Is there a more compact way of calculating the number of transactions required?

Asked Feb 15 '17 at 23:44

Active Feb 15 '17 at 23:44

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I need to calculate how many transactions are required to transmit n bytes. I can only read b bytes from the external hardware in a single transaction. The number of transactions is N. This pseudo-code seems sufficient:

If n=0 then
  N=0 // 0 transactions needed as no data has to be transferred IN or OUT
else
  if n%b then
    N=n/b+1 // n is not wholly divisible by b, thus the (last) Nth transaction shall transfer less than b bytes
  else
    N=n/b // all N transactions shall transfer exactly b bytes
  end if
end if

My question is simply, is there a more compact way to do this? I am checking using modulus operator that n%b is nonzero since if I have to transfer 3 bytes and the buffer is 8 bytes, then 3/8 shall be 0 in int but the +1 shall take care of it giving 1 transaction.

asked Feb 15 '17 at 23:44

quantum231

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`N = (n + b - 1) / b;` maybe? – Dmitri Feb 15 '17 at 23:47
See [C rounding integer division (instead of truncating)](https://stackoverflow.com/questions/2422712/) – Jonathan Leffler Feb 15 '17 at 23:50
See Jonathan Leffler's rounding up answer in the linked question. – John Kugelman Feb 15 '17 at 23:51
Aha... hmmmm... I ams dealing with an embedded system design here. No floating point unit. Truncation is ok. That is why I was adding 1. – quantum231 Feb 16 '17 at 08:34
All numbers are unsigned – quantum231 Feb 16 '17 at 08:35

Is there a more compact way of calculating the number of transactions required?

0 Answers0