| APB_S_PSEL | In | High | Indicates APB slave select |
| APB_S_PENABLE | In | High | Indicates APB enable |
| APB_S_PWRITE | In | High | APB write-control signal. Indicates read when
Low and write when High. |
| APB_S_PADDR [10:2] | In | | Indicates APB address. Addresses are
word-aligned. |
| APB_S_PWDATA [15:0] | In | | Indicates APB write data |
| APB_S_PRDATA [15:0] | Out | | Indicates APB read data |
| APB_S_PREADY | Out | | Indicates APB PREADY signal and is used to extend an APB transfer. |
| APB_S_PSLVERR | Out | High | Indicates a transfer failure |
| APB_S_PCLK | In | | Indicates APB clock |
| APB_S_PRESET_N | In | Low | Indicates APB active-low reset |
