Hardware basics/zh-hans
In this section we will describe some basis of hardware involved in Nano.
Contents |
Block Diagram
Power Supply
Oscillators
Boot
Jz4720 support 3 different boot sources. The boot sequence is controlled by boot_sel pin values [1:0]. The configuration of BOOT_SEL1 and BOOT_SEL1 [1:0] is showed as below:
| BOOT_SEL0 | BOOT_SEL1 | action |
|---|---|---|
| 0 | 0 | Boot from external ROM at CS4 |
| 0 | 1 | Boot from USB device |
| 1 | 0 | Boot from 512 page size NAND flash at CS1 |
| 1 | 1 | Boot from 2048 page size NAND flash at CS1 |
Memories
Is necesary, for the operation of the Nanonote Board store many sections of executable programs in volatile and non-volatile memories. The volatile memories are used like Random Acces Memories (RAM) because to its low acces time and unlimit number of Read/Write cycles. Moreover, the Non-volatile memories (NAND, SD) stores for longs periods of time the required information to operation of the Embedded System.
Audio
LCD
USB
Universal Serial Bus (USB) is a way of setting up communication between a computer and peripheral devices. USB is intended to replace many varieties of serial and parallel ports. USB can connect computer peripherals such as mice, keyboards, PDAs, gamepads and joysticks, scanners, digital cameras, printers, personal media players, flash drives, and external hard drives. For many of those devices, USB has become the standard connection method.
A USB system has an asymmetric design, consisting of a host, a multitude of downstream USB ports, and multiple peripheral devices connected in a tiered-star topology. Additional USB hubs may be included in the tiers, allowing branching into a tree structure with up to five tier levels. A USB host may have multiple host controllers and each host controller may provide one or more USB ports. Up to 127 devices, including the hub devices, may be connected to a single host controller.
