AM335x硬件开发使用指南(三)

Functional Block Diagram

这里写图片描述

三、Parallel

由于本人认为翻译为并行功能特别的土,所以就直接用上Parallel这个单词了

下面进入主题

前言
AMR335X包含多媒体卡(MMC),安全数字(SD)和安全数字I / O(SDIO)3个高速接口模块(MMCHS)。AMR335X为MMC,SD存储卡或SDIO卡提供接口。

而且对于这3个接口(MMC/SD/SDIO)来说都是使用以下的几个引脚:

• MMC_CMD This pin is used for two-way communication between the connected card and the MMC/SD/SDIO controller. The MMC/SD/SDIO controller transmits commands to the card and the memory card drives responses to the commands on this pin;

• MMC_DAT7-0 Depending on which type of card you are using, you may need to connect 1, 4, or 8 data lines. The number of DAT pins (the data bus width) is set by the Data Transfer Width (DTW) bit in the MMC control register (SD_HCTL). For more information, see the registers section of this document;

• MMC_CLK This pin provides the clock to the memory card from the MMC/SD controller;

• MMC_POW Used for MMC/SD card’s cards on/off power supply control. When high, denotes power-on condition;

• MMC_SDCD This input pin serves as the MMC/SD/SDIO carrier detect. This signal is received from a mechanical switch on the slot;

• MMC_SDWP This input pin is used for the SD/SDIO card’s write protect. This signal is received from a mechanical protect switch on the slot (system dependant). Applicable only for SD and SDIO cards that have a mechanical sliding tablet on the side of the card。
这里写图片描述

1、Multimedia Card(MMC)

用AMR335X设计多媒体基本准从如下
这里写图片描述

用到CLK时钟脚/CMD命令脚和DATA[0:7]八位数据线


2、SD

这里写图片描述

SD卡的通信支持两种方式一种是SD总线模式、一种是SPI模式(对几个使用的定义不一样)

而实际使用中,我们是可能插SD卡使用,也有可能不插SD卡使用,因此不插SD卡使用时,这几个信号交就存在浮空状态了,因此硬件设计中会通过给CMD和DATE脚上拉个10K的电阻来处理浮空问题。

这里写图片描述

3、Secure Digital I/O (SDIO)
AMR335X拥有3路的SDIO
这里写图片描述


4、GPIO
AMR335X一共有4组通用输入输出
每组输入输出有32个引脚。
你可要用这些GPIO来开发很多东西,包括了键盘、或则PWB捕获等等。

其中第一组GPIO0和其他三组有点小区别,
GPIO0 is in the Wakeup domain and may
be used to wakeup the device via external sources. GPIO[1:3] are located in the peripheral domain.
这里写图片描述

转至:
https://mp.weixin.qq.com/s/LHOcr66ktBisaYdORG-2cQ

欢迎关注本人公众号:
这里写图片描述

AM335x硬件开发使用指南(一)
https://blog.csdn.net/weixin_42124889/article/details/80514842

AMR335x硬件开发使用指南(二)
https://mp.weixin.qq.com/s/krjhaz7LvXxiT2a9pvnAFw

聊聊无线充电——华为Mate RS保时捷版无线充电器详解(上篇)
https://blog.csdn.net/weixin_42124889/article/details/80290757

聊聊无线充电——华为Mate RS保时捷版无线充电器详解(下篇)
https://mp.weixin.qq.com/s/9o8-7YANXCiydjQ8u-EDsg

手机快充技术——快充技术&硬件详解
https://blog.csdn.net/weixin_42124889/article/details/80255434

一文知晓高通晓龙845
https://mp.weixin.qq.com/s?__biz=MzU2NjYwMzQ1Ng==&mid=2247483678&idx=1&sn=c396ca9582a7f5124e0b00cb94d6a482&chksm=fca8bab1cbdf33a79189346c9ed964bca08f446427f67a509b3577bec2fd533fe6aeb39d5eaf#rd

A12 chip即将来临,是IPhone XI?
https://mp.weixin.qq.com/s/j3IJdhY1CKS7aW120zgs8Q

猜你喜欢

转载自blog.csdn.net/weixin_42124889/article/details/80571506