|
Routines |
| Prev: 02348 | Up: Map | Next: 02465 |
|
Used by the routine at SAVE_ETC.
The operation of saving a program or a block of data is very straightforward.
|
||||||||||
| SA_CONTRL | 02416 | PUSH HL | Save the 'pointer'. | |||||||
| 02417 | LD A,253 | Ensure that channel 'K' is open. | ||||||||
| 02419 | CALL CHAN_OPEN | |||||||||
| 02422 | XOR A | Signal 'first message'. | ||||||||
| 02423 | LD DE,2465 | Print the message 'Start tape, then press any key.' (see CASSETTE). | ||||||||
| 02426 | CALL PO_MSG | |||||||||
| 02429 | SET 5,(IY+2) | Signal 'screen will require to be cleared' (set bit 5 of TV-FLAG). | ||||||||
| 02433 | CALL WAIT_KEY | Wait for a key to be pressed. | ||||||||
|
Upon receipt of a keystroke the 'header' is saved.
|
||||||||||
| 02436 | PUSH IX | Save the base address of the 'header' on the machine stack. | ||||||||
| 02438 | LD DE,17 | Seventeen bytes are to be saved. | ||||||||
| 02441 | XOR A | Signal 'it is a header'. | ||||||||
| 02442 | CALL SA_BYTES | Send the 'header', with a leading 'type' byte and a trailing 'parity' byte. | ||||||||
|
There follows a short delay before the program/data block is saved.
|
||||||||||
| 02445 | POP IX | Retrieve the pointer to the 'header'. | ||||||||
| 02447 | LD B,50 | The delay is for fifty interrupts, i.e. one second. | ||||||||
| SA_1_SEC | 02449 | HALT | ||||||||
| 02450 | DJNZ SA_1_SEC | |||||||||
| 02452 | LD E,(IX+11) | Fetch the length of the data block that is to be saved. | ||||||||
| 02455 | LD D,(IX+12) | |||||||||
| 02458 | LD A,255 | Signal 'data block'. | ||||||||
| 02460 | POP IX | Fetch the 'start of block pointer' and save the block. | ||||||||
| 02462 | JP SA_BYTES | |||||||||
| Prev: 02348 | Up: Map | Next: 02465 |