Rounding (SPEEDY-33, DSP Module)
Digital signal processors (DSPs) and general-purpose processors, such as the processors in desktop computers, differ from each other. The SPEEDY-33 target and LabVIEW perform floating-point to integer conversions differently because of the way the SPEEDY-33 rounds the values.
For example, the To Long Integer function rounds all floating-point numeric values to the nearest integer when the VI is open in a My Computer application instance. If the fractional part of the floating-point value is .5, the function rounds the value to the nearest even integer. For example, the function rounds 13.5 to 14 and rounds 14.5 to 14.
The SPEEDY-33 rounds the value to the nearest integer, which is not necessarily the nearest even integer. Refer to the following table for an example of the difference in rounding.
| Value | SPEEDY-33 | Windows |
|---|---|---|
| 8.5 | 9 | 8 |
| 9.5 | 10 | 10 |
Refer to the TMS320C3x User’s Guide for more information about floating-point conversion on the SPEEDY-33. Visit www.ti.com and search for SPRU031 to download a copy of the TMS320C3x User’s Guide.