MTSTesterDoc.tioga
Jean-Marc Frailong January 14, 1988 1:47:08 pm PST
MTSTester
DATools 7.0 — FOR INTERNAL XEROX USE ONLY
MTSTester
A PC-based functional chip/hybrid tester
Jean-Marc Frailong
© Copyright 1987 Xerox Corporation. All rights reserved.
Abstract: This package permits to generate and run test files for the MTS tester. Stimuli are captured from a transistor-level Rosemary simulation.
Created by: Jean-Marc Frailong
Maintained by: Jean-Marc Frailong <Frailong.pa>
Keywords: Dragon, VLSI, Hybrid, Test
XEROX   Xerox Corporation
    Palo Alto Research Center
    3333 Coyote Hill Road
    Palo Alto, California 94304

For Internal Xerox Use Only
1. The MTS Tester
1.1. Basic concepts
The MTS tester is a low-speed tester adequate for checking the functionality of chips or hybrids with large pin count. It is designed as a set of boards plugged in a PC/AT. Each board may handle 64 pins of stimulus/check data, but the current test setup uses only 60 pins per board. Testing speed depends on the number of boards used.
1.2. The MTS board: hardware
Body
1.3. The MTS board: software
Body
2. Generating an MTS vector file
Principles
An MTS vector file contains 2 major pieces of information: the mapping of DUT pins onto MTS boards and pins, and the test vectors themselves.
DUT pins description is obtained from a user-written file with suffix `mtsPins'. All comments in this file (Cedar-style) are ignored. The first line of the file is an identification that wil be saved in the MTS vector file. The remaining lines must have the following syntax:
<wire name> ":" <group><connector><pin in connector> ["PullUp"] ";" -- normal wire
<wire name> ":" "NC" ";" -- to be ignored by tester
where <wire name> is the name of the DUT wire, <group> is the number of the MTS board to which this wire is connected (0..9), <connector> is the connector id on this board (A, B or C), <pin in connector> is the number of the pin in that connector (1..20) and PullUp is an optional keyword indicating that this wire is connected to a pull-up on the test board. Note that there may be no space between <group>, <connector> and <pin in connector>. Wires specified as NC are ignored and are assumed to be unconnected to the tester. All wires in the public of the DUT must be specified in the pins file, including power supplies. For example:
Clock: 3B12;
nWR: 2C3 PullUp;
DataOut[3]: 0A20;
Spare[3]: NC;
MTS vector files are always generated from a Rosemary simulation, preferably at transistor level. They may either be derived from a RosemaryVector file, or be generated on the fly during the simulation.
Generation from a RosemaryVector file
The procedure MTSVector.FromRosemaryVectorFile converts a RosemaryVector file into an MTS vector file. This will be made available directly from a CD menu at a later date.
Generation during simulation
The procedures Create, WriteVectorFromPort and Close in MTSVector permit direct generation of an MTS vector file during simulation, using RosemaryVector to convert current simulation state into a DUT port.
3. Running a test on the MTS tester
Functionality
The MTS tester permits to run a test file in the following modes:
- single test: the test file is ran once, and stops at the first mismatch, indicating the cycle number (Rosemary Eval number) at which the error occured as well as the faulty bit(s).
- continuous test: the test file is ran in a loop until stopped by the user. Errors do not cause test to stop. The total number of succesfull passes is kept, as well as the length of the `best' pass (i.e. largest value of error cycle number). This mode is of interest to debug behaviour on the scope. The MTS tester generates a sync pulse that may be moved interactively by the user on the PC.
User interface
The user interface is still hazy. In a first step, test files will have to be manually onto the PC (using an XNS or NFS file server) and ran locally there. In a bright (and distant) future, it will be possible to control the tester from a Dorado.