The difference between the general IO and peripheral functions of the single chip microcomputer

I feel like what you said is weird.,What the general I-O port of the single-chip microcomputer is talking about is the general I.O.,Can output high and low levels,Peripheral functions? General external devices, such as cameras or printers, they specifically implement certain functions (taking pictures or printing documents), single-chip microcomputer to control these external devices, generally speaking, the IO port of the single-chip microcomputer is connected to the pins of these peripherals, and the control of external devices is realized through the IO pins, so that they can complete the functions we require.

General I/O, also known as GPIO, means that the high and low state of this IO can be set arbitrarily, and the peripheral function means that this IO is designated as a specific function, for example.

SPI, I2C, and IOs designated as peripheral functions cannot be arbitrarily controlled, but must be controlled by SPI, I2C, and other controllers.

The basic IO is the MCU that comes with it, and the strobe IO is extended through the IO chip, which should be what you mean, right?

When the IO port of the microcontroller itself is not enough, it needs to be expanded.

The basic ios and the extended strobe ios are different in the read and write instructions at the time of programming.

When configured for this function, an IO port is connected to a bit of an output register, and also to a bit of an input register.

Through GPIO, the TTL level of 1 or 0 can be directly output, and as for the influence of the external circuit, it also depends on the pull-up, pull-down, and open-drain auxiliary characteristics of the port.

With GPIO, TTL levels of 1 or 0 can be read directly, and the reading results are also affected by the coupling of the pull-up, pull-down, and open-drain auxiliary characteristics of the port with the external circuitry.

For example, for open-drain inputs, the external circuit must have a pull-up or pull-down circuit to provide a clear level in order to read a clear result;

On the contrary, if the external circuit is also open and leakage, it will become a suspended line and receive the electromagnetic induction of the mains, and the reading result will become high and low.

The peripherals in "Peripherals IO" refer to on-chip and external peripherals (timers, ADCs, usarts). When the port is configured as peripheral IO, the original GPIO connection will be disconnected, and the input or output of a peripherals will be connected instead. Some chips have a port redirection function, which also switches some ports to other explicit pins to facilitate routing.

To understand the specific definition and characteristics of the port, you should carefully read the data sheet or user instructions provided by the chip manufacturer.

For the sake of the commonality of programming and logical expression, the identification of the IO port is usually represented by the function name (p number). For example, the C51 single-plate machine refers to the 0th and 1st bits of the P0 port, and the P0 port refers to a group of 8 ports. The chip of the C51 core usually has a total of 5 ports of P0 and P4, which may be reduced depending on the specifications and models.

STM32 uses PA, PB, PC, PD, PE, and PF to represent 6 groups of ports (groups), and the PA port has a total of 16 channels (bits) from PA0 to PA15. As for how the specific io port corresponds to the pins that are drawn out, the definition of chips of the same model and different packages (the letters behind the model are different) are different. Check the data sheet for the full model in use.

The Io interface means the input interface and the output interface, for a computer must have at least one input interface and one output interface, otherwise it is meaningless.

port"It is a paraphrase of English port, which can be regarded as the outlet for communication between the equipment and the outside world.

Ports can be divided into virtual ports and physical ports, where virtual ports refer to ports inside a computer or a switch router and are invisible.

It can be said that a "port" is a kind of I.O. interface.

The connection and data exchange between the CPU and external devices and memory needs to be realized through interface devices, the former is called the IO interface, and the latter is called the memory interface. The memory usually works under the synchronous control of the CPU, and the interface circuit is relatively simple; There are many types of IO devices, and their corresponding interface circuits are also different, so it is customary to refer to the interface only when it comes to the IO interface.

If we follow the concept in the computer system, the general methods of the IO interface include port address mode, interrupt mode, DMA mode, and so on. If you mean the port address of the device, that's the concept.

If you mean all interface specifications by peripheral ports, I o-interfaces and peripheral ports are the same thing.

I don't really understand your definition, what is the basic iO? And it's not clear what the single-chip microcomputer model you're talking about.

But I guess there is a slight difference in the driving ability or the internal circuit of the chip.

The basic IO is the MCU that comes with it, and the strobe IO is extended through the IO chip, which should be what you mean, right?

When the IO port of the microcontroller itself is not enough, it needs to be expanded.

The basic ios and the extended strobe ios are different in the read and write instructions at the time of programming.

It's up to you to use.

All right. It's all the same when used as IO.

Microcomputer: The whole of the microprocessor (CPU), memory, and IO interface circuits that are organically connected together by the bus is called a microcomputer.

Microcontroller: The microprocessor (CPU), memory, IO interface circuit and corresponding real-time control devices are integrated on a chip, which is called a single-chip microcomputer, referred to as single-chip microcomputer.

The main differences between the two:

1) The CPU of general-purpose microcomputer is mainly oriented to data processing, and its development mainly revolves around the further improvement of data processing function, computing speed and accuracy. The single-chip microcomputer is mainly oriented to control, and the data type and data processing in the control are relatively simple, so the data processing function of the single-chip microcomputer is relatively weaker than that of the general-purpose microcomputer, and the calculation speed and accuracy are relatively lower.

2) The memory organization structure in the general-purpose microcomputer is mainly aimed at increasing the storage capacity and the speed of CPU access to data. The organizational structure of the memory in the microcontroller is relatively simple, the memory chip is directly attached to the bus of the microcontroller, and the CPU addresses the memory unit according to the direct physical address of the memory read/write, and the addressing space of the memory is generally 64 KB.

3) The IO interface in the general computer mainly considers standard peripherals (such as CRT, standard keyboard, mouse, printer, hard disk, CD-ROM, etc.). The IO interface of the microcontroller is actually the physical interface that is provided to the user to connect with the peripherals. Users need to design specific interface circuits for the connection of peripherals, and they need to have proficient interface circuit design technology.

It's hard to describe the difference in a few words.

To put it simply, a single-chip microcomputer is similar to a mini-type general-purpose microcomputer.

Choose according to your actual needs.

For example, when the external circuit is LED or button, it can be configured as a universal interface; If the external circuit structure is SPI, IIC, UART, etc., it must be configured as a peripheral interface.

Reply content: Yes: Ah Shui about what is the difference between the I O image area and the peripheral I 0 storage area, the main difference is that one is recorded in the CPU after PLC scanning.

ROM area, the other is a memory area on an external I/O module that can be directly accessed by the PLC.

Reply to the content: Then PI and I have nothing to do with peripheral hardware, for example, for a certain point on an IO module, is it possible to use I**I can use pi**