P7001: Difference between revisions

Revision as of 08:53, 2 August 2019

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Digitizer for the 7704A oscilloscope

Produced from 1973 to 1981

Manuals

(All manuals in PDF format unless noted otherwise)

Manuals – Specifications – Links – Pictures

The Tektronix P7001 is a digitizer, processor, and memory for the 7704A oscilloscope. The P7001 can also be connected to an external computer which then is able to process the digitized signals. The complete system was called "Digital Processing Oscilloscope" or "DPO" for short and was presented to the public on 26 March 1973 at the IEEE Intercon in New York City.

The design of the P7001 assumes it will be part of a 7704A system, and that the 7704A will be displaying a steady trace. The vertical and horizonal plug-ins control the beam as they would in any 7000-series scope.

The P7001 periodically samples the horizontal and vertical signals simultaneously as they pass from the plug-ins to the vertical and horizontal amplifiers. This allows it to fill its memory with data points represented as coordinate pairs, (x1,y1), (x2,y2), (x3,y3), etc. It is not necessary that x2 be greater than x1, i.e. the samples can be taken out-of-order with respect to their equivalent time in the waveform.

Key Specifications

Resolution	10 bit (V), 9 bit (H)
Memory	four waveforms, 512 samples each (4K × 10 bit core, or multiple 1k × 10 bit or 2k × 10 bit RAM boards)
Sampling rate	150 kHz ±30 kHz
External interface	16 bit parallel, proprietary "CP bus" (dual 37-pin Sub-D connectors) interfacing with Tektronix CP-1100 or CP-4100 series controllers

Links

Catalog / Specs

Advertising

Internals

The signal coming from the acquisition unit enters a fast four-diode sample and hold circuit where it is sampled at 150 ksamples/sec. Each sample is digitized using a successive-approximation scheme. The analog to digital converter is made of several chips: a digital to analog converter, a comparator, and control logic.

The P7001 has its own power supply built into it, independent of the power supply in the acquisition unit of the 7704A. It has a backplane with an asynchronous bus and several cards that plug into that bus: sampler, analog to digital converter, memory, external digital interface, and display electronics. The P7001 was available with semiconductor memory or with magnetic core memory. Both types of memory were available through the whole production time of the P7001. In the first years the core memory module was cheaper and the default module. In later years the semiconductor memory module got cheaper and then this module was the default one. But the core memory module has one big adavantage: The memory content was preserved during a shutdown of the unit. This may have been the reason the core memory option remained available in the later years of P7001 production.

The bus is used for low speed signals. High speed signals are sent through coaxial cables that connect to the cards using Peltola connectors.

The Acquisition Unit of the 7704A, the P7001 Processor, and the Display Unit of the 7704A are connected by the Acquisition-Processor-Display (APD) Interface shown below.

Memory

Several types of memory configurations were available: 1k, 2k, 3k or 4k semiconductor memory and also 4k non-volatile core memory. All configurations were available through the whole lifecycle of the P7001. The memory serves to store the acquired waveforms and their associated scale factors. It also stores the computer output for display. Depending on the configuration the following storing capabilites are available:

Configuration	Waveforms	Readout Scale factors	Messages
1k with readout	1	1	3
1k no readout(*)	2	0	0
2k with readout	2	2	4
2k no readout(*)	4	0	0
3k	4	1	4
4k	4	4	12

* Removing the Readout-Interface card doubles the space for storing waveforms but eliminates the capability of displaying informations.

External Interfaces

Part Number	Description
021-0113-00	DPO to Data General Nova
021-0116-00	DPO to APD
021-0117-00	DPO to CP1100 (CP Bus)
021-0127-00	DPO to TEK31 calculator
021-0146-00	DPO to CAMAC
021-0175-00	DPO to 4010 Family
021-0206-00	DPO to GPIB

Pictures

Front panel
P7001 in 7704A
P7001 in 7704A

Internal

Top view
Front of backplane
main interface board (backplane)
Rear of backplane
Interunit connector
Interunit connector
Interunit connector
Switching power supply
front panel rear
extender boards

Keyboard overlay cards

blank card for user definable programs
Two examples of original overlay cards
Example of aftermarket overlay cards

External Interfaces (optional)

CPBus interface mounted
CP Bus Interface front
CP Bus Interface rear
GPIB Interface IO board
GPIB Interface IO board with shielding
GPIB Interface CPU board
Modern clone of the P7001 GPIB interface
Modern clone of the P7001 GPIB interface

Sample and Hold Card

Vertical sampling bridge
Horizontal sampling bridge
Sampling strobe generator
Sample and hold edge connector
Sample and hold transformers
Sample and hold transformer
Sample and hold rear

Core Memory (optional)

Address decoder
Core boards
Core memory
Core closeup
Core closeup
High Resolution view of partial core module

Semiconductor memory (optional)

2K semiconductor memory (aka "MOS")

ADC and Display

Front panel connections
ADC
ADC rear
Probe points on ADC
Display generator
Display generator rear
Z-axis and panel controller
Z-axis and panel controller rear
Readout interface

Hardware signal Averager (HSA)

HSA timing board. The HSA module (optional) performs signal averaging and can calculate a histogram.
HSA memory board.

Schematics

Block Diagram
Address map of a fully equipped P7001
Power supply schematic 1
Power supply schematic 2
APD Interconnect

Cofigurations

Example of Calculator based system (WP1100) in 1974
Example of Calculator based system (WP1100) in 1978
Example of Controller based system (WP1200) in 1973
Example of Controller based system (WP1200) in 1975

Workflow with connected Controller

With pressing a program-call button on the P7001...
.. the displayed signal is digitized...
...and transferred to the Controller...
...the Controller does some calculations...
...and transfers the result back to the P7001

X/Y Mode for external Controller

A connected computer has direct access to the Display Generator. This allows software-controlled live movements of the Beam.

Firmware (uploaded BIN files)

@@ Line 29: / Line 29: @@
 }}
-The '''Tektronix P7001''' is a digitizer, processor, and memory for the [[7704A]] oscilloscope. The P7001 can also be connected to an external computer which then is able to process the digitized signals. The complete system was called "Digital Processing Oscilloscope" or "DPO" for short and was presented to the public on 27 March 1973 at the IEEE Intercon in New York City.
+The '''Tektronix P7001''' is a digitizer, processor, and memory for the [[7704A]] oscilloscope. The P7001 can also be connected to an external computer which then is able to process the digitized signals. The complete system was called "Digital Processing Oscilloscope" or "DPO" for short and was presented to the public on 26 March 1973 at the IEEE Intercon in New York City.
 The design of the P7001 assumes it will be part of a 7704A system, and that the 7704A will be displaying a steady trace.
@@ Line 88: / Line 88: @@
 The Acquisition Unit of the 7704A, the P7001 Processor, and the Display Unit of the 7704A are connected by the
 Acquisition-Processor-Display (APD) Interface shown below.
+==Memory==
+Several types of memory configurations were available: 1k, 2k, 3k or 4k semiconductor memory and also 4k non-volatile core memory. All configurations were available through the whole lifecycle of the P7001. The memory serves to store the acquired waveforms and their associated scale factors. It also stores the computer output for display. Depending on the configuration the following storing capabilites are available:
+{| class="wikitable"
+|-
+! Configuration
+! Waveforms
+! Readout<br />Scale factors
+! Messages
+|-
+| 1k with readout
+| style="text-align:center;"|1
+| style="text-align:center;"|1
+| style="text-align:center;"|3
+|-
+| 1k no readout(*)
+| style="text-align:center;"|2
+| style="text-align:center;"|0
+| style="text-align:center;"|0
+|-
+| 2k with readout
+| style="text-align:center;"|2
+| style="text-align:center;"|2
+| style="text-align:center;"|4
+|-
+| 2k no readout(*)
+| style="text-align:center;"|4
+| style="text-align:center;"|0
+| style="text-align:center;"|0
+|-
+| 3k
+| style="text-align:center;"|4
+| style="text-align:center;"|1
+| style="text-align:center;"|4
+|-
+| 4k
+| style="text-align:center;"|4
+| style="text-align:center;"|4
+| style="text-align:center;"|12
+|}
+<nowiki>*</nowiki> Removing the Readout-Interface card doubles the space for storing waveforms but eliminates the capability of displaying informations.
 ==External Interfaces==
@@ Line 199: / Line 244: @@
 Tek_P7001_BlockDiagram.jpg|Block Diagram
+Tek_P7001_Addressmap.jpg|Address map of a fully equipped P7001
 P7001 ps1.jpg|Power supply schematic 1
 P7001 ps2.jpg|Power supply schematic 2