National Instruments GPIB-PC - page 101

BASICA/QuickBASIC GPIB-PC Function Calls Section Four A
GPIB-PC User Manual 4A-26 ©National Instruments Corp.
BASICA/QuickBASIC BASICA/QuickBASIC
IBEOS IBEOS
Purpose: Change or disable end-of-string termination mode
Format: CALL IBEOS (BD%,V%)
Remarks: BD% specifies a device or an interface board. V% specifies
the EOS character and the data transfer termination method
according to Table 4A.5. IBEOS is needed only to alter the
value from its configuration setting.
The assignment made by this function remains in effect
until IBEOS is called again, the IBONL or IBFIND
function is called, or the system is rebooted.
When IBEOS is called and an error does not occur, the
previous value of V% is stored in IBERR%.
Table 4A.5 - Data Transfer Termination Method
Method Value of V%
High Byte Low Byte
A. Terminate read when EOS 00000100 EOS
is detected
B. Set EOI with EOS on write 00001000 EOS
function
C. Compare all 8 bits of EOS 00010000 EOS
byte rather than low 7 bits
(all read and write functions)
Methods A and C determine how read operations terminate.
If Method A alone is chosen, reads terminate when the low
7 bits of the byte that is read match the low 7 bits of the
EOS character. If Methods A and C are chosen, a full 8-bit
comparison is used.