cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 
araongao2015
Explorer
Explorer
3,142 Views
Registered: ‎11-01-2015

How to define the register depth if I add an IO register for the top-level scalar

Jump to solution

Hi,

 

When I try to add an IO register for the top-level scalar, there is a parameter -depth. But I find it can only be used for ap_fifo to set the depth of FIFO. So I want to know can I set the depth of register to create a cascaded registers.

 

Thanks,

Regards

0 Kudos
Reply
1 Solution

Accepted Solutions
pupkin
Observer
Observer
5,309 Views
Registered: ‎09-10-2016

It is all about implementing handshaking signals xxx_vld and xxx_ack (default ap_ctrl_hs mode).

With no register, handshaking is trivial.

With 1 register, handshaking is a bit more complicated (at any time there is either 0 or 1 value "in transit")

With >1 register depth, you'd need a proper FIFO to get the handshaking signals right.

 

Regards,

VP

 

View solution in original post

4 Replies
u4223374
Advisor
Advisor
3,134 Views
Registered: ‎04-26-2015

Isn't this just a register array? For that you just need to put an array on the interface.

0 Kudos
Reply
araongao2015
Explorer
Explorer
3,106 Views
Registered: ‎11-01-2015

Hi,

 

Below is the GUI of adding IO register in Vivado HLS.  I just want to add register to an IO. The main issue is how to set the depth of register. Here the -depth cannot be used to get this goal.

 

Thanks,

Regards

 

 

add_reg.JPG

0 Kudos
Reply
pupkin
Observer
Observer
5,310 Views
Registered: ‎09-10-2016

It is all about implementing handshaking signals xxx_vld and xxx_ack (default ap_ctrl_hs mode).

With no register, handshaking is trivial.

With 1 register, handshaking is a bit more complicated (at any time there is either 0 or 1 value "in transit")

With >1 register depth, you'd need a proper FIFO to get the handshaking signals right.

 

Regards,

VP

 

View solution in original post

araongao2015
Explorer
Explorer
3,044 Views
Registered: ‎11-01-2015

Hi @pupkin

 

I get a clear perspective of it now. Thank you for your explanation.

0 Kudos
Reply