Programmable signature analyser

Hewlett-Packard has announced a signature analyser (the 5006A) that offers full opt ion programmabil i ty on the Hewlett-Packard interface loop (H P-IL).

Composite signature and signa- ture memory are included and, according to the company, can save the user t ime when troubleshooting digital circuits by hand. Composite signature sums individual node signatures and t ime is saved in verifying the correct operation of an IC, bus or other convenient block of nodes by making one comparison of the composite signature to the document. A good composite signature verifies that all individual nodes checked are good. A bad composite signature indicates that one or more of the individual signatures is bad.

SIGNATURE M E M O R Y STACK

Time is also saved and operator errors are reduced when gathering or comparing signatures using the new signature memory stack. This eliminates hold ingthe probe on the node, reading the display and comparing it to the documentat ion for each measurement. All the signatures can be entered on an IC, for example, by simply pressing the probe button when moving from pin to pin. Later, the signatures can be recalled to the display by pressing the probe button in the recall mode. All the pins on a device can then be probed wi thout reference to the documentation. Only if the composite signature does not match, does the user need to review the individual signatures to find the faulty pins.

Each t ime the probe button is pushed, a signature is entered into the memory and added to the composite signature. If a new signature is writ ten over an old one by pressing the probe button, the composite signature is updated in the edit mode. Signatures can be reviewed by simply pressing the

recall button and rolling the stack with the probe button.

In addit ion to HP-IL programma- bility, the new signature memory and new composite signature function, the HP 5006A offers a number of advantages over the original H P 5004A signature analyser.

• the 25 MHz clock rate extends the signature-measurement capa- bi l i ty to higher-performance digital circuits,

• CMOS logic thresholds, in addit ion to standard TTL, offer a more thorough coverage of digital products,

• displays and unstable light can detect intermittent faults and unstable signatures,

• HP-IB programmabil i ty is available as an option allowing the addit ion of the signature- measurement function to auto- matic test systems,

• two modes of the signature measurement (normal and quality) forsimplified component- level fault-isolation are com- patible with the HP 5005A/B signature-multimeter products.

According to the company, the use of small, dedicated test stations is now feasible with the interface loop with a concomitant improvement in productivi ty and saving of time. Instrumentation is now claimed to be feasible in smaller operations where previously it was not cost effective.

LOG IC- PROB E STATUS

Logic-probe status is now available at the programmable interface. The HP 5006A can therefore offer greater test coverage with a controller that has more infor- mation for guided backtrace algorithms. For example, the controller can report the difference between a stuck logic-high or logic- low signal and a signal that is always logic-high or logic-low at clock time.

In addit ion simple logic-probe troubleshooting can be automated. The controller can read logic-high, high impedance state, logic-low and active data from the probe through the HP 5006A.

The H P 5006A is completely pro- grammable from the HP-ILor HP-IB interface. With a single special command, the complete front- panel status can be sent to the controller. The control ler can do the reverse - - control (reconfigure) the front panel with one command. According to Hewlett-Packard, these features make test procedures faster to generate and run. (Hewlett-Packard Ltd, King Street Lane, Winnersh, Wokingham, Berks, RGll SAR, UK. Te1:0734 784744) []

POS terminal

Mitsubishi has launched its T-700 programmable point-of-sale (POS) terminal.

The user can program all POS functions in the T-700, including data display, tax and discount computation rules, receipt and journal printouts and summary reports prepared by the terminal.

Functions are adaptable to store size and condit ions by use of optional accessories. A basic terminal can be configured as a slave, master or grand master. Each master terminal can control 15 slave terminals, and a grand master can control 15 master terminals with their loops of up to 15 slaves, or a total of up to 240 terminals.

In addit ion to normal terminal functions, the master terminal includes extended memory plus data logging and program storage on a mini f loppy disc. A grand master includes extended memory, two mini f loppy disc drives for total system logging by line item, and a CRT display for data monitoring, program revision and pricing ease. (Mitsubishi Electric Corporation, 2-3 Marunouchi 2-chome, Chiyoda- ku, Tokyo, Japan. Tel: 2182171, Tx: 24532) []

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