Enhanced BASIC, errata for 25th July 2002 by Lee Davison
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Any command that has an integer first parameter can fail, e.g. try this ..

POKE 760,0 : POKE761,255 PRINT PEEK(760);PEEK(761) 0 255 Ready _

.. so far so good, but now do ..

POKE 761,PEEK(760) PRINT PEEK(760);PEEK(761) 0 255 Ready _

.. which is obviously wrong as both bytes should now be zero.

When BASIC commands have an integer parameter, such as an address, it is stored in the temporary integer word. If, during the evaluation of following parameters, a function that has an integer parameter is called then the temporary integer is overwritten. This can happen with commands such as PEEK, WAIT, BITSET etc.

One routine is changed to fix this, just after LAB_SCGB was ..

LAB_SCGB JSR LAB_1C01 ; scan for "," else do syntax error/warm start JMP LAB_GTBY ; get byte parameter & RET

.. this needs to stack the temporary integer, so it becomes ..

LAB_SCGB JSR LAB_1C01 ; scan for "," else do syntax error/warm start LDA Itemph ; save temporary integer high byte PHA ; on stack LDA Itempl ; save temporary integer low byte PHA ; on stack JSR LAB_GTBY ; get byte parameter PLA ; pull low byte STA Itempl ; restore temporary integer low byte PLA ; pull high byte STA Itemph ; restore temporary integer high byte RTS ;

.. This is done in version 1.05.

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