projects / pdp8.git / blame
| Commit | Line | Data |
|---|---|---|
| 81e70d48 PH |
1 | /******************************************************************** |
| 2 | /******************************************************************** | |
| 3 | / ASYNCHRONOUS DISPLAY OUTPUT SUPPORT | |
| 4 | ||
| 5 | / THE DISPLAY OPERATES IN AN INTERRUPT DRIVEN MANNER IN ITS OWN | |
| 6 | / THREAD. IF THERE IS NO DISPLAY OPERATION PENDING, IT FALLS | |
| 7 | / ASLEEP. | |
| 8 | ||
| 9 | DINIT, 0 / CALLED BY MAIN THREAD | |
| 10 | TCF / CLEAR TELEPRINTER FLAG | |
| 11 | DCA DTMP / SAVE AC FOR A LITTLE MOMENT | |
| 12 | TAD PDPROC / GET POINTER TO DISPLAY PROCESS ENTRY | |
| 13 | DCA TTOUT / GENERATE RETURN ADDRESS | |
| 14 | DCA TTAC | |
| 15 | DCA TTL | |
| 16 | DCA DFLAGS / CLEAR DISPLAY COMMAND FLAGS | |
| 17 | TAD DTMP / RESTORE CALLER'S AC | |
| 18 | JMP I DINIT / RETURN TO CALLING THREAD | |
| 19 | ||
| 20 | DSUB, 0 / SUBMIT A FLAG TO SET | |
| 21 | CMA | |
| 22 | DCA TMP / SAVE INVERSE OF FLAG | |
| 23 | CLL / CLEAR LINK | |
| 24 | TAD DFLAGS | |
| 25 | SNA | |
| 26 | CML / LINK INDICATES RESTART NOW | |
| 27 | CMA | |
| 28 | AND TMP | |
| 29 | CMA | |
| 30 | DCA DFLAGS / NEW DFLAGS HAVE BEEN INSTALLED. | |
| 31 | SZL / SKIP IF NO LINK | |
| 32 | SPF / SET TTO FLAG -> DISPLAY RESUME | |
| 33 | ION | |
| 34 | JMP I DSUB | |
| 35 | ||
| 36 | /************************************************* | |
| 37 | DPROC, / ENTRY POINT TO THE DISPLAY PROCESS. | |
| 38 | /.... | |
| 39 | ||
| 40 | / TEST, SLEEP, RESTART | |
| 41 | CLA CLL | |
| 42 | TAD DFLAGS | |
| 43 | SZA | |
| 44 | JMP DPROC / WORK TO DO | |
| 45 | TFC / CLEAR FLAG, NO WORK TO DO. | |
| 46 | JMS TTOUT / DUMMY TYPING WITHOUT TLS | |
| 47 | JMP DPROC / AND JUMP BACK TO START OF THREAD | |
| 48 | ||
| 49 | ||
| 50 | ||
| 51 | ||
| 52 | PDPROC, DPROC / POINTER TO DISPLAY PROCESS | |
| 53 | TTAC, 0 | |
| 54 | TTL, 0 | |
| 55 | DTMP, 0 | |
| 56 | ||
| 57 | /******************************************************************** | |
| 58 | / TELETYPE OUTPUT HANDLER AND MANAGEMENT | |
| 59 | ||
| 60 | ||
| 61 | TTOUT, 0 / SEND CHARACTER - CALLED FROM DISPLAY THREAD! | |
| 62 | TSF / IF NO FLAG - GO SLEEPING ONLY | |
| 63 | SKP | |
| 64 | TLS / GET IT OUT! | |
| 65 | DCA TTAC / SAVE AC, JUST POLITE | |
| 66 | RAR | |
| 67 | DCA TTL / SAVE LINK, STILL POLITE | |
| 68 | JMP IEND / END OF INTERRUPT HANDLING | |
| 69 | TTOHAN, TAD TTL | |
| 70 | RAL | |
| 71 | TAD TTAC | |
| 72 | JMP I TTOUT / RESUME DISPLAY THREAD |