| MDFS::Software.Video.VTClock | Search | 
 Alan Pemberton wrote this
programme in BBC BASIC in 1983 in order to allow a BBC Microcomputer to
place a countdown and ident clock on video productions. The BBC Micro has a
625-line 50-field 1V composite video output which is suitable for feeding
directly into a video tape recorder. It is also easily modified with a
genlock board so that its signal can be fed synchronously into a video
mixer.
Alan Pemberton wrote this
programme in BBC BASIC in 1983 in order to allow a BBC Microcomputer to
place a countdown and ident clock on video productions. The BBC Micro has a
625-line 50-field 1V composite video output which is suitable for feeding
directly into a video tape recorder. It is also easily modified with a
genlock board so that its signal can be fed synchronously into a video
mixer.
I adapted it to run natively on RISC OS and also on Windows using BBC BASIC for Windows and Alan has given permission for it to appear here.
| CLOCK2 | 12K | BBC BASIC | 
| CLOCK2.BBC | 12K | BBFW | 
| CLOCK2.EXE | 93K | Windows binary | 
The program allows the user to type in the production details on the slate. Use the cursor keys to move around within each box and Shift-Return to move to the next box. The countdown may be started at any ten-second point, and the take number is incremented automatically.
When the clock is at rest, the following keys are recognised:
| |  |  | 
The User Port is set to various values as the countdown progresses. These can be used to control external equipment.
| Each line goes to logical one as follows: | Giving the following bit pattern: |  |