This characteristic sets the source handshake T1 delay of the GPIB interface. This delay determines the minimum amount of time, after the data is placed on the bus, that the board must delay before asserting the GPIB DAV line during a write or command operation. Refer to Section 5.2 of the ANSI/IEEE Standard 488.1-1987 for more information about the factors that might affect the choice of T1 delay. For example, if the total length of the GPIB cable in the system is less than 15 m, the value 350 ns is appropriate. The default bus timing selection, 500 ns, should work in all systems.