Keithley 7707, User Manual

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CONFIG menu item
Figure 19 A shows the menu path to configure the digital I/O channels. After the appropriate slot is selected, work your way
through the menu to select the format for digital I/O data and set each channel as an input or output port. After setting a
channel as an output port, you will be prompted to enter a value that corresponds to the desired bit pattern.
The digital data format can set as ASCII (decimal), HEXadecimal, BINary, or OCTal. However, there is not enough room on
the front panel to display binary readings. Therefore, if you select the binary format, the hexadecimal format will instead be
used for front panel operation.
Example — The following CONFIG settings set Digital Output 1 for bit pattern 01001100. Also shown are the valid settings
range for each format type.
Selected format CONFIG menu Setting range
ASCII (decimal) DIGOUT1: 076 000 to 255
Hexadecimal DIGOUT1:0x04C 000 to 0FF
Octal DIGOUT1:0o114 000 to 377
VIEW menu item
Figure 19 B shows the menu path to view Model 7707 channels. After the appropriate slot is selected, close analog input
channels (1 through 10, 15, 16, and 17) and the digital input/output bit pattern values for channels 11, 12, 13 and 14 will scroll
across the display. The actual values for bit patterns will depend on the selected digital data format. The ASCII (decimal) data
format is the factory and *RST default.
The scrolling channel string is truncated by four dots (....) to indicate the end. The string of channels will scroll continuously
until it is stopped by pressing a front panel key.
Example — Assume a Model 7707 installed in slot, the hexadecimal digital data format has been selected and the following
channel string is scrolling for the VIEW item of the menu:
102, 117, 111:IN 0xAA, 112:IN 0xC1, 113:OUT 0xB2, 114:OUT 0xF0 ....
The above channel string indicates the following:
• Analog input channels 102 and 117 are closed. Channel 117 connects the input at channel 102 to the DMM.
• Channels 111 and 112 are set as input ports. Hexadecimal value AA for channel 111 indicates bit pattern 10101010
on the input port. Hexadecimal value C1 for channel 112 indicates bit pattern 11000001 on the input port.
• Channels 113 and 114 are set as input ports. Hexadecimal value B2 for channel 113 indicates bit pattern 10110010
is set for the output port. Hexadecimal value F0 for channel 114 indicates bit pattern 11110000 is set for the output
port.
NOTE The scrolling speed of the channel string is adjustable or can be paused. The key slows down
scrolling speed and the key speeds it up. The ENTER key pauses scrolling. Press ENTER a
second time to resume scrolling.
To exit from VIEW, press the EXIT key. Pressing an instrument setting key will also exit VIEW, but it will also perform the
operation associated with the key. For example, pressing
Ω
2 will exit VIEW, and select the
Ω
2 function.