How can I specify the data type of the output of an Extract Bits block in Simulink 6.1 (R14SP1)?

Instead of having the Extract Bits block output a fixed point data type of the appropriate size, I would like to be able to specify the output data type. For example, if the input is a uint8 and the upper half bits are being extracted, the output will be of type ufix4_E4. I would like to be able to specify the output as a zero-padded uint8.

Answer 1

[MathWorks Support Team]

The ability to specify the output type of the Extract Bits block is not available in Simulink.

To work around this issue, use a combination of Shift Arithmetic and Bitwise AND blocks to extract the bits.

For example, to extract the upper 4 bits of a uint8 signal, pass it through a Shift Arithmetic block that shifts 4 positions to the right followed by a Bitwise AND with 0x0F. The model below, extractbits.mdl, illustrates how this can be done.