李小冬整理
李小冬整理李小冬整理
李小冬整理
遥控
遥控遥控
遥控 NEC 格式
格式格式
格式
NEC Protocol
NEC Protocol NEC Protocol
NEC Protocol
To my knowledge the protocol I describe here was developed by NEC. I've seen very similar protocol descriptions
on the internet, and there the protocol is called Japanese Format.
I do admit that I don't know exactly who developed it. What I do know is that it is used in my late VCR produced
by Sanyo and was marketed under the name of Fisher. NEC manufactured the remote control IC.
This description was taken from the VCR's service manual. Those were the days, when service manuals were fulled
with useful information!
Features
8 bit address and 8 bit command length
Address and command are transmitted twice for reliability
Pulse distance modulation
Carrier frequency of 38kHz
Bit time of 1.12ms or 2.25ms
特点
特点特点
特点
8 位地址和 8 位命令
为提高可靠性，地址和命令都传输 2 次
脉冲间隔调制
38kHz 载波频率
每一位时间为 1.12mS 或 2.25mS
Modulation
The NEC protocol uses pulse distance encoding of the bits. Each pulse is a 560µs long 38kHz carrier burst (about 21 cycles). A logical
"1" takes 2.25ms to transmit, while a logical "0" is only 1.12ms. The recommended carrier duty-cycle is 1/4 or 1/3.
调制
调制调制
调制
采用脉冲间隔时间长短调制每一位。每一个脉冲都是 560uS 长度的 38kHz 载波脉冲，占空比
为 1/4 或 1/3（约 21 个周期）。逻辑 1：2.25mS 逻辑 0：1.12mS
