FACING SAME ERROR IN DOING SIMPLE ADDITION IN CHISEL

[BhattSoham]

FACING SAME ERROR IN DOING SIMPLE ADDITION IN CHISEL

[ekiwi]

Actually, it is throwing the same value again and again.

You are always adding 5 and 6 and thus the result is always 11.

[BhattSoham]

Thanks for the reply. Actually, I want to know like if I am passing 5 & 6, I will get the same answer of 11. I just want to know that, suppose there's two conditions, x = x+ 1 & y = y+2 and I want to work it in a loop. I don't want to add manually every time to the chisel test. i want that to be done with the loop. Is that possible in chisel? But whenever I am working on it, it is giving the same result always. Can you please help me with a code?

To be precise, suppose x = 2, y = 3
So, 1st step : x = x + 1 = 3
y = y + 2 = 5

The next step which will be x = 3 + 1 = 4 & y = 5 + 2 = 7. I want this in a loop (not adding it up in chisel test manually). Can it be done?

[schoeberl]

You cannot write x = x + 1 for combinational logic. You need a register in between. HW != SW. Martin

…

On 13 Aug, 2022, at 16:28, BhattSoham ***@***.***> wrote: Thanks for the reply. Actually, I want to know like if I am passing 5 & 6, I will get the error of 11. I just want to know that, suppose there's two conditions, x = x+ 1 & y = y+2 and I want to work it in a loop. I don't want to add manually every time to the chisel test. i want that to be done with the loop. Is that possible in chisel? But whenever I am working on it, it is giving the same result always. Can you please help me with a code? To be precise, suppose x = 2, y = 3 So, 1st step : x = x + 1 = 3 y = y + 2 = 5 The next step which will be x = 3 + 1 = 4 & y = 5 + 2 = 7. I want this in a loop (not adding it up in chisel test manually). Can it be done? — Reply to this email directly, view it on GitHub <#549 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAE63GE67FS6DFJLVRESGWDVY6WHBANCNFSM56NM5S2Q>. You are receiving this because you are subscribed to this thread.

[BhattSoham]

Actually, I have used the register. But the value is coming as it is. Basically, when I am using a loop like

val io = IO(new Bundle {
val x_in = Input(FixedPoint(32.W, 16.BP))
val y_in = Input(FixedPoint(16.W, 8.BP))
val h = Input(FixedPoint(32.W, 16.BP))
val y_out = Output(FixedPoint(32.W, 16.BP))
})
val mx = Reg(FixedPoint(32.W, 16.BP))
for(i<-0 until 5) {
mx := io.y_in + io.x_in
io.x_in := mx
}
io.y_out := mx

}

My question is that it is throwing the same result. and the loop is not rolling. But point is just like in C, we have to denote the 'i' in statement within the loop, but in chisel, it is throwing we cannot use it as because it is fixed point. Any idea?