Nascom News­let­ter

Since the release of the tape version of Nascom Enhanced BASIC a number of minor problems have come to light, both in the interpreter and the manual. These have now all been corrected, but if you have one of the earlier copies you should check whether the following bugs have been corrected. When you have made any necessary corrections you should save a new copy using the W1000 4200 command in NAS-SYS (remember you should not copy over your original in case you made a mistake making these changes!)

4.1 Keyboard operation

KBD and KBD$ only work for shifted characters.

Modify 1439 (was 38) to 20

Auto repeat works correctly with INCH, but not with KBD. This is due to the fast keyboard check that is used between statements. You can enable auto-repeat with KBD as follows:

Modify 3A4F (was E3) to FE

Note, however, that this slows down execution by about 10% and so should be used with care and certainly NOT as a permanent modification.

4.2 ON ERR GOSUB

An error occurs after ON ERR GOSUB which results in a return to the monitor.

Modify 1652 (was C1) to: FE 90 20 18 2A 57 10 C1 C5 F5 7E B7 20 04 23 23 23 23 23 F1 E5 2A 51 10 E5 F5 33 C5

4.3 Tape system

Verify fails on data files of only one block length.

Modify 37DB (was 38) to 18 03

Tape loading and verification leaves the tape LED lit after an error has occurred.

Modify 3D53 (was CD) to 38 41
Modify 3D78 (was CD) to 38 41
Modify 4138 (was 00) to DF 5F C3 CD 15

4.4 RND function

The use of RND with a real argument of between 0 and 1, while of no particular use, causes the system to lock-up. In addition the use of negative numbers in the arguments (also of no particular use) returns a constant, rather than giving the error which it should.

Modify 2E01 (was 1B) to F7 24 7A B3 28 04 ED 53 1F 10 18 03