Table 3- 2: Mode Control Register 1 - Tektronix 2715 Service Manual

Control System Interface
2715 Spectrum Analyzer Service Manual
H Provides for the ability to place up to two markers on a displayed waveform
H Implement and display a B,C- -Save A waveform
H Display readout information on the screen
H Provide up to 28 Kbytes of nonvolatile storage area
H Provide two different waveform acquisition modes: Max Peak and Min/Max
H Provide a Max Hold function
The following sections show the bit maps for each of the control registers on the
Display Storage board.
Mode Control Register 1. Mode Control Register 1 is located in I/O space, at
location 0x0FA00. Mode Control Register 1 is a read/write register. Table 3- -2
describes the Mode Control Register.

Table 3- 2: Mode Control Register 1

Bit
Number Mnemonic
7 DSON_L
6 DISP- - A_L
5 MAXHLD_L
4 PEAKDIS_L
3 HLF/FLL_L
2 ACQ_ON
1 RDZEN
0 DS_PROTECT
DSON_L. Enables the Display Storage board to display the digitized waveforms
when low. When this signal is high, the analog trace is drawn on the CRT.
DISP- -A_L. Invokes the B,C- -Save A display on the CRT when low.
MAXHLD_L. Invokes the Max Hold algorithm for A and B waveforms when
low. In this mode a given bin will only be updated when the new vertical data is
greater than the stored vertical data.
Activity
Level Description
Low Display Storage On
Low Enables B,C- - Save A Display
Low Enables max hold function
Low Enables max peak function
High Selects location of B,C- - Save A display
High Enables the acquisition system
High Not used
High Not used
Theory of Operation
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