[Moved] How to read TTL Signal from sensor with Microcontroller ?

[Renuka0007]

Can any one help me to read TTL signal(5V TTL-Compatible) to read with Microcontroller ?I am having Pressure sensor with output TTL. Sensor having 3 pins One is Vcc ,GND and Signal(5v -TTL Compatible ).

I am using stm32 Nucleo board . Please suggest me how to read it .

Thanks,

 

[KlausST]

[Moved] Re: How to read TTL Signal from sensor with Microcontroller ?

Hi,

To get a good and reliable answer you should:
* give us the exact type and vendor of the sensor, or (a link to) the datasheet
* give us the exact type and vendor of the microcontroller, or (a link to) the datasheet
* the schematic, with addition information like: voltages, part values...

In detail:
V_OH of the sensor needs to be compatible with V_IH and V_Imax of the microcontroller.
(V_low usally is not problematic, but it's a good idea to check it, too)
Often the voltage levels depend on circuitry and power supply voltage.

You say "5V TTL compatible"...
But is it a true push pull TTL output, or just "TTL compatible"?
A true TTL output drives a HIGH signal higher than 2.0V, whereas a "compatible" output can be a "open collector" whuch needs an external pullup resistor to get valid HIGH levels.

Klaus

 

[Renuka0007]

Re: [Moved] Re: How to read TTL Signal from sensor with Microcontroller ?

Thanks for your reply,

Micro controller link -- https://www.st.com/en/evaluation-tools/nucleo-l073rz.html

Sensor vendor link -- **broken link removed**


Please let me know the inputs to read the data with MCU.

 

[Renuka0007]

Hi,

The sensor datasheet just says "5V TTL (compatible)" ouput.
Thus it should be
LOW: <0.4V
HIGH: >2.4V
according TTL standard.
(You could easily find the values on your own: Just do an internet search for "TTL voltage levels")


This is not what I was asking for.

Please show a little effort on your own: Read the microcontroller (not the evaluation board) datasheet and find out V_IH and V_Imax. (as already meantioned in post#2)

Mind: The signal is no "digtal data" signal. It´s just a frequeny. --> you need to do a frequency measurement.

Klaus

Thanks for your reply ,

I have tried it on my own only ,but everywhere i am seeing what is a TTL signal couldn't find how to interface read them with any MCU .
If you could explain me that would be really appreciated .

Can i able to read this signal using ADC of micro controller before that many docs i found that TTL is nothing but a native serial .I don't have clarification on it .

Kindly help to solve this .

Thanks,

 

[KlausST]

[Sorry for the confused order of posts]

Hi,

The sensor datasheet just says "5V TTL (compatible)" ouput.
Thus it should be
LOW: <0.4V
HIGH: >2.4V
according TTL standard.
(You could easily find the values on your own: Just do an internet search for "TTL voltage levels")

Micro controller link -- **broken link removed**

This is not what I was asking for.

Please show a little effort on your own: Read the microcontroller (not the evaluation board) datasheet and find out V_IH and V_Imax. (as already meantioned in post#2)

Mind: The signal is no "digtal data" signal. It´s just a frequeny. --> you need to do a frequency measurement.

Klaus

- - - Updated - - -

Hi,

I have tried it on my own only ,but everywhere i am seeing what is a TTL signal couldn't find how to interface read them with any MCU .
If you could explain me that would be really appreciated .

I won´t look for the datasheet, download it and search the document for "V_IH"...
It is your job, and if you want others do your job you should consider to pay for this.
But even for this you need to give the requested information: exact type of microcontroller.

It is a simple task you need to be able to do this on your own.
With almost every datasheet there is a section "electrical characteristics" ... there it should be easy to find "V_IH".

Klaus