Summary of the invention
Level conversion provided by the invention system can export the level of a plurality of varying level standards according to the level signal of a level standard in same system.
For solving the problems of the technologies described above, the invention provides following technical scheme:
A kind of level conversion system, the first fiduciary level signal that is used for the varying level chip is sent converts the second corresponding fiduciary level signal to, this system comprise an input interface, a processor, a control circuit and with level chip a plurality of level conversion subsystems one to one, wherein each level conversion subsystem comprise one or more conversion equipments and with a plurality of conversion equipments switching circuit one to one, each level chip links to each other with described one or more conversion equipments, wherein:
Described input interface is used for the identification information of incoming level chip and the identification information of the second fiduciary level signal;
Described processor, link to each other with described input interface, be used for the identification information according to described level chip, determine the conversion equipment that links to each other with described level chip, from the conversion equipment that described and described level chip links to each other, determine Target Transfer Unit, generate control signal;
Described control circuit links to each other with each switching circuit with described processor, is used for according to the described control signal control switching circuit conducting corresponding with described Target Transfer Unit;
Described Target Transfer Unit is used for the described first fiduciary level signal is converted to the described second fiduciary level signal and outputs to external equipment.
Preferably, described switching circuit is relay, and the contact of described relay links to each other with described conversion equipment; Wherein, described control circuit is controlled the contact adhesive of the relay of described Target Transfer Unit correspondence.
Described switching circuit is diode, triode or analog switch,
Wherein, described control circuit is controlled diode, triode or the analog switch conducting of described Target Transfer Unit correspondence.
Preferably, described processor is CPLD.
Technical scheme provided by the invention, the first fiduciary level signal of level chip output is converted to the signal of other level standards by conversion equipment, manage by the conducting state to the ON-OFF control circuit that links to each other with conversion equipment again, thereby guarantee in same system, to export according to the level signal of a level standard level of a plurality of varying level standards.
Because relay contact resistance is very little, has only the impedance at several ohm of zero points, and no any electric signal on the relay contact, therefore for a signal transmission more than several volts, almost there is not loss, realized the harmless transmission of signal from physical layer.
Embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, the present invention is described in further detail below in conjunction with the accompanying drawings and the specific embodiments.
Fig. 1 is the structural representation of level conversion system embodiment provided by the invention.System shown in the system shown in Figure 1 embodiment, the first fiduciary level signal that is used for the level chip is sent converts the second fiduciary level signal to, this system comprise an input interface, a processor, a control circuit, a plurality of conversion equipment and with a plurality of conversion equipments switching circuit one to one, described level chip links to each other with described a plurality of conversion equipments, wherein:
Described input interface is for the identification information that receives the second fiduciary level signal;
Described processor links to each other with described input interface, is used for according to described identification information, determines to generate control signal by Target Transfer Unit from described a plurality of conversion equipments;
Described control circuit links to each other with each switching circuit with described processor, is used for according to the described control signal control switching circuit conducting corresponding with described Target Transfer Unit;
Described Target Transfer Unit is used for the described first fiduciary level signal is converted to the described second fiduciary level signal and outputs to external equipment.
System embodiment provided by the invention, the first fiduciary level signal of level chip output is converted to the signal of other level standards by conversion equipment, manage by the conducting state to the ON-OFF control circuit that links to each other with conversion equipment again, thereby guarantee in same system, to export according to the level signal of a level standard level of a plurality of varying level standards.
With an application example system embodiment provided by the invention is described further below:
In each conversion equipment, load to be used for first fiduciary level is converted to the program of various criterion level signal, and the program that loads of each conversion equipment inequality in twos, with so that the standard of the level signal that conversion equipment is converted to inequality in twos.At present, level standard comprises standard TTL 5V level standard, standard TTL 3.3V level standard, RS422 differential level standard and LVDS differential level standard.The program that in the prior art above-mentioned four kinds of level standards is carried out at the level standard of switching levels signal all is applicable to the present invention, repeats no more herein.
Can the level signal of other standards that conversion equipment is converted to output to external equipment, depend on the whether conducting of the switching circuit that links to each other with this conversion equipment, and its whether conducting is controlled by control circuit, and processor that control circuit is based on is judged the standard current needs whether of the level signal of this conversion equipment output, if wherein think needs, the switching circuit conducting of then notifying control circuit allow this conversion equipment correspondence makes this conversion equipment that the level signal that is converted to is outputed to external equipment; Otherwise, can anyly not handle.Wherein this conversion equipment can be one to be loaded with the chip of the program of switching levels standard, also can be a hardware circuit.
Wherein said processor can be CPLD, can design a control register by this device inside, writes different controlling values at control register in advance, and disposes each controlling value and represent to switch to different level standards.When subsequent operation, can judge the level standard that needs according to the current numerical value that writes.For example, when the value of control register was written as 0x000, the expression system need switch to the 5V level standard of Transistor-Transistor Logic level standard; When the value that writes was 0x100, expression need switch to the 3.3V level standard of TTL; When the value that writes was 0x001, expression need switch to the RS422 level standard; When the value that writes was 0x002, expression need switch to the LVDS level standard.If the current numerical value that writes is 0x001, then need to switch to the RS422 level standard.
For this system also can export the level standard of this level chip output, switching device directly can be linked to each other with the level chip, by this switching device, control the level standard that whether makes the level chip whether export this level chip to the outside.
Behind the level standard that obtains need switching, processor can determine to export the conversion equipment of the level signal of this level standard, the switching device conducting that can notify control circuit to drive this conversion equipment from conversion equipment.
Wherein this switching device can be relay, and namely the contact of relay links to each other with described conversion equipment.Control circuit is realized switching function by the contact adhesive of control relay with disconnection.Wherein the mode by the circuit control relay switch all is applicable to the present invention in the prior art, repeats no more herein.
Because relay contact resistance is very little, has only the impedance at several ohm of zero points, and no any electric signal on the relay contact, therefore for a signal transmission more than several volts, almost there is not loss, so realized the harmless transmission of signal from physical layer.
Certainly, also be not limited thereto, for the volt of signal when very big, when the loss of voltage can be ignored, this switching device can be for having the components and parts of conducting voltage, as diode, triode and analog switch, this control circuit corresponding with these components and parts can be a power supply, be used for when components and parts need conducting, for these components and parts provide voltage, making this components and parts conducting.
Fig. 2 is the structural representation of another kind of level conversion provided by the invention system.In conjunction with system embodiment shown in Figure 1, this system shown in Figure 2 embodiment, the first fiduciary level signal that is used for the varying level chip is sent converts the second corresponding fiduciary level signal to, this system comprise an input interface, a processor, a control circuit and with level chip a plurality of level conversion subsystems one to one, wherein each level conversion subsystem comprise one or more conversion equipments and with a plurality of conversion equipments switching circuit one to one, each level chip links to each other with described one or more conversion equipments, wherein:
Described input interface is used for the identification information of incoming level chip and the identification information of the second fiduciary level signal;
Described processor, link to each other with described input interface, be used for the identification information according to described level chip, determine the conversion equipment that links to each other with described level chip, from the conversion equipment that described and described level chip links to each other, determine Target Transfer Unit, generate control signal;
Described control circuit links to each other with each switching circuit with described processor, is used for according to the described control signal control switching circuit conducting corresponding with described Target Transfer Unit;
Described Target Transfer Unit is used for the described first fiduciary level signal is converted to the described second fiduciary level signal and outputs to external equipment.
Wherein said switching circuit comprises relay, and the contact of described relay links to each other with described conversion equipment; Described control circuit is controlled the contact adhesive of the relay of described Target Transfer Unit correspondence.
Wherein said processor is CPLD.
Different with system embodiment shown in Figure 1 is, present embodiment can be changed the level signal of multiple level standard, and namely every kind of level signal all has the level shifted signal corresponding with it, more can satisfy user's needs.
The all or part of step that one of ordinary skill in the art will appreciate that above-described embodiment can use the computer program flow process to realize, described computer program can be stored in the computer-readable recording medium, described computer program (as system, unit, device etc.) on corresponding hardware platform is carried out, when carrying out, comprise one of step or its combination of method embodiment.
Alternatively, all or part of step of above-described embodiment also can use integrated circuit to realize, these steps can be made into integrated circuit modules one by one respectively, perhaps a plurality of modules in them or step is made into the single integrated circuit module and realizes.Like this, the present invention is not restricted to any specific hardware and software combination.
Each device/functional module/functional unit in above-described embodiment can adopt the general calculation device to realize, they can concentrate on the single calculation element, also can be distributed on the network that a plurality of calculation elements form.
Each device/functional module/functional unit in above-described embodiment is realized with the form of software function module and during as independently production marketing or use, can be stored in the computer read/write memory medium.The above-mentioned computer read/write memory medium of mentioning can be read-only memory, disk or CD etc.
The above; only be the specific embodiment of the present invention, but protection scope of the present invention is not limited thereto, anyly is familiar with those skilled in the art in the technical scope that the present invention discloses; can expect easily changing or replacing, all should be encompassed within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the described protection range of claim.