| 1 | # |
| 2 | /* |
| 3 | */ |
| 4 | |
| 5 | /* |
| 6 | * VT01 driver via DR11C to 11/20 |
| 7 | */ |
| 8 | |
| 9 | #include "../param.h" |
| 10 | #include "../user.h" |
| 11 | |
| 12 | int vtflag; |
| 13 | |
| 14 | struct vtreg { |
| 15 | int csr; |
| 16 | int buf; |
| 17 | }; |
| 18 | |
| 19 | #define VTADDR 0167770 |
| 20 | #define RQINT 01 |
| 21 | #define BIENABL 040 |
| 22 | #define SEOF 0100000 |
| 23 | #define VTPRI 8 |
| 24 | |
| 25 | vtopen(dev, flag) |
| 26 | { |
| 27 | if (!flag) |
| 28 | u.u_error = ENXIO; |
| 29 | else |
| 30 | VTADDR->csr = BIENABL; |
| 31 | } |
| 32 | |
| 33 | vtclose() |
| 34 | { |
| 35 | VTADDR->buf = SEOF; |
| 36 | VTADDR->csr =| RQINT; |
| 37 | } |
| 38 | |
| 39 | vtwrite() |
| 40 | { |
| 41 | register int c; |
| 42 | int register count; |
| 43 | |
| 44 | while ((c=cpass()) >= 0) { |
| 45 | retry: |
| 46 | for (count=0; count<10; count++) |
| 47 | if ((VTADDR->csr&RQINT)==0) { |
| 48 | VTADDR->buf = c&0377; |
| 49 | VTADDR->csr =| RQINT; |
| 50 | goto contin; |
| 51 | } |
| 52 | spl5(); |
| 53 | if (VTADDR->csr&RQINT) { |
| 54 | vtflag++; |
| 55 | sleep(VTADDR, VTPRI); |
| 56 | } |
| 57 | spl0(); |
| 58 | goto retry; |
| 59 | contin:; |
| 60 | } |
| 61 | } |
| 62 | |
| 63 | vtintr() |
| 64 | { |
| 65 | VTADDR->csr =& ~RQINT; |
| 66 | if (vtflag) { |
| 67 | vtflag = 0; |
| 68 | wakeup(VTADDR); |
| 69 | } |
| 70 | } |