Setting parity is not possible using smartBASIC on the BL652 and BL654. However, setting parity is supported when working with the Nordic SDK. Therefore, if parity setting is required, the module will have to be programmed using the Nordic SDK and the Nordic examples instead of Laird's smartBASIC examples.
Please refer to the Using the DVK-BL652 and Nordic SDK v14.0.0 with Eclipse & GCC or the Using the BL654 and Nordic SDK v16.0.0 with Eclipse and GCC application note for assistance in setting up the BL652-DVK or BL654-DVK using the Nordic SDK. Please note that Nordic examples work with the external crystal as the clock source. The DVK-BL652 uses the internal RC Oscillator as the clock source, therefore if you will not be fitting the low frequency external crystal please be sure to modify the Nordic examples as explained in the above application note. You may also wish to refer to the BL652 Dev Kit User Guide or the BL654-DVK User Guide & Quick Start Guide