data changes too soon before or after the active clock edge -- that is, when setup or hold times are violated.   When data is transferred between two registers with asynchronous clocks, metastability will happen. It's not a question of if it will happen; the only question is when. The thing to note is that there is no way to prevent this. All you can do is minimize its impact by placing the two clocks in different clock domains and using a synchronization technique at the crossing point, hence the term clock domain crossing.   By some strange quirk of fate, Blue Pearl has an ACE up its sleeve that solves this problem for designers in a very unique way. The Advanced Clock Environment (ACE) provides a graphical representation summarizing data paths between clocks, and it can make recommendations for grouping of clocks into domains.   With ACE, designers can identify clocks to understand how they interact with synchronizers in the design. This allows users to identify improper synchronizers or domain groupings quickly. ACE will locate errors in clock domain groupings and/or recommend appropriate domain groupings for a circuit that is synchronized.   More information can be found by clicking here . Of particular interest is that Blue Pearl has just started a campaign that lets engineers try out ACE for free .

Several days ago, my chum Shakeel from Blue Pearl Software and I were discussing the plethora of interfaces available to designers today and the challenges that arise when FPGA and ASIC designers implement designs with many clocks.   Out of all the challenges, perhaps the most challenging is metastability. At its most basic level, this is what happens within a register when data changes too soon before or after the active clock edge -- that is, when setup or hold times are violated.   When data is transferred between two registers with asynchronous clocks, metastability will happen. It's not a question of if it will happen; the only question is when. The thing to note is that there is no way to prevent this. All you can do is minimize its impact by placing the two clocks in different clock domains and using a synchronization technique at the crossing point, hence the term clock domain crossing.   By some strange quirk of fate, Blue Pearl has an ACE up its sleeve that solves this problem for designers in a very unique way. The Advanced Clock Environment (ACE) provides a graphical representation summarizing data paths between clocks, and it can make recommendations for grouping of clocks into domains.   With ACE, designers can identify clocks to understand how they interact with synchronizers in the design. This allows users to identify improper synchronizers or domain groupings quickly. ACE will locate errors in clock domain groupings and/or recommend appropriate domain groupings for a circuit that is synchronized.   More information can be found by clicking here . Of particular interest is that Blue Pearl has just started a campaign that lets engineers try out ACE for free .