CN203644032U - Serial port extender circuit - Google Patents
Serial port extender circuit Download PDFInfo
- Publication number
- CN203644032U CN203644032U CN201320830891.4U CN201320830891U CN203644032U CN 203644032 U CN203644032 U CN 203644032U CN 201320830891 U CN201320830891 U CN 201320830891U CN 203644032 U CN203644032 U CN 203644032U
- Authority
- CN
- China
- Prior art keywords
- chip
- pin
- capacitor
- chip microcomputer
- serial
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Abstract
The utility model provides a serial port extender circuit which comprises a single chip microcomputer, a serial port extending chip, a printed circuit board and an inserting pin circuit. The single chip microcomputer and the serial port extending chip are connected through the printed circuit board. The serial port extending chip is provided with a mother serial port COM and seven child serial ports from COM0 to COM6. The inserting pin circuit is controlled from the outside to be switched between a first working mode and a second working mode. Under the first working mode, the inserting pin circuit is connected with the single chip microcomputer and an upper computer, so that direct communication is achieved, under the second working mode, the inserting pin circuit is connected with the upper computer, the child serial port COM0 of the serial port extending chip, the single chip microcomputer and the mother serial port COM of the serial port extending chip, the child serial ports COM1-COM6 of the serial port extending chip are connected with six lower computers respectively, and data collected by the lower computer are transmitted to the single chip microcomputer through the child serial ports COM1-COM6 and are transmitted to the upper computer though the child serial port COM0.
Description
Technical field
The utility model relates to serial port communication technology field, in particular to a kind of serial extended unit circuit, is applicable to solve the communication issue between host computer and multiple serial equipment.
Background technology
Conventionally the method single serial ports expansion of computing machine being adopted for many serial ports is to increase switching device, roughly there is following several mode: directly serial ports is expanded (software simulation), expansion card is installed on PCI slot, is utilized USB switching serial ports and utilize serial port extended chip, but extension principle is not quite similar.
Software simulation serial port is mainly that the I/O mouth simulation Asynchronous Serial Interface sequential by single-chip microcomputer realizes, and this mode expands that the serial ports forming is not only high to the performance requirement of single-chip microcomputer, and the scope of application is little, general only for the software simulation of 1～2 serial ports.Pci bus extended method is to expand by insert multiple serial port boards on the pci expansion slot of computing machine, owing to having adopted timesharing control, and needs manual gating serial ports, when multiple serial ports may occur loss of data phenomenon in the time that host computer sends data simultaneously.It is current more conventional serial ports expansion scheme that USB turns serial ports, but in the time that needs are expanded multiple serial ports, first needs to adopt USB-HUB to expand USB interface, and then extended serial port, and not only operation inconvenience, has also increased expansion cost simultaneously.
Utility model content
The defect or the deficiency that exist for prior art, the purpose of this utility model is to provide a kind of compact conformation, is easy to the serial extended unit circuit of extended operation.
For reaching above-mentioned purpose, the technical scheme that the utility model adopts is as follows:
A kind of serial extended unit circuit, comprise a single-chip microcomputer, a serial port extended chip, a printed circuit board (PCB) and a contact pin circuit, between described single-chip microcomputer and serial port extended chip, be connected by described printed circuit board (PCB), described serial port extended chip is provided with 1 female serial ports COM and 7 sub-serial ports COM0～COM6, and described contact pin circuit controllably switches from outside between the first mode of operation and the second mode of operation:
Under the first mode of operation, described contact pin circuit connects described single-chip microcomputer and a host computer makes its direct communication;
Under the second mode of operation, described contact pin circuit connects host computer and the substring mouth COM0 of serial port extended chip and female serial ports COM of single-chip microcomputer and serial port extended chip;
The substring mouth COM1～COM6 of described serial port extended chip is connected with 6 slave computers respectively, and the data of slave computer collection transfer to single-chip microcomputer by described substring mouth COM1～COM6, and are forwarded to host computer by substring mouth COM0.
In further embodiment, the AT89C2051 single-chip microcomputer that described single-chip microcomputer is atmel corp.
Further in embodiment, the RESET pin of described AT89C2051 single-chip microcomputer is connected with reset circuit, this reset circuit is made up of power supply VCC, capacitor C 1, button S1 and resistance R 1, wherein power supply VCC is connected with the RESET pin of button S1 and chip AT89C2051 by capacitor C 1, again by resistance R 1 ground connection, the capacity of capacitor C 1 is 10uf, and the resistance of resistance R 1 is 10K Ω.
Further in embodiment, described AT89C2051 single-chip microcomputer is connected with clock driver circuit, this clock driver circuit is made up of capacitor C 2, capacitor C 3 and quartz crystal, wherein, one end ground connection after capacitor C 2 is in parallel with capacitor C 3, the other end is connected with XTAL2 pin, the XTAL1 pin of AT89C2051 single-chip microcomputer respectively, and quartz crystal is connected between capacitor C 2 and capacitor C 3, the capacity of capacitor C 2 and capacitor C 3 is 22uf, and the oscillation frequency of quartz crystal is 11.0592MHz.
Further in embodiment, described serial port extended chip adopts the SP3739 chip of Chengdu Shipu Technology Co., Ltd., the two-way I/O mouth of described AT89C2051 single-chip microcomputer is connected with address delivery outlet with the input port, address of this SP3739 chip, wherein: P1.2～P1.4 pin of AT89C2051 single-chip microcomputer is connected with address input end mouth ADRI0～ADRI2 pin of SP3739 chip as output port, P1.5～P1.7 pin of AT89C2051 single-chip microcomputer is connected with address output end mouth ADRO0～ADRO2 pin of SP3739 chip as input port.
Further in embodiment, the P3.1 pin of described AT89C2051 single-chip microcomputer is connected with the RX7 pin of SP3739 chip, this RX7 pin is that the input port of female serial ports COM of SP3739 chip receives the director data from AT89C2051 single-chip microcomputer, the P3.0 pin of described AT89C2051 single-chip microcomputer is connected with the TX7 pin of SP3739 chip, and this TX7 pin is that the output port of female serial ports COM of SP3739 chip sends data to AT89C2051 single-chip microcomputer.
Further in embodiment, described SP3739 chip is connected with clock driver circuit, this clock driver circuit is made up of capacitor C 4, capacitor C 5 and quartz crystal, wherein, one end ground connection after capacitor C 4 is in parallel with capacitor C 5, the other end is connected with OSCO pin, the OSCI pin of SP3739 chip respectively, and quartz crystal is connected between capacitor C 4 and capacitor C 5, the capacity of capacitor C 4 and capacitor C 5 is 22uf, and the oscillation frequency of quartz crystal is 16.0MHz.
Further, in embodiment, the VCC1 pin of SP3739 chip is clock power, is connected with a power supply VCC; The GND1 of SP3739 chip is clock ground, passes through capacitor C 6, C7 ground connection with power supply VCC; The VCC2 pin of SP3739 chip is logic power, and VCC is connected with power supply; The GND2 pin of SP3739 chip is logically, passes through capacitor C 8, C9 ground connection with power supply VCC; TX0, the TX1 of SP3739 chip, TX2, TX3, TX4, TX5, TX6 are data receiver port, and wherein TX0 is for receiving the data from host computer, and TX1, TX2, TX3, TX4, TX5, TX6 are for receiving the data from slave computer; RX0, the RX1 of SP3739 chip, RX2, RX3, RX4, TX5, RX6 are data sending terminal mouth, and wherein RX0 is for sending data to host computer, and RX1, RX2, RX3, RX4, TX5, RX6 are for sending data to slave computer.
From above the technical solution of the utility model, the beneficial effects of the utility model are: 1) single-chip microcomputer can be processed the data that collect, and have alleviated the programming pressure of host computer; 2) all substring mouths can receive simultaneously, send data, and each substring mouth can receive or send FIFO independently; 3) the shared original serial ports of host computer of all substring mouths interrupts realizing the sending and receiving function of data, and can not take external interrupt and the parallel data bus line of host computer.
Brief description of the drawings
Fig. 1 is the circuit connection diagram of the utility model one embodiment serial extended unit circuit.
Fig. 2 is the connection diagram of single-chip microcomputer and serial port extended chip in Fig. 1 embodiment.
Embodiment
In order more to understand technology contents of the present utility model, especially exemplified by specific embodiment and coordinate appended graphic being described as follows.
Fig. 1 is the circuit connection diagram of the utility model one embodiment serial extended unit circuit, wherein, a kind of serial extended unit circuit, comprise a single-chip microcomputer 1, a serial port extended chip 2, a contact pin circuit 3 and a printed circuit board (PCB) (not shown), between single-chip microcomputer 1 and serial port extended chip 2, be connected by printed circuit board (PCB), serial port extended chip 2 is provided with 1 female serial ports COM and 7 sub-serial ports COM0～COM6, and contact pin circuit 3 controllably switches from outside between the first mode of operation and the second mode of operation:
Under the first mode of operation, download debugging mode, contact pin circuit 3 connects single-chip microcomputer 1 and a host computer 4 makes its direct communication (the 1. number line conduction in Fig. 1), program can be downloaded to single-chip microcomputer 1 from host computer 4 like this;
Under the second mode of operation, i.e. operational mode, contact pin circuit 3 connects the 2. number line conduction in female serial ports COM(Fig. 1 of the substring mouth COM0 of host computer 4 and serial port extended chip 2 and single-chip microcomputer 1 and serial port extended chip 2);
The substring mouth COM1～COM6 of aforementioned serial port extended chip 2 is connected with 6 slave computers (slave computer 1-6) respectively, the data that slave computer (slave computer 1-6) gathers transfer to single-chip microcomputer 1 by substring mouth COM1～COM6, and are forwarded to host computer 4 by substring mouth COM0.The address wire of serial port extended chip 2 is connected with the address wire of single-chip microcomputer 1 by printed circuit board.
In the present embodiment, the AT89C2051 single-chip microcomputer that single-chip microcomputer 1 is atmel corp.This AT89C2051 single-chip microcomputer has a 2k bytes Flash flash memory, full duplex serial communication port and two-stage encipheror storer.
Single-chip microcomputer 1 must carry out reset operation in the time starting, so that its central processing unit and various parts are in predetermined original state.Conventionally single-chip microcomputer adopts to power on and automatically resets and two kinds of reset modes of button hand-reset, powering on automatically resets is that single-chip microcomputer is while powering up, reset circuit adds an of short duration high level signal by electric capacity to RESET pin, and this signal falls after rise gradually along with the charging process of VCC to electric capacity, and the high level lasting time of RESET pin depends on the duration of charging of electric capacity.If the unexpected power down of electric capacity VCC in charging process causes duration of charging deficiency to make single-chip microcomputer can not get active homing, CPU will be since a position executive routine not being defined.Button hand-reset is to adopt between RESET end and VCC to connect a button, the reset of manual operation single-chip microcomputer, and reach tens of milliseconds because manually-operated action also can make button keep connecting again soon, therefore can meet the time requirement of monolithic processor resetting completely.
In the serial extended unit circuit of the present embodiment, adopt button hand-reset mode to carry out reset operation to single-chip microcomputer.As shown in Figure 2, the RESET pin of AT89C2051 single-chip microcomputer is connected with reset circuit, this reset circuit is made up of power supply VCC, capacitor C 1, button S1 and resistance R 1, wherein power supply VCC is connected with the RESET pin of button S1 and chip AT89C2051 by capacitor C 1, again by resistance R 1 ground connection, the capacity of capacitor C 1 is 10uf, and the resistance of resistance R 1 is 10K Ω.
As shown in Figure 2, AT89C2051 single-chip microcomputer is also connected with clock driver circuit, this clock driver circuit is made up of capacitor C 2, capacitor C 3 and quartz crystal, wherein, one end ground connection after capacitor C 2 is in parallel with capacitor C 3, the other end is connected with XTAL2 pin, the XTAL1 pin of AT89C2051 single-chip microcomputer respectively, and quartz crystal is connected between capacitor C 2 and capacitor C 3, the capacity of capacitor C 2 and capacitor C 3 is 22uf, and the oscillation frequency of quartz crystal is 11.0592MHz.
As shown in Figure 2, serial port extended chip 2 adopts the SP3739 chip of Chengdu Shipu Technology Co., Ltd., the two-way I/O mouth of AT89C2051 single-chip microcomputer is connected with address delivery outlet (ADRO) with the input port, address (ADRI) of this SP3739 chip, wherein: P1.2～P1.4 pin of AT89C2051 single-chip microcomputer is connected with address input end mouth ADRI0～ADRI2 pin of SP3739 chip as output port, P1.5～P1.7 pin of AT89C2051 single-chip microcomputer is connected with address output end mouth ADRO0～ADRO2 pin of SP3739 chip as input port.
As shown in Figure 2, the P3.1 pin of AT89C2051 single-chip microcomputer is connected with the RX7 pin of SP3739 chip, this RX7 pin is that the input port of female serial ports COM of SP3739 chip receives the director data from AT89C2051 single-chip microcomputer, the P3.0 pin of described AT89C2051 single-chip microcomputer is connected with the TX7 pin of SP3739 chip, and this TX7 pin is that the output port of female serial ports COM of SP3739 chip sends data to AT89C2051 single-chip microcomputer.
The GND pin ground connection of AT89C2051 single-chip microcomputer, VCC pin connects 5v power supply, and 6,7,8,9,11,12,13 pin are unsettled.
As shown in Figure 2, SP3739 chip is connected with clock driver circuit, this clock driver circuit is made up of capacitor C 4, capacitor C 5 and quartz crystal, wherein, one end ground connection after capacitor C 4 is in parallel with capacitor C 5, the other end is connected with OSCO pin, the OSCI pin of SP3739 chip respectively, and quartz crystal is connected between capacitor C 4 and capacitor C 5, the capacity of capacitor C 4 and capacitor C 5 is 22uf, and the oscillation frequency of quartz crystal is 16.0MHz.
The VCC1 pin of this SP3739 chip is clock power, is connected with a power supply VCC; The GND1 of SP3739 chip is clock ground, passes through capacitor C 6, C7 ground connection with power supply VCC; The VCC2 pin of SP3739 chip is logic power, and VCC is connected with power supply; The GND2 pin of SP3739 chip is logically, passes through capacitor C 8, C9 ground connection with power supply VCC; TX0, the TX1 of SP3739 chip, TX2, TX3, TX4, TX5, TX6 are data receiver port, and wherein TX0 is for receiving the data from host computer, and TX1, TX2, TX3, TX4, TX5, TX6 are for receiving the data from slave computer; RX0, the RX1 of SP3739 chip, RX2, RX3, RX4, TX5, RX6 are data sending terminal mouth, and wherein RX0 is for sending data to host computer, and RX1, RX2, RX3, RX4, TX5, RX6 are for sending data to slave computer.
Although the utility model discloses as above with preferred embodiment, so it is not in order to limit the utility model.Under the utility model, in technical field, have and conventionally know the knowledgeable, not departing from spirit and scope of the present utility model, when being used for a variety of modifications and variations.Therefore, protection domain of the present utility model is when being as the criterion depending on claims person of defining.
Claims (8)
1. a serial extended unit circuit, it is characterized in that, comprise a single-chip microcomputer, a serial port extended chip, a printed circuit board (PCB) and a contact pin circuit, between described single-chip microcomputer and serial port extended chip, be connected by described printed circuit board (PCB), described serial port extended chip is provided with 1 female serial ports COM and 7 sub-serial ports COM0～COM6, and described contact pin circuit controllably switches from outside between the first mode of operation and the second mode of operation:
Under the first mode of operation, described contact pin circuit connects described single-chip microcomputer and a host computer makes its direct communication;
Under the second mode of operation, described contact pin circuit connects host computer and the substring mouth COM0 of serial port extended chip and female serial ports COM of single-chip microcomputer and serial port extended chip;
The substring mouth COM1～COM6 of described serial port extended chip is connected with 6 slave computers respectively, and the data of slave computer collection transfer to single-chip microcomputer by described substring mouth COM1～COM6, and are forwarded to host computer by substring mouth COM0.
2. serial extended unit circuit according to claim 1, is characterized in that, the AT89C2051 single-chip microcomputer that described single-chip microcomputer is atmel corp.
3. the serial extended unit circuit of stating according to claim 2, it is characterized in that, the RESET pin of described AT89C2051 single-chip microcomputer is connected with reset circuit, this reset circuit is made up of power supply VCC, capacitor C 1, button S1 and resistance R 1, wherein power supply VCC is connected with the RESET pin of button S1 and chip AT89C2051 by capacitor C 1, by resistance R 1 ground connection, the capacity of capacitor C 1 is 10uf again, and the resistance of resistance R 1 is 10K Ω.
4. the serial extended unit circuit of stating according to claim 2, it is characterized in that, described AT89C2051 single-chip microcomputer is connected with clock driver circuit, this clock driver circuit is made up of capacitor C 2, capacitor C 3 and quartz crystal, wherein, one end ground connection after capacitor C 2 is in parallel with capacitor C 3, the other end is connected with XTAL2 pin, the XTAL1 pin of AT89C2051 single-chip microcomputer respectively, quartz crystal is connected between capacitor C 2 and capacitor C 3, the capacity of capacitor C 2 and capacitor C 3 is 22uf, and the oscillation frequency of quartz crystal is 11.0592MHz.
5. serial extended unit circuit according to claim 2, it is characterized in that, described serial port extended chip adopts the SP3739 chip of Chengdu Shipu Technology Co., Ltd., the two-way I/O mouth of described AT89C2051 single-chip microcomputer is connected with address delivery outlet with the input port, address of this SP3739 chip, wherein: P1.2～P1.4 pin of AT89C2051 single-chip microcomputer is connected with address input end mouth ADRI0～ADRI2 pin of SP3739 chip as output port, P1.5～P1.7 pin of AT89C2051 single-chip microcomputer is connected with address output end mouth ADRO0～ADRO2 pin of SP3739 chip as input port.
6. serial extended unit circuit according to claim 5, it is characterized in that, the P3.1 pin of described AT89C2051 single-chip microcomputer is connected with the RX7 pin of SP3739 chip, this RX7 pin is that the input port of female serial ports COM of SP3739 chip receives the director data from AT89C2051 single-chip microcomputer, the P3.0 pin of described AT89C2051 single-chip microcomputer is connected with the TX7 pin of SP3739 chip, and this TX7 pin is that the output port of female serial ports COM of SP3739 chip sends data to AT89C2051 single-chip microcomputer.
7. serial extended unit circuit according to claim 5, it is characterized in that, described SP3739 chip is connected with clock driver circuit, this clock driver circuit is made up of capacitor C 4, capacitor C 5 and quartz crystal, wherein, and one end ground connection after capacitor C 4 is in parallel with capacitor C 5, the other end is connected with OSCO pin, the OSCI pin of SP3739 chip respectively, quartz crystal is connected between capacitor C 4 and capacitor C 5, and the capacity of capacitor C 4 and capacitor C 5 is 22uf, and the oscillation frequency of quartz crystal is 16.0MHz.
8. serial extended unit circuit according to claim 5, is characterized in that, the VCC1 pin of described SP3739 chip is clock power, is connected with a power supply VCC; The GND1 of SP3739 chip is clock ground, passes through capacitor C 6, C7 ground connection with power supply VCC; The VCC2 pin of SP3739 chip is logic power, and VCC is connected with power supply; The GND2 pin of SP3739 chip is logically, passes through capacitor C 8, C9 ground connection with power supply VCC; TX0, the TX1 of SP3739 chip, TX2, TX3, TX4, TX5, TX6 are data receiver port, and wherein TX0 is for receiving the data from host computer, and TX1, TX2, TX3, TX4, TX5, TX6 are for receiving the data from slave computer; RX0, the RX1 of SP3739 chip, RX2, RX3, RX4, TX5, RX6 are data sending terminal mouth, and wherein RX0 is for sending data to host computer, and RX1, RX2, RX3, RX4, TX5, RX6 are for sending data to slave computer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320830891.4U CN203644032U (en) | 2013-12-16 | 2013-12-16 | Serial port extender circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320830891.4U CN203644032U (en) | 2013-12-16 | 2013-12-16 | Serial port extender circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203644032U true CN203644032U (en) | 2014-06-11 |
Family
ID=50875260
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320830891.4U Expired - Fee Related CN203644032U (en) | 2013-12-16 | 2013-12-16 | Serial port extender circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203644032U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107168264A (en) * | 2017-06-21 | 2017-09-15 | 北京市环境保护监测中心 | The serial ports shared system and method for environmental monitoring |
| CN108509361A (en) * | 2018-03-29 | 2018-09-07 | 联想(北京)有限公司 | A kind of electronic equipment |
-
2013
- 2013-12-16 CN CN201320830891.4U patent/CN203644032U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107168264A (en) * | 2017-06-21 | 2017-09-15 | 北京市环境保护监测中心 | The serial ports shared system and method for environmental monitoring |
| CN107168264B (en) * | 2017-06-21 | 2019-09-24 | 北京市环境保护监测中心 | The serial ports shared system and method for environmental monitoring |
| CN108509361A (en) * | 2018-03-29 | 2018-09-07 | 联想(北京)有限公司 | A kind of electronic equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI494863B (en) | Dual-interface card reader module | |
| CN204633058U (en) | USB Type-C connector modules | |
| TWI547784B (en) | Method of dynamically adjusting bus clock and device thereof | |
| CN101901201A (en) | Method and device for realizing USB OTG function on electronic equipment | |
| CN102738894A (en) | Modularized intelligent power distribution terminal based on bus port | |
| CN202394228U (en) | USB (Universal Serial Bus) equipment | |
| CN103616935A (en) | Embedded computer mainboard | |
| CN203644032U (en) | Serial port extender circuit | |
| CN203608227U (en) | Bidirectional buffering 1553B/CAN bus protocol converter | |
| CN203552220U (en) | Touch device of multiplex touch display screen | |
| CN113568855A (en) | Low-cost PCIE hot plug multi-mode compatible device | |
| TWM330503U (en) | Flash memory card with dual interface structure | |
| CN202512565U (en) | IOBOX board | |
| CN204480247U (en) | A kind of gigabit networking of arm processor and SATA interface extending device | |
| CN203720584U (en) | Mini-size COM Express processor module based on ARM processor | |
| CN203520299U (en) | Timer-power-on control circuit | |
| CN102779103A (en) | Switching circuit, electronic device and independent display card module | |
| CN102213971A (en) | Time sequence control circuit and front-end bus power supply with time sequence control circuit | |
| CN202025278U (en) | CMOS (complementary metal oxide semiconductor) clear circuit of mainboard | |
| CN111679995B (en) | Embedded management execution unit of space computer based on 1553B bus | |
| CN204633059U (en) | USB Type-C connector modules | |
| CN204706031U (en) | Serial peripheral equipment interface SPI bus circuit and electronic equipment | |
| CN110413550B (en) | Chip serial port program downloading control circuit | |
| CN217060967U (en) | Interface acceleration board card | |
| CN102841877B (en) | Detecting method and automatic detecting circuit of working mode |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140611 Termination date: 20191216 |