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Tester 297



Tester 297

Tester 297E

Right:Tester 297 being used in the street, A blue hard hat should always be worn.
Left: Top view of tester

Typical Use after RAM data loss

The Payphone is opened and the tester 297 plugged into the 9 pin socket
if the tester does not display anything immediately the hook switch of FOC button should be pressed
then the LCD displays ..

Then to write the fixed information press the [enter]

enter
The ENT full stop should appear
Enter

Then press the [PCO] key or [RCB0] or [RCB1] or [RCB2] if your payphone is a renters rather than public
PCO


Both PCO/RCB full stop and ENT full stop should show

enter pco rcb


 the press [enter]  again

the tester writes 172 characters in about 3.164 seconds at 1200 baud data to the payphone RAM

pco write to ct24

Writing form tester to payphone 8A

write 0D

The Gap between each 10 bit character is around 10 mili seconds...

inter packet gap

Which means characters are sent round every 18.5 milli seconds or at 15.4 Hz

char sent every 18 ms


The following data is the observed if its an 8 bit byte with no parity..

8A 8A 8A 43 8 C4 8A 8A 8A 8A 8A 8F 0D 8F 8F 8F 8F 83 8F 8F 8F 8F 8F 8F 8F 8F 7 8F 0D 8F 8F 85 85 89 2 86 8F 8F 8F 8F 8F 8C 8F 83 8F 8F 8F 8F 8F 8F 8F 8A 0D 7 8F 0E 80 80 80 83 80 80 80 8A 8 80 80 8A 8A 85 80 8A 8A 8 8A 8A 86 2 4 1 80 89 85 4 1 80 80 2 86 7 80 89 85 86 7 2 83 2 85 1 1 83 89 8 1 1 83 89 86 7 80 1 89 85 4 1 80 2 89 85 4 1 80 4 89 85 4 1 80 85 89 85 4 1 80 8 89 85 4 1 80 80 80 2 8A 8 80 1 83 2 86 7 80 4 83 2 86 7 80 7 83 2 86 7 80 8A 83 2 86 7 83 8 7F

With 7 data bits and odd parity it look like this..


0A 0A 0A 43 8 44 0A 0A 0A 0A 0A 0F 0D 0F 0F 0F 0F 3 0F 0F 0F 0F 0F 0F 0F 0F 7 0F 0D 0F 0F 5 5 9 2 6 0F 0F 0F 0F 0F 0C 0F 3 0F 0F 0F 0F 0F 0F 0F 0A 0D 7 0F 0E 0 0 0 3 0 0 0 0A 8 0 0 0A 0A 5 0 0A 0A 8 0A 0A 6 2 4 1 0 9 5 4 1 0 0 2 6 7 0 9 5 6 7 2 3 2 5 1 1 3 9 8 1 1 3 9 6 7 0 1 9 5 4 1 0 2 9 5 4 1 0 4 9 5 4 1 0 5 9 5 4 1 0 8 9 5 4 1 0 0 0 2 0A 8 0 1 3 2 6 7 0 4 3 2 6 7 0 7 3 2 6 7 0 0A 3 2 6 7 3 8 7F


The last 7F I believe is from the payphone to the tester to say "rxed ok"

then [OK] and [ENT] dot appears to let us know write went ok


OK



Then to program the number the phone dials to report status and errors


press [enter] [main] 0123456798[enter]


The inter gap between the first and second character is longer than the others are around 22ms, the rest are closer to 10 ms apart including the 7F Ack from the payphone at the end

bit pattern


1st inter char gap is bigger


The following 7 bit chars are observed

00 0A 01 02 03 04 05 06 07 08 09 0A 00 00 000 00 7F

Now we will write 222 to the same register (Main)


ENTER MAIN 222 ENTER

This is sent by the tester sending a 00 the 16 characters containing the phone number, in this case 222 then zeros then the payphone acknowledge safe receipt with 7F

write main 222 write

00 02 02 02 00 00 00 00 00 00 00 00 00 00 00 00 00 7F 


enter main 222
Note above the [ENT] and [ok] decimal points confirm the write was successful 


to check the number is now in payphone 


[read] [main]

read main
[read]

read main 222

Above the payphone responds with a 02 about 12 mS after the 01 is sent to it.

The tester 297 takes about 30mS before returning an Ack(7f), perhaps this is a variable length packet

delay before ACK
Read Main 222

Note the [RD] and [OK] decimal points are lit 


in 7 bit we get
01 02 02 02 00 00 00 00 00 00 00 00 00 00 00 00 00 7F

now to program the payphone ID or CTI (Coin Telephone Ident) 


[enter]
ENTER
 [CTI] 
CTI Coin Telephone ID

ENT CTI


111

one
one
one



enter cti 111

 [enter]

ENTER



pulse train entet cti 111 enter

08 01 01 01 00 00 00 00 00 00 00 00 00 00 00 00 00 7F



enter cti 111 enter


to check

[read][CTI] [read]


09 01 01 01 00 00 00 00 00 00 00 00 00 00 00 00 00 7F


The Tester 297 is a handheld programmer for the GPT/Plessy type payphones,but was originally for programming the Coin Telephone 22B

In December 2019 PE says "It was developed by Autelca, Gumligen, Berne (German Speaking Switzerland!) for the Blue Payphone 1 - large stainless steel coin box, with RED LED display showing Minimum Fee, and money remaining etc.  This was known as the "Coin Telephone 22A" and was used in London Railway Termini, and a few airports.  The phone accepted UK Decimal coins: 2p  10p and 50p (if I remember correctly).  Minimum call fee was I think 8p.  All these settings were communicated to the telephone from the memory chip in the Tester 297.

When you plugged in a Tester, there was an initiation data exchange.  I think the Tester sent ^E (Hex 05) and the payphone responded with a code to say what model it was, what the latest tariff was in its memory etc. 

The Coin Telephone 22B came along soon after from Autelca, which was in the same type of metal case, and worked with the Tester 297.  The payphone had grey numerals (Liquid Crystal Display) to  advise the customer.  More widely used than the 22A.

Then the Landis & Gyr Cardphone 1A came along, and was designed to work with the Tester 297.  The Cardphone 1C (with colouring of front case and back case reversed when compared with a 1A) also used the Tester 297.  There were several thousand of those in service.

Now, we are coming to the Plessey Payphones.  The Blue Payphone 2 (Coin Telephone 24 or Payphone 600)  had the phone mechanism in its upper box, and the lower box was the cash container.  The Plessey payphones were generally designed to work with the Tester 297.  There was then the Payphone 500, similar technically, but with less armouring of the case,  Intended to be used inside buildings where supervised.  This also used the Tester 297.   By now, the Tester 297 could send ^E (Hex 05) or ^F (Hex 06) to say if it had enough tariff memory on board to enable 0800 and other free codes to be called with no money in the coin box.  I assume all but the CT 22A were updated to match the later standard.

There was then a cheapened version of the Payphone 600, the coin Telephone 34A, known as "The Low Take".  Not sure how that was programmed.

Finally, there were "Table Top" Payphones 100 from AGI in the UK, which had a new memory chip put in (instead of using Tester 297) and the Payphone 200, a wall-mounted version of the 100 design.  Plessey made a Payphone 300, being a smaller version of the 500, and that did not need a Tester 297
."

It contains 2 PCBs, the first has the processor, Eprom, Ram and interface circuitry

 PCB markov               ov            +              +       o/p i/p
 pcb number 21 20 19 18 17 16
 cable colour white brown yellow pink grey green
9 pin plug 3 8 5 7 4 9
       

Tester 297 Pinout




Tester 297 pinout










It has the same CMOS 8 bit  CDP 1802  processor as the Payphone, running with a 2Mhz crystal. 
The CDP1802 family of CMOS microprocessors are 8-bit register oriented central processing units (CPUs) designed
for use as general purpose computing or control elements in a wide range of stored program systems or products.
The CDP1802 types include all of the circuits required for fetching, interpreting, and executing instructions which have
been stored in standard types of memories. Extensive input/output (I/O) control features are also provided to facilitate system design.


At the bottom left of the processor board is a ZIF socket, with nothing in it.
At the top centre is an empty Blue 20 pin DIL socket marked SK1

The back of the micro board has a number of "mods"

At the very top of the board is a strip of 15 contacts that connect with the Display and Keypad PCB


The Back of the this board is fairly plain, the back of the switch contacts and LCD dirver ship can be seen.


The µPD7225 is a software-programmable LCD (Liquid Crystal Display) controller/driver.  The µPD7225 can be
serially interfaced with the CPU in a microcomputer and can directly drive 2, 3, or 4-time division LCD.  The µPD7225
contains a segment decoder which can generate specific segment patterns.  In addition, the µPD7225 can be used to
control on/off (blinking) operation of a display.





Subpages (1): Tester 297 - Protocol
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