SAR ADC data sheet | Cypress Semiconductor
SAR ADC data sheet
I just found out that the description of the SAR ADC registers is somewhat misleading (and has changed from earlier versions) for the PSoC5. It says that the result can be between 8 and 12 bits. This would imply that an 8but-ADC uses only the ADC_SAR_WRK0_REG register. But this isn't the case - the result here is always 12bits (as it is stated in the component parameter section elsewhere).
This problem especially affect the usage of DMA - it always must transfer both bytes of the results register, and therefore needs more memory.
In earlier versions this was different - I just found this out when I migrated my admScope project to the newest Creator version.