Shenzhen Chuanglixin Electronics Co., Ltd.

 

 

What is HMI

 

 

HMI is the abbreviation of Human Machine Interface, "Human Machine Interface", also called Human Machine Interface. The man-machine interface is the system and

 

 

The medium of interaction and information exchange between users, which realizes the conversion between the internal form of information and the form acceptable to humans. Where

 

 

There are man-machine interfaces in the fields that participate in man-machine information exchange.

 

 

What is serial HMI

 

 

Serial HMI means that after the device encapsulates the underlying functions of HMI, it communicates with the user MCU through the serial port (USART 232).

 

 

For example, MCU can send instructions through USART at any time to notify the device to switch a certain page or change the properties of a certain component. Assume

 

 

The device can also notify the user through the USART at any time that the MCU operator has touched a certain component on the page or the device is currently entering

 

 

A certain page.

 

 

What is the difference between a serial HMI and a normal display, and how should I select it.

 

 

For product developers, there are only three types of interfaces that can be selected at the initial stage of product development: RGB interface, MCU bus

 

 

Interface, serial port HMI.

 

 

RGB interface:

 

 

The RGB interface must be used on ARM chips with RGB drivers. General ARM9 chips have a few support RGB, and most chips above ARM9 support RGB. However, the driver of this type of interface is the most complicated and requires the highest hardware. The detailed driver details will not be discussed here.

 

 

MCU bus interface:

 

 

The MCU bus interface driver is simpler than RGB, and there is basically no hardware requirement. As long as it is an MCU, it can drive

 

 

move. However, the display speed is a big bottleneck. Most users’ MCUs are in ARM7 such as 51 core or stm32.

 

 

nuclear. The screen speed of the driver bus interface is not ideal. Of course, the ARM7 core also has ultra-high speed. But the chip cost is also relatively

 

 

High, fewer people use it. In addition to the speed bottleneck, the display driver of the interface is also a headache for most users. total

 

 

The linear interface screen only provides dot matrix operation. Any display content such as pictures, characters, etc., are displayed on the screen through modulo data.

 

 

Position the dot matrix one by one. On this basis, we will realize the logic of the man-machine interface. Heavy workload. usually,

 

 

For example, to make an English keyboard, the developer may have to spend several weeks to make it. And it's quite similar in later modification

 

 

Strenuous.

 

 

Serial HMI

 

 

For developers, serial HMI is the simplest display solution. First of all, he has no impact on the user’s hardware like the MCU bus screen.

 

 

There are any requirements, secondly. It has no speed bottleneck, because the interface display is implemented by the device itself, and the user MCU just sends

 

 

1

 

 

Introduction to Serial HMI

 

 

Shenzhen Chuanglixin Electronics Co., Ltd. http://www.chinalcdclx.com

 

 

Address: Fenghuang No.1 Industrial Zone, Fuyong, Baoan District, Shenzhen. Tel: 0755-27337559, 27345677 Fax: 0755-81461216

 

 

Shenzhen Chuanglixin Electronics Co., Ltd.

 

 

Sending instructions does not require the underlying driver. Third, for the layout of the displayed man-machine interface and most of the logic (such as interface background,

 

 

Button effects, text display, etc.). All do not need the user’s MCU to participate, use the upper software provided by the device, on the computer

 

 

It's done in a few clicks. After making the resource file, download it to the screen and it will run automatically, and the rest is USART interaction

 

 

(The user MCU can modify the content on the interface through simple object operation instructions during operation).

 

Although serial HMI is the simplest display solution, does that mean it is the most expensive display solution?

 

In terms of hardware production cost alone, serial HMI is indeed a little bit more expensive. But here we have to consider two

 

Question, first: Is it worth the extra cost to use this advanced feature? Second: In addition to production costs, R&D costs

 

And later maintenance costs have you taken into consideration? Have you taken into consideration the losses caused by the delay of the launch of new products due to the long R&D cycle? Correct

 

Because of these two issues. We believe that there is no absolute answer here. Different people have different opinions. Different people will come up with different answers.

 

Can you generalize in simple language what is serial HMI, so that I can quickly understand its characteristics.

 

Regardless of the RGB interface screen or the MCU bus interface screen, the developer wants to display any content (note that it is any content, not

 

Regardless of pictures, text, or coloring) In the final analysis, the user's MCU is all drawing the bottom layer of the points on the screen. Any figure

 

The shape is the state of the user at each point on the control screen. Intuitively, the user MCU controls the dot matrix on the screen.

 

The serial HMI overturned this application. The control of the dot matrix on the screen is now handed over to the main control chip inside the device. For users

 

Is no longer a dot matrix. what is that? you guessed right! It is a control. What is a control? It is a function encapsulated by serial HMI

 

Module. Where did the controls come from? Created in the supporting upper software, for example, to display a paragraph of text in the upper left corner, just in

 

Create a text control in the upper left corner, to display a button in the lower right corner, create a button control in the lower right corner, and so on. Introduce

 

After the control is operated, the user MCU does not need to control the display state of which points need to be controlled to display a content. Even the coordinates do not need to be operated in the user MCU. From now on, users only need to pay attention to the properties of these controls on the screen. In operation, the user MCU can change the content displayed on the screen by changing the attributes of the control through the serial port command. In addition, the controls also have touch event functions. That is, it can actively notify the user after being touched, or it can automatically execute some instructions.