JEDEC JEP106BF.01 PDF

The manufacturer’s identification code is defined by one or more eight (8) bit fields each consisting of seven (7) data bits plus one (1) odd parity bit. It is a single field limiting the possible number of vendors to 126. To expand the maximum number of identification codes a continuation scheme has been defined. The code 7F as shown in Table 1 indicates that the manufacturer’s code is beyond the limit of this field and the next sequential manufacturer’s identification field is used. Multiple continuation fields are permitted and when used shall comprise of the identification code.