Wrong computation in BSP_MS_TO_TICK macro

Question

Hi, 
 I noticed a possible issue in BSP_MS_TO_TICK macro computation.
In bsp.c, the macro is defined as: 
 #define BSP_MS_TO_TICK(MS) (m_app_ticks_per_100ms * (MS / 100))
 
 This macro is used many places in BSP to start timers.
But due to the places of parenthesis, it forbid the usage of timers shorter than 100ms.
It does a division of MS by 100, leading to 0 if MS < 100. 
 Rather than: 
 #define BSP_MS_TO_TICK(MS) ((m_app_ticks_per_100ms * MS) / 100)
 
 It shall be (mind the place of the parenthesis): 
 #define BSP_MS_TO_TICK(MS) (m_app_ticks_per_100ms * (MS / 100))
 
 Multiply before divide is probably better to avoid 0 tick computation when MS < 100ms. 
 Is it on-purpose ?
Can you confirm there is no issue setting timers shorter than 100ms ? (I think/hope not). 
 Regards.
Djamil

Susheel Nuguru · Accepted Answer

If this was in a header file, then I would have agreed with you.
I am not happy with the paranthesis either, but we cannot call this a bug.
This is because this macro is defined in bsp.c file. and all the values used within this module are multiples of 100. So I think it is what the developer intended. 
 If you want changing anything in this file, then you can change the parenthesis to suit your needs.
I can confirm that anything less than 100ms would not work as you said, and i also confirm that the module as it is should work fine with all intervals being multiples of 100.

Wrong computation in BSP_MS_TO_TICK macro

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