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| documentation:monitor:directpage [2014/03/22 19:25] – created pulkomandy | documentation:monitor:directpage [2014/03/22 21:02] – [3A: TEMPO] pulkomandy | ||
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| ===== 3A: TEMPO ===== | ===== 3A: TEMPO ===== | ||
| + | Note length multiplier | ||
| + | ===== 3C: DUREE ===== | ||
| + | Note length | ||
| + | ===== 3D: WAVE ===== | ||
| + | Sound wave shape (values from 0 to 5) | ||
| + | ===== 3E: OCTAVE ===== | ||
| + | Note octave multiplier (16, 8, 4, 2, 1, from bass to treble) | ||
| + | ====== Tape drive ====== | ||
| + | Note: this needs a tape drive. | ||
| + | ===== 40: K7DATA ===== | ||
| + | Byte being read or written to tape | ||
| + | ===== 41: K7LENG ===== | ||
| + | Byte counter for current block being written to tape | ||
| + | ====== Printer ====== | ||
| + | Note: this needs a printer port, which is an extension on some machines. | ||
| + | ===== 42: PROPC - Printer Operation Code ===== | ||
| + | ===== 43: PRSTA - Printer status ===== | ||
| + | * 4: port open | ||
| + | * 8: ready | ||
| + | * 10: port closed | ||
| + | ====== System support ====== | ||
| + | ===== 44-45: TEMP - Temporary register ===== | ||
| + | Used as temporary storage by various routines. | ||
| + | ===== 46-47: SAVEST - System stack pointer backup ===== | ||
| + | S register is saved here when a routine needs to modify it. | ||
| + | ====== Disk operations ====== | ||
| + | These variables are only used by the floppy controller ROM, not the monitor one. | ||
| + | ===== 48: DKOPC - Disk Operation ===== | ||
| + | Used by DKCONT system call. Possible operations: | ||
| + | * 1: initialize controller | ||
| + | * 2: read a sector | ||
| + | * 4: switch to single density | ||
| + | * 8: write a sector | ||
| + | * 10: switch to double density | ||
| + | * 20: seek track 0 | ||
| + | * 40: seek track | ||
| + | * 80: verify sector. | ||
| + | Some of these can be combined (88 is "write and verify sector" | ||
| + | ===== 49: DKDRV - Active drive ===== | ||
| + | * 0: Drive A, top side | ||
| + | * 1: Drive A, bottom side | ||
| + | * 2: Drive B, top side | ||
| + | * 3: Drive B, bottom side | ||
| + | * 4: RAM disk | ||
| + | ===== 4A-4B: DKTRK - Disk track ===== | ||
| + | This is a 16 bit variable because of the use on QDD as the " | ||
| + | ===== 4C: DKSEC - Disk sector number ===== | ||
| + | ===== 4D: DKNUM - Sector interleaving factor ===== | ||
| + | The default is 7, which lays out the sectors in this order: | ||
| + | 0, | ||
| + | ===== 4E: DKSTA - Disk status ===== | ||
| + | Used as error bits after executing disk operations: | ||
| + | * bit 0: write protection | ||
| + | * bit 1: track error | ||
| + | * bit 2: sector error | ||
| + | * bit 3: data error | ||
| + | * bit 4: drive not ready, no disk or motor off | ||
| + | * bit 5: compare error (data read from disk and memory version are different) | ||
| + | * bit 6: not formatted | ||
| + | |||
| + | Used as information about the type of controller aftre initialisation: | ||
| + | * 43 (' | ||
| + | * 44 (' | ||
| + | |||
| + | ===== 4F-50: DKBUF - Disk buffer ===== | ||
| + | Pointer to 256 byte work buffer for the floppy controller | ||
| + | |||
| + | ===== 51-58: working area ===== | ||
| + | Used for several different purposes by the floppy ROM. | ||
| + | |||
| + | ====== Keyboard scanning, interrupts, custom character tables ====== | ||
