System SourceMeter® Instrument Reference Manual  Section 7: 
 
2600BS-901-01 Rev. C / August 2016  7-65 
 
Details 
The binary representation of data indicates the output pattern to be written to the I/O port. For 
example, a data value of 170 has a binary equivalent of 00000010101010. Lines 2, 4, 6, and 8 are 
set high (1), and the other 10 lines are set low (0). 
Write-protected lines are not changed. 
The reset() function does not affect the present states of the digital I/O lines. 
Use the digio.writebit() and digio.writeport() commands to control the output state of 
the synchronization line when trigger operation is set to digio.TRIG_BYPASS. 
 
Example 
 
Sets digital I/O Lines 1 through 8 high (binary 
 
Also see 
digio.readbit() (on page 7-54) 
digio.readport() (on page 7-54) 
digio.writebit() (on page 7-64) 
digio.writeprotect (on page 7-65) 
 
digio.writeprotect 
This attribute contains the write-protect mask that protects bits from changes from the digio.writebit() and 
digio.writeport() functions. This attribute is not available on the Models 2604B/2614B/2634B. 
Type  TSP-Link accessible  Affected by  Where saved  Default value 
Attribute (RW)  Yes  Instrument reset 
Recall setup 
Saved setup  0 
 
Usage 
mask = digio.writeprotect 
digio.writeprotect = mask 
 
Sets the value that specifies the bit pattern for write-protect 
 
Details 
Bits that are set to one cause the corresponding line to be write-protected. 
The binary equivalent of mask indicates the mask to be set for the I/O port. For example, a mask 
value of 7 has a binary equivalent of 00000000000111. This mask write-protects lines 1, 2, and 3. 
 
Example 
 
Write-protects lines 1, 2, 3, and 4. 
 
Also see 
digio.writebit() (on page 7-64) 
digio.writeport() (on page 7-64)