The ITT IR protocol is a very old one. It differs from other protocols in that it does not use a modulated carrier frequency to send the IR messages. A single command is transmitted by a total of 14 pulses with a width of 10µs each. The command is encoded by varying the distance between the pulses.
This protocol used to be very reliable and consumes very little power ensuring long battery life. One big disadvantage of this old protocol is that it sometimes triggers false commands, for instance when you put a laptop computer with an active IRDA port close to the IR receiver.

翻译:
   ITT 编码协议是一个非常老的编码协议。这个协议区别于其他协议之处是它没有用调制频率来发送红外信号。它以每个脉冲10us开头的14个脉冲组成一个基本编码。通过改变每个脉冲之间的间隔时间来改变编码指令。
   这个编码协议经过使用证实非常可靠，它消耗非常小的功率，确保了电池的长时间使用。它的一个最大缺点是有时它会触发错误的指令，譬如，当你把一个具有IRDA接口的笔记本电脑放在红外接收器边上时就会出现误触发。

Many consumer electronics brands used this protocol in Europe. Among them were: ITT, Greatz, Schaub-Lorenz, Finlux, Luxor, Salora, Oceanic and later also Nokia, to name but a few.

翻译：
    在欧洲有很多消费电器品牌都使用这个协议。其中有：ITT, Greatz, Schaub-Lorenz, Finlux, Luxor, Salora, Oceanic，后来有Nokia。

• Only 14 very short IR pulses per message 每个基本信息只有14个短红外脉冲
• Pulse distance encoding 脉宽调制方式
• Long battery life 长电池寿命
• 4 bit address, 6 bit command length 4位地址码，6位功能码
• Self calibrating timing, allowing only simple RC oscillator in the transmitter 自我校验时间长度，允许在遥控器内使用简单的RC振荡作为时钟源
• Fast communication, a message takes from 1.7ms to 2.7ms to transmit 快速通讯，发送一个基本信息只花费1.7ms---2.7ms时间
• Manufacturer Intermetall, now Micronas 生产厂家：Intermetall和Micronas

An IR message is transmitted by sending 14 pulses. Each pulse is 10µs long. Three different time intervals between the pulses are used to get the message across: 100µs for a logic 0, 200µs for a logic 1 and 300µs for the lead-in and lead-out.

翻译：
   一个IR信息发送14位脉冲。每个脉冲10us。三种不同的时间间隔用于表示逻辑0（100us），逻辑1（200us）和引导和结束码（300us）。

The preliminary pulse is used by the receiver to set the gain of the amplifier. Then follows a lead-in interval of 300µs, after which the starting pulse is given. The first bit sent is always logic 0, which has an interval duration of 100µs. This start bit can be used to calibrate the timing of the receiver. After the start bit follow 4 bits (MSB first) that represent the address of the message. After that a total of 6 bits (MSB first) for the command are transmitted. A trailing pulse should follow this command word. Finally another 300µs interval follows before the very last pulse is given, functioning as a lead-out.

翻译：
    第一个脉冲对接收器用于设定放大器的增益。接着300us的时间间隔，然后是引导脉冲。引导脉冲总是逻辑0，100us间隔。这位用于校验接收器的定时。接着是4位地址码（MSB，高位先发）和6位功能码（MSB），紧跟一个拖尾脉冲代表功能码的结束，最后是结束脉冲。

There are a few things the receiving software can check to verify the validity of the received message. The lead-out interval should be 3 times longer than the start bit time, which has a duration of 100µs. Bit times should not be off by more than ±20% of the start bit length for logic 0s, or 2x the start bit length for logic 1s.
Don't keep waiting for pulses after 360µs after the last received pulse. It's very likely that the transmission is interrupted or no transmission took place at all if you have to wait longer than that.
The preliminary pulse serves only AGC purposes and may be ignored by the receiving software. Decoding of the message should start at the Start pulse.

翻译：
        软件收到信息后需要进行校验信息的有效性。结束码必须是引导码的3倍宽度，逻辑位宽度的有效范围是 ±20%。收到最后的脉冲后超过360us无需等待。第一个脉冲可以被忽略，解码软件可以从引导脉冲开始处理。

A control message is divided into two groups, an address of 4 bits and a command of 6 bits. By convention the addresses range from 1 to 16, and commands range from 1 to 64. Before the address and command are sent, 1 is subtracted from both values to get them in the range 0 to 15 and 0 to 63.

翻译：
    一个控制信息分为2部分，4位地址码和6位功能码。地址码从1-16，功能码从1-64。在地址码和功能码发送之前，地址码和功能码都减去1，结果是0-15和0-63。（目的是为了二进制数表示的方便）。

Addresses are used in pairs. A pair of addresses is a value of 1 to 8 (0 to 7 actually), and its inverted counter part 16 to 9 (15 to 8 actually).
The lower value address is transmitted the first time a key is pressed. The address value of all subsequent messages will be the inverted value of this first address until the key is released. This enables the receiver to interpret repeat codes properly. Messages are repeated every 130ms as long as the key remains pressed.

翻译：
    地址码成对使用，是1-8（0-7）和它的反码16-9（15-8）。当键按下，低位先发，后续的信息的地址码是第一个信息的反码，目的是为了让接收器识别键松开前的重复码。信息每130ms重复一次，重复到按键松开为止。
（以上图片为本站添加）

Intermetall has developed a few transmitter ICs for use in handsets. Later microcontrollers were used to facilitate the combination of TV, VCR and SAT remote control in one handset.

翻译：
   Intermetall已经开发了一些发射器IC。后来的单片机用来把TV，VCR，和SAT的遥控器组合在一只遥控器内，使得遥控家电更方便容易了。

The SAA1250 was the first IR controller IC to be released. It can be set to generate 3 different address pairs. A fourth option is transmitting any of the 16 addresses. That option is rarely used, for it requires a manual setup procedure every time the power is lost.

翻译：
    SAA1250是第一个投放市场的红外遥控IC。它可产生3种不同的地址对。第四种选择是发送16个地址中的一个。这种情况很少用到，因为换电池时需要手动设置。

The second generation of IR controller ICs are the IRT1250 and IRT1260. These chips are identical in operation and differ only in the operating voltage. The IRT1250 is intended for 9V operation, whilst the IRT1260 is designed for 3V.
The footprint of the IRT12x0 is the same as that of the SAA1250. The devices differ in addressing capability and current drive capacity for the output stage.

翻译：
     第二代红外遥控IC是IRT1250和IRT1260。这些IC的操作是相同的，区别是不同的工作电压。IRT1250用于9V工作电压，IRT1260用于3V工作电压。这些IC的引脚和SAA1250完全相同。这些IC的不同在于地址的适用能力和输出驱动电流的大小。

Two address pins are available to set the address pair used.

     两个地址引脚被用于设置地址对。

Addresses 1 and 16 are always used to control TV sets. Other address pairs are not always uniquely linked to a particular equipment family.

    地址1和16总是用于控制电视机。其他地址对不和电器有什么匹配关系。

The ITT protocol makes no use of a modulated carrier, so the previously mentioned IR receivers won't work for this protocol. Intermetall has created the TBA2800 for use with this protocol. It is a highly sensitive IR detection circuit and should be shielded completely inside a metal box that is connected to ground, leaving only a small hole just in front of the IR diode.

翻译：
    ITT协议没有载波，所以以前提到的IR接收器不能用于这个协议。Intermetall 制造了TBA2800用于这个协议的接收。它具有很高灵敏度的IR检测电路和封装在一个金属壳内（接地），只在IR接收二极管前端留一个小孔。

There is actually not much more to be told about this IC. Just connect it as shown in the diagram and it should work. You can chose between a normal high going output, and an inverted low going output. It depends on the rest of your circuitry which one you should use.
In case of excessive interference you could reduce the sensitivity a little by grounding pin 6 via a 10kΩ resistor.

翻译：
    实际中，资料中提到这个IC的内容很少。按照以上电路接起来就可以工作。你可以选择高电平输出，也可以选择低电平输出，取决于你设计的电路的需求。为了避免干扰，你可以在6脚接一个接地电阻10K欧姆来调节增益。

Some of the 64 possible commands are predefined. But unfortunately the definition of the commands is not as clear as with RC-5. You can find most of the pre-defined commands for TV purposes in the following table. TV commands use the address pair 1 and 16.

翻译：
    64个功能码中的一部分预先定义了特定的功能。但是，RC-5并没有这么做。你可以找到大多数针对电视机的预定义功能码。电视机采用1和16的地址对。

后记：
1，本编码格式是典型的无载波编码格式。
2，文中翻译内容仅供参考，请勿咬文爵字。有不同意见者可发表评论。
3，文中内容是以欧洲市场为背景的，请勿套用到中国市场。