Nascom News­let­ter

like to consider writing an article on it for inclusion in a future issue to Nascom News.

2 The LX80 printer

The LX80 is a low-cost 80 character per second printer. It is normally connected to the PIO of any Nascom using suitable cables (extra), and the software described for parallel printers in the last newsletter can be used to control it. A serial version is also available. NAS-SYS/​NAS-DOS users should note that we normally supply the printer with the internal witch 2-3 set for no auto-line feed after a carriage return, so you will need either to set this switch for auto-line feed or add a check in the software drive to output a linefeed (0A ASCII) after each carriage return (OD ASCII). The printer control features associated with the keyboard functions described next month allow for either auto or non-auto linefeed, and a new copy of UTS under NAS-DOS also covers this situation. A modified general purpose parallel printer driver which generates the line feed after a carriage return is listed at the end of this edition of Nascom News.

The printer normally has a maximum print width of 80 characters, but increased and compressed print modes can be initiated by outputting to the printer appropriate escape sequences. In compressed mode up to 142 characters can be printed on each line – very convenient for tabulated output, for example from NAS-CALC.

The printer can also operate in a graphics mode, where each dot is effectively addressable. The AVC software now includes an option for screen dumps to the LX printer, and an example of one of these is attached – the picture was originally generated using NAS-CAD.

Both friction and tractor feed are provided.

A more detailed specification is given in our advertisement. The printer is available from the usual dealers, and may also be found at other outlets.

3 NAS-CAD

NAS-CAD is a computer aided drawing package for use with a Lucas Nascom computer fitted with the Advanced Video Controller (AVC). Development has been carried out on the NAS-DOS version, but a CP/M version will be available soon after the release of the NAS-DOS version. The program is written in Nascom Extended BASIC (XBASIC), but uses machine code routines to increase speed. The program is too large to be entirely in memory, and therefore chaining is used so that only the required parts of the program are in memory at any one time. Loading sections of program from disc can cause brief delays when commands are typed in. However, using the 256K RAM card as a virtual disc under CP/M (this option is available free of charge to registered CP/M users with a 256k RAM card) delays are not noticeable. NAS-CAD