projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | #ifndef _MC6821_H_ |
| 2 | #define _MC6821_H_ | |
| 3 | ||
| 4 | /* | |
| 5 | * This file describes the memery mapping of the MC6821 PIA. | |
| 6 | * The unions describe overlayed registers. Which of them is used is | |
| 7 | * determined by bit 2 of the corresponding control register. | |
| 8 | * this files expects the PIA_REG_PADWIDTH to be defined the numeric | |
| 9 | * value of the register spacing. | |
| 10 | * | |
| 11 | * Data came from MFC-31-Developer Kit (from Ralph Seidel, | |
| 12 | * [email protected]) and Motorola Data Sheet (from | |
| 13 | * Richard Hirst, [email protected]) | |
| 14 | * | |
| 15 | * 6.11.95 copyright Joerg Dorchain ([email protected]) | |
| 16 | * | |
| 17 | */ | |
| 18 | ||
| 19 | #ifndef PIA_REG_PADWIDTH | |
| 20 | #define PIA_REG_PADWIDTH 255 | |
| 21 | #endif | |
| 22 | ||
| 23 | struct pia { | |
| 24 | union { | |
| 25 | volatile u_char pra; | |
| 26 | volatile u_char ddra; | |
| 27 | } ua; | |
| 28 | u_char pad1[PIA_REG_PADWIDTH]; | |
| 29 | volatile u_char cra; | |
| 30 | u_char pad2[PIA_REG_PADWIDTH]; | |
| 31 | union { | |
| 32 | volatile u_char prb; | |
| 33 | volatile u_char ddrb; | |
| 34 | } ub; | |
| 35 | u_char pad3[PIA_REG_PADWIDTH]; | |
| 36 | volatile u_char crb; | |
| 37 | u_char pad4[PIA_REG_PADWIDTH]; | |
| 38 | }; | |
| 39 | ||
| 40 | #define ppra ua.pra | |
| 41 | #define pddra ua.ddra | |
| 42 | #define pprb ub.prb | |
| 43 | #define pddrb ub.ddrb | |
| 44 | ||
| 45 | #define PIA_C1_ENABLE_IRQ (1<<0) | |
| 46 | #define PIA_C1_LOW_TO_HIGH (1<<1) | |
| 47 | #define PIA_DDR (1<<2) | |
| 48 | #define PIA_IRQ2 (1<<6) | |
| 49 | #define PIA_IRQ1 (1<<7) | |
| 50 | ||
| 51 | #endif |