WO1989011134A1

WO1989011134A1 - Electronic computing and storage system for franking machines

Info

Publication number: WO1989011134A1
Application number: PCT/CH1989/000081
Authority: WO
Inventors: Hans-Peter Liechti; Anton Aebi; Marc Von Weissenfluh
Original assignee: Ascom Hasler Ag
Priority date: 1988-05-09
Filing date: 1989-05-05
Publication date: 1989-11-16

Abstract

A computing and storage system (40) is a sealed unit comprising an electronic microcontroller (42) which co-operates via a bus (50) with four mutually independent stores. The stores are a working store (44), a program store (45) and two non-transient mailing charge stores (46, 47) of different technological types. Also provided are two mutually independent monitoring units (53, 54) which monitor the performance of the microcontroller (42), and a postal lock (60) which locks and prevents access to the computing and storage system (40). In each franking operation, the processor (42) obtains the necessary data via its input/output (43) and codes the corresponding mailing charge together with a series of other data serially in the two stores (44, 46, 47). After each coding operation in one of the mailing charge stores (46, 47), the microprocessor (42) checks whether the final coded line agrees with the final coded line of one of the other stores. Immediately a discrepancy between the data or an error in the assembly is detected, the computing and storage system (40) is blocked, the contents of the mailing charge stores (46, 47) remaining intact.

Description

Electronic arithmetic and storage unit for franking machines

The invention relates to an arithmetic and storage unit for franking machines for storing and debiting franking amounts in accordance with the preamble of claim 1 and its operating method.

Franking machines and their tasks are generally known, e.g. from R. Grünig et al: "The Hasler Mailmaster F 300 MPM Franking Machines" in Hasler-Revue 16 (1983) 4, 90-94.

Fig. 1 shows the block diagram of this franking machine, which is composed of two main assemblies. The first main assembly is the so-called drive unit 11, to which the mail item 12, in particular letters to be franked, is fed. The drive unit 11 comprises a switch 13 for detecting and a notor-operated feeder 14 for transporting the letters and a clutch 15 for driving the units of the second main assembly which are still to be discussed. The units mentioned are contained in a basic chassis, which also contains the feed unit 16 for the overall franking machine, a first processor 17 with an associated data memory 18 and a printer 19. The latter units are used primarily for the accounting of the franking machine operator, e.g. when different departments of a company use the same franking machine. The drive unit 11 is unproblematic because it is not subject to any postal regulations.

It is different with the second main assembly, the so-called franking unit 20. This is detachably connected to the drive unit 11 and is subject to very strict postal regulations, since with it it is impossible to enforce very large amounts of money, for example 100,000 currency units per year, for example Swiss Franconia. The franking machine 20 u contains as the heart a second processor 21 with an associated memory 22, to which a keyboard 23 as input means and an electronic display 24 are assigned. Further inputs and outputs can take place via electrical feed lines D and P from external units, for example a postal scale with an assigned port computer. The electronic assemblies listed here are now assigned purely mechanical assemblies via an electromechanical interface 25. These are the so-called rotor 26, a cam mechanism 27, an inking unit 28, an arithmetic unit 29 and two. Counters 30, 31.

Before a letter can be stamped and franked, the required postage amount is set in the rotor 26 via the interface 25. The rotor 26 is then driven via the clutch 15 and the cam mechanism 27 in such a way that it executes a single, complete revolution, wherein it is colored by the inking unit 28 and the color is stamped on the letter running through synchronously. Parallel to this, the arithmetic unit 29 is forcibly actuated via mechanical coupling elements and a new counter reading is formed in the counters 30, 31. The counter 30 counts up as a charge counter, the counter 31 counts down as a default counter.

The. Franking unit 20 forms a closed unit which can only be operated in cooperation with the drive unit 11 and whose counters 30, 31 are only accessible via a so-called mail lock. This is e.g. a mechanical security lock, the key of which is kept by the approving post office, so that only an authorized person, e.g. a counter clerk at the local post office who can reset counters.

The counters 30, 31 are designed as robust, mechanical roller counters, which can be read off directly via a viewing window and whose count value or their counter reading at Switching off the franking machine is automatically retained without any measures. The counters thus form visually readable, fail-safe memories for accumulated amounts of money that can be changed manually, for example resettable to zero.

These advantages of the mechanical counters 30, 31 are offset by major disadvantages. These are:

- Compared to the common electronics, the mechanical counters belong to an outdated technology.

- The mechanical counters work relatively slowly and thus limit the working speed of the franking machine.

- Working together with electronic assemblies and additional units is complicated.

- The space requirement is relatively large and inflexible.

The object of the invention is therefore to replace the mechanical counters or arithmetic units in franking machines by electronic storage and arithmetic units. Of course, all existing postal requirements and regulations for franking machines must be observed. Above all, this is absolute protection against abuse and fraud, e.g. by franking letters without paying the postage. This also means that you can work according to the credit or default method. In the credit process, subsequent payment of the amounts of money accumulated in the storage units, e.g. per month. In the default procedure, however, the storage units are set to any amounts of money to be paid in advance. Postage can then be paid until the remaining amount has been used up.

The solution to the task under consideration of all secondary conditions is given by the independent claims. The dependent claims reflect embodiments of the invention. The specified solution enables electronic franking machines to be built up to a greater extent. This clears the way for connecting the franking machines to other electronic devices such as remote reading devices, remote setting devices for the targeted storage of specified amounts of money, data evaluation units, fully automatic inserting and franking lines, etc.

The solution is based on the primary idea of redundantly equipping the electronic storage unit with memories in such a way that the security against a total failure is drastically increased. For this purpose, two or more semiconductor memories of different technical designs are provided, which are operated in parallel under constant mutual and other control. This significantly reduces the likelihood of all memory failing at the same time due to the same cause, e.g. due to faulty voltage levels.

In the following the invention is based on three more

Figures, for example, described in more detail. Show it:

Fig. 1 - block diagram of a known franking machine as

PRIOR ART Fig. 2 - block diagram of an arithmetic and storage unit Fig. 3 - example of the memory organization Fig. 4 - flow diagram for the operational sequence.

Fig. 1 was discussed as prior art in the introduction. The new electronic arithmetic and storage unit 40 to be described below essentially replaces the arithmetic unit 29 as well as the counters 30 and 31, the outer shape of the franking unit 20 being largely retained and the electromechanical interface, comparable to the one described (25), only is only necessary for the franking setting in the rotor 26. The said second processor 21 and the memory 22 are for practical reasons in the computing and Storage unit 40 included.

2 shows a block diagram of the arithmetic and storage unit 40 according to the invention. This comprises a microcontroller 42, four memories 44 to 47 constructed independently of one another, a bus line 50, two separate monitoring units 53, 54 and two gatekeeper units 56, 57 a mail lock 60 of the type described.

D: First: - Memory 44 is a RAM memory (random access memory) and serves as a general working memory of the microcontroller 42 and as a buffer for smaller amounts of money that have been used up as postage or as franking amounts.

The second memory 45 is an EPROM memory (erasable programmable read only memory), a ROM memory (read only memory) or, less sensibly, a PROM memory (programmable read only memory), the selection being made essentially according to practical aspects. This memory 45 contains all the programs for operating the microcontroller 42 and thus forms the program memory of the arithmetic and storage unit 40.

The third memory 46 is in turn a RAM memory which is fed by a buffer battery 39 in such a way that its data content is retained even in the absence of the actual supply voltage.

Finally, the fourth memory 47 is an EEPROM memory (electrically erasable programmable read only memory). This is a non-volatile semiconductor memory to which data can be input in a limited number of memory cycles, e.g. 10,000 cycles at most.

The third 46 and in parallel the fourth 47 and the first memory 44 each serve to store and store one important data for the respective postal administration. This will be discussed in more detail later.

The four memories 44 to 47 are connected to the microcontroller 42 via the bus line 50. This bus line is formed in a manner known per se as a bundle of lines for data exchange. The microcontroller 42 is further connected via inputs / outputs 43 to other units, in particular the input keyboard 23 and the electronic display 24 (FIG. 1), and via connections 66, 67 to the gatekeeper units 5-5 and 57 respectively.

The microcontroller 42 operates in the usual way on the basis of the programs contained in the program memory 45. He generally uses the first memory 44 as a working memory. In its function as a replacement for the arithmetic unit 29, the microcontroller 42 works in a special way with the memories 44, 46 and 47. The gatekeeper units 56, 57 are used for special control and allow access to the memories 46 and 47 only after prior registration. They also ensure that any further access is prevented after each access. These functions are essentially independent of the microcontroller 42 and its program contained in the memory 45.

The structure of the gatekeeper units 56, 57 is e.g. in a simple design from a plurality of AND gates operated in parallel, which are inserted into the individual lines of the bus line 50 and can thus block these lines. There is also a separate controller for controlling the gates, which receives its instructions via connections 66 and 67, respectively.

As a further protective measure, the functionality of the microcontroller 42 is continuously monitored by units 53 and 54, which are also independent of this (42). The monitoring unit 53 monitors in particular the supply voltage (power fall) and work interruptions (interrupts) and emits error signals as soon as an error occurs is determined, ie if, for example, the supply voltage breaks down because the franking machine has been switched off (at the possibly wrong time). The monitoring circuit 54 takes effect when all other safety measures are unsuccessful. It checks whether a signal occurs in the signal flow of the microcontroller 42 at very short intervals, for example every 8 ms. If this is not the case, then it immediately blocks the microcontroller 42, ie after, for example, 10 ms. The unit 54 thus forms a kind of emergency brake for the arithmetic and storage unit 40.

The computing and storage unit 40 is mechanically encapsulated from the outside and is only accessible after the aforementioned mail lock 60 has been actuated. This lock 60 is equipped with a further backup battery 61 and with a magnetic switch 62. This switch 62 must first be activated by the microcontroller 42 after each start-up of the franking machine, before the other functions of the machine can be started.

3 schematically shows the organization of the memories 44 and 46. For each franking process, these memories each provide a memory line (page) and for each franking process a data record 69 created by the microcontroller 42 is successively stored in one line at a time. Each data record 69 comprises several data in the same order, in particular a consecutive number 70 as a counter for the total number of frankings, the date 71, a status display 72 about the machine status, for example "freshly switched on", a fee counter 73 (total value of all postage and / or Franking amounts) to indicate the integral franking amount of all previous frankings, a default count 74 for indicating the remaining amount of the last amount entered by the post office, a CRC amount 75 and possibly further details such as an operator xamen. Under the name CRC-Sumne (cyclic redundancy check) an error check value is too understand, which provides more information than a parity bit about all possible errors or the absence of errors in the respective memory line. The calculation of the CRC sum is carried out, for example, with the aid of a standardized 16th degree test polynomial from the bytes of the respective line in accordance with standardized procedural information from the international standardization body CCITT, Geneva.

Due to the line-by-line structure of the memories 44 and 46, an archive-like overview over a longer period of time and the frankings made during this time are successively created in these. The specified time period is given by the number of franking processes that are to be stored as a maximum and by the franking rate. As soon as the maximum number of lines provided in the memories 46, 47 are filled, further lines are formed by overwriting the oldest lines. This creates a kind of ring structure of the memory. When overwriting each line, it is always checked whether the respective line can still be used or whether it is possibly defective. In the latter case, this line is marked as defective and skipped. The maximum number of lines provided is in the memory 46 e.g. 100.

The memory 47 as an EEPROM memory is limited in the number of write cycles. It is therefore organized in such a way that a line is not saved for every franking process, but only for special processes. For this purpose, the memory 47 interacts with the memory 44 in such a way that the data records 69 assigned to the franking operations are temporarily stored in the memory 44 in the manner described until a predetermined amount for postage or a predetermined amount, for example 20 currency units (dollar, Swiss franc, ..) has accumulated. As soon as this amount is reached or exceeded, the last data record 69 is transferred to a line provided in the memory 47 and is thus stored in a non-volatile manner. A corresponding transfer or backup also takes place, when the monitoring unit 53 announces an imminent failure of the supply voltage (power fail) of the volatile memory 44, ie for example each time the franking machine is switched off.

The secure, relatively long-term storage of the franking amounts thus takes place in parallel in the two non-volatile memories 46 and 47. These are therefore referred to below as the first and second franking amount memories.

The arithmetic and storage unit 40 now works as follows (FIG. 4):

As soon as a letter is to be franked, a corresponding message is made via the inputs / outputs 43 and the necessary postage amount is entered, e.g. 50 centimes and a start order. The microcontroller 42 then creates a new data record 69 in accordance with the program in the program memory 45 and in cooperation with the working memory 44. This means that the microcontroller 42 forms the next sequential number 70, indicates the status 71, calculates the new fee 73 and default count 74 and forms the CRC sum 75. As soon as the data record 69 has been completed and stored in the working memory 44, the microcontroller 42 logs on to the first gatekeeper unit 56 via the connection 66. This normally releases the bus line 50 to the first franking amount memory 46 and the microcontroller 42 also writes the said data record into the memory 46. The microcontroller 42 then reads the content of the line just occupied, calculates the CRC sum 75 again for checking purposes, and compares the result with the data record 69 still stored in the working memory 44. The gatekeeper unit 56 then blocks the bus line 50 again.

If the desired correspondence is given in all points, the. Microcontroller 42 now examines whether one in the working memory 44 with the data record 69 mentioned Amount has been reached that requires storage in the second franking amount memory 47. If this is not the case, then the microcontroller 42 ends its work. If, on the other hand, the said amount has been reached or exceeded, the microcontroller 42 logs on to the second porter unit 57 via the connection 67. This then releases the bus line 50 to the second franking amount memory 47, the microcontroller 42 now transfers the data record 69 from the working memory 44 to the second franking amount memory 47, reads the line described again and compares the data with the corresponding data record 69 in the first franking memory 46. The gatekeeper unit 57 then blocks the bus line 50 again.

The procedures described ensure in each case that each franking amount is stored in parallel in two memories, temporarily in the working memory 44 and permanently in the first franking amount memory 46 and in larger steps in the second franking amount memory 47. By comparing the contents of the latest memory lines in each case This ensures that the memory contents are the same and that no errors creep in. The use of different algorithms for the various storage processes, the formation of the CRC sums 75 and the function of the gatekeeper units 56, 57 help here. The other independent monitoring units 53, 54 also help.

If there are discrepancies somewhere, the computing and storage unit 40 recognizes this very quickly and emits a warning message. If there is a serious discrepancy, the arithmetic and storage unit 40 is blocked.

Overall, this results in an electronic storage device corresponding to the previous mechanical counters 30, 31 and secured against counterfeiting, misuse, etc. In addition to the advantages of the electronic structure, this has the significant further advantage that it is not only indicates two meter readings as before, but contains considerably more information stored. In particular, due to the line-by-line structure of the franking amount memories 46, 47, in the event of a check, all operations and frankings can be traced back precisely over a considerable period of time. In the event of misuse, this provides more information about the type and scope than before. In the case of normal errors, conclusions can be drawn about their causes. The parallel storage of the data in two independent, non-volatile franking amount stores provides security against collective failure, the use of two different types of storage increasing this security.

The arithmetic and storage unit 40 described can be varied in many ways without departing from the actual inventive concept. The following variants are therefore mentioned:

Instead of the two non-volatile franking amount memories 46, 47, three such memories are used, into which the respective franking amounts are written independently of one another.

The calculation and writing of the franking amounts into the different franking amount memories takes place in a changed order based on the same or different algorithms.

There are an identical or a different number of memory lines (pages) in the different franking amount memories 46, 47.

The information content of the memory lines can be expanded compared to the data described and reduced to a limited extent. eg by omitting the date. The consecutive numbering can correspond to the absolute number of frankings or another criterion, for example the number of registration cycles. The structure of the microcontroller 42 can be of any design. In particular, a hard-wired logic unit can also be used, which jointly replaces the program memory 45 and the microcontroller 42.

For the storage and reading procedures, above all practical aspects are decisive, which depend on the selected technology of the device.

The. the memory contents can be read visually via the display 24. Should the entire memory content be checked, e.g. in the event of a malfunction, the contents of the memory can be printed out using a printer belonging to the post office.

The gatekeeper units 56, 57 can e.g. be omitted for price reasons.

In particular, the program memory 45 can be designed as a ROM, PROM or EPROM memory or as another read-only memory.

Overall, the electronic arithmetic and storage unit 40 forms an inexpensive unit which fully meets the tough requirements and which offers the advantages of flexibility, the enormously increased storage capacity and the ability to connect to almost any external peripheral device compared to conventional arithmetic and storage units. The electronic arithmetic and storage unit 40 thus forms a unit that brings real progress in the field of franking machines.

Claims

1. Computing and storage unit (40) for determining and storing franking amounts in a franking machine, the computing and storage unit (40) being mechanically encapsulated and accessible only via a mail lock (60), the respective franking amounts being visually readable, and being in all cases where the permitting

Pσstverwaltung or the operator of the franking machine could suffer a financial loss, the computing and

Storage unit (40) blocked so that the respective stored franking amounts are legibly retained, marked

- by an electronic microcontroller (42),

by a program memory (45) which contains a program for controlling the microcontroller (42) and for creating a data record (69) for each franking operation,

by a working memory (44) for storing any intermediate results of the microcontroller (42) and each data record,

by a first non-volatile franking amount memory (46), which is designed for immediate line-by-line storage of each data record created by the microcontroller (42),

by a second non-volatile franking amount memory (47), which is designed for line-by-line storage of selected data records contained in the working memory (44),

- By a bus line (50) for connecting the microcontroller (42) and the memory (44, 45, 46, 47) and

- Through inputs ^• 43 (43) for connecting the .Microcontroller (42) with input and output means (23, 24).

2. Computing and storage unit according to claim 1, characterized in that - that the program memory (45) is a λ'ur read memory (read only memory),

- that the main memory (44) is a read / write memory (rando access memory),

- that the first franking amount memory (46) is a volatile read / write memory (random access memory), which is secured by a buffer battery against loss of the data stored in it,

- That the second franking amount memory (47) is a non-volatile read / write memory (electricall erasable programmable read only memory), and

- That the bus line (50) is designed as a plurality of connecting lines between the microcontroller (42) and the memories (44, 45, 46, 47).

3. Computing and storage unit according to claim 1, characterized in that in the first franking amount memory (46) a first and in the second franking amount memory (47) a second number of lines is provided for the successive and repeated storage of a data record (69).

4. Arithmetic and storage unit according to claim 1, characterized in that each data set (69) at least one consecutive number (70), a status display (72), a fee count (73), a default count (74) and one CRC sum (75) (cyclic redundancy check).

5. Computing and storage unit according to claim 4, characterized in that each data record (69) additionally comprises a date (71).

6. Computing and storage unit according to claim 1, characterized by a first (56) and a second gatekeeper unit (57) which are inserted into the bus line (50 ⁾ and the first (46) or are assigned to the second franking amount memory ⁽ 47) and which only allow the microcontroller (42) to interact with the assigned franking amount memory (46, 47) only after prior notification.

7. Computing and storage unit according to claim 1, characterized by a first monitoring unit (54) for monitoring the functionality of the microcontroller (42), which is constructed independently of the microcontroller (42) and the memories (44, 45, 46, 47) , and which blocks the arithmetic and storage unit (40) if the microcontroller (42) is not functioning properly.

8. Computing and storage unit according to claim 1, characterized by a second monitoring unit (53) for monitoring the supply voltage and operational interruptions, which is constructed independently of the microcontroller (42) and the memories (44, 45, 46, 47), and which emits an assigned signal to the microcontroller (42) before the supply voltage collapses.

9. Computing and storage unit according to claim 1, characterized in that the mail lock (60) has a backup battery (61) and a magnetic switch (62).

10. The method for operating the arithmetic and storage unit according to claim 1, characterized in that each data record (69) created by the microcontroller (42) is immediately stored in the first franking amount memory (46) and temporarily stored in working memory (44) in that a constant check is carried out to determine whether an amount amount has accumulated in the working memory (44) that is greater than or equal to a predetermined money amount, and l f. that as soon as this is the case, the last data record (69) stored in the working memory (44) is transferred to the second franking amount memory (47).