Pmod con 3 ip core

[nattib]

Hi all,

I would like to control a servo through a microblaze application. I saw that there is a Pmod for this, here on digilent. I gather its the Pmod CON3. the problem is that I can t find its ip core anywhere in the vivado library (i use vivado 2016.4). can anyone please point me to it?

thanx. nattib

[jpeyron]

Hi @nattib,

We have not had time to make a Pmod CON3 IP Core. We do have a VHDL demo for the Pmod CON 3 on the resource center here. To use the Pmod CON 3 with microblaze you will need to us the add a module function with the VHDL in the Vivado block design which allows VHDL/Verilog code to work with microblaze. Here is a forum thread that discusses doing this with a zynq processor. The process will be the same with microblaze.

thank you,

Jon

[nattib]

Hi Jon,

Thanks a lot. I ll try and see if i manage to do it...thanksagain

is "add a HDL block" the same as "add a module" ? this one give the only possibility of a RTL type module

I just have run over the example notarobot but i m still completely in the dark: i can t guess how to do it.

in the link you provided i can see a vhdl component for the pmod con3. is this the one i have to use as a added module? or should write my own?

[nattib]

Hi again,

after having a look at the pmod con3 schematic I wonder what would an IP serves for? it looks like just adding a series resistor between the driver signal and the pmod connectror pin with only configuration to set the source of the power line. now i wonder, since i am generating my pwm control signal from the microblaze  timer, can't I just connect the timer output to the corresponding connector pin? 

apologies for adding new questions without waiting for answers

[jpeyron]

Hi @nattib,

Looking at the schematic for the Pmod CON3 i believe you are correct. As long as you can generate the signal that your servo's need then you would not need to use the add module function by right clicking on a empty part in the block design along with using the HDL code for the Pmod CON3  linked above.

thank you,

Jon

[nattib]

thank you for answering Jon,

but now, can I connect the timer pin directly to th Pmod connetor pin? should I make it external and then constraint it or do i have to wrap my design first and then connect to the pin ?

[jpeyron]

Hi @nattib,

I would use create port and then constrain through xdc. I have attached some screen shots.

thank you,

Jon

[nattib]

thanks a lot Jon, I'll go with that!!

[Nachiket Karve]

Shouldn't it also be possible to control the Pmod CON 3 using the PmodGPIO IP core?

[jpeyron]

Hi @Nachiket Karve,

You could use the PmodGPIO IP core to communicate to the Pmod CON3 . Within this IP core you would still need to create the pulse width modulation needed for the servo.

thank you,

Jon