1. Open `Z-Stack Home 1.2.2a.44539\Projects\zstack\ZNP\CC253x\znp.eww` with IAR Embedded workbench for 8051.
2. You will get a warning: *The project file 'CC253(0/1).ewp' is in an old format. Would you like to convert it for use with this version?*. Press **yes** for both.
3. In the dropdown, set target to *CC2531 - ProdHex*.