BIT0 option

An option that prevents certain warning messages if you use the lowest-numbered bit of a group as anything other than the LSB.

When you declare a group with a range of numbers, the first number listed is always the MSB, the last is always the LSB. If you specify a range in ascending order, a warning message is issued unless you have used the BIT0 option to specify that the lowest numbered bit is the MSB. If you set the BIT0 option to MSB, a warning message is generated if you specify a range in descending order. If you set BIT0 to ANY, you may specify ranges in either ascending or descending order without receiving a warning.