Editing Locomotive BASIC (section)

=== BASIC 1.1 ===
Supplied with the CPC664/6128, besides fixing DEC$, it introduced (among others) the following additional keywords:

COPYCHR$, CURSOR, FILL, FRAME, GRAPHICS PAPER, GRAPHICS PEN and MASK

It also introduced a clumsy but adequate method of trapping disc errors with the <CODE>DERR</CODE> function. Errors still had to be trapped in the usual way with <CODE>ON ERROR GOTO ...</CODE> but the single "Broken In" error 32 could now be expanded to provide more detail. Examining DERR gives up to ten further indicators. Values returned are the AMSDOS error number plus 128, e.g. 14 is reported as a DERR value of 142 (14+128). Possible errors included the usual file not found, disk full etc. as well as the more specific "142 - The stream is not in a suitable state" and "149 - Disc changed while files were open". DERR is a function of BASIC 1.1 and so was not available on the FDI1 expanded CPC464, with its combination of AMSDOS and BASIC 1.0. Disc errors on the CPC464 were obtainable but relied on <CODE>PEEK</CODE>ing into the AMSDOS system area, such program being incompatible with CPC664/6128 due to the AMSDOS variable addresses having moved.