JP2550434B2 - Drive machine number setting circuit - Google Patents

Description

Detailed Description of the Invention 【Overview】

Regarding the drive unit number setting circuit of the interface circuit in which multiple drive units are connected to the adapter unit of the device via the mother board, the unit number is automatically set by connecting the drive unit connector to the common motherboard divided into multiple sheets. For the purpose of being able to do so, connect the specified number of connector pins for connecting the motherboard to 0,1 to set the machine number lower bit, and connect the specific pin of the connector pin for connecting the drive to different 0,1 for each motherboard. Then, set the machine number upper bit, and configure it so that different machine number settings can be automatically set for the drive by connecting the drive connector to each motherboard.

[Industrial applications]

The present invention relates to a drive device number setting circuit of an interface circuit in which a plurality of drive units are connected to an adapter unit of a device such as a magnetic disk device via a motherboard. In a magnetic disk device, for example, which can control a plurality of drive units from one adapter unit, a motherboard is connected to a tag bus line of the adapter unit, and a plurality of drive units are connected to the motherboard by connectors. The machine number of the part is set by connecting a predetermined number of connect pins with the drive part to 0, 1 on the motherboard. Therefore, by simply connecting the drive unit to the motherboard, the drive unit automatically recognizes its own set machine number from the connection status of the specified connector pins, and responds to the selection command specifying the machine number from the adapter unit. Only the specific drive unit with the matched number receives control. However, since the printed circuit board becomes too large with one motherboard, the motherboard will be divided into two. In this case, a connection pattern with a connector pin with a different machine number setting is required for each motherboard.
You need two types of motherboards. Therefore, it is desired that the motherboard can be used in common even if it is divided into two or more.

[Prior art]

FIG. 4 shows a conventional magnetic disk device interface circuit. A tag bus signal by a cable (tag bus line) 22 drawn from a magnetic disk device adapter section 14 (hereinafter simply referred to as "adapter section") is , A plurality of magnetic disk device drives (hereinafter simply referred to as “drive units”) 10, and one adapter unit 14 to a plurality of drive units 10, for example, eight drive units 10 with machine numbers # 0 to # 7. To be able to control. In this case, since a plurality of drive units 10 are connected to the same tag bus line by the cable 22, the adapter unit 14 must first select the drive unit 10 that sends a command. To select the drive unit 10, the adapter unit 14 puts the drive machine number to be selected on the bus between the adapter and the drive and issues a selection command to the tag.
Each drive unit 10 has a different machine number, and when it receives a selection command, it compares the machine number of the bus with its own machine number in advance, and if they are the same, the instruction from the adapter section 14 according to the following tag bus. To execute. Conventionally, the setting of the machine number of each drive unit 10 is done by the drive unit 10
It is set by switching the address setting switch such as the DIP switch provided on the printed board. But,
When setting the drive machine number by switching the switch,
A setting error is likely to occur, and if a setting error occurs, there will be multiple drive units 10 with the same drive model number. In this state, if a selection command is erroneously issued from the adapter unit 14 to the drive unit 10 for which the machine number has been set, a plurality of drive units 10 return responses at the same time, causing a bus fight. When such a double selection state occurs, the content of the interface signal is not guaranteed and normal control cannot be performed. Therefore, a drive machine number setting circuit shown in FIG. 5 has been considered. In the drive machine number setting circuit shown in FIG. 5, a printed board called a mother board 12 is used in order to simplify the cable connection of the interface circuit between the adapter section 14 and the drive section 10. That is, the tag / bus signal from the adapter unit 14 is transferred to the motherboard 12 via the cable 22.
Connected to. Motherboard 12 has multiple drive units
Ten printed boards are connected by a drive connector 16. In this example, the drive unit 10 is of eight types # 0 to # 7. An interface signal from the adapter unit 14 is connected in a pattern on the motherboard 12 to the drive connector 16 that connects the drive units 10 of # 0 to # 7 to the motherboard 12. Here, as shown in FIG. 6, the drive connector 16
Bits b0, b1 and b2 of the machine number setting signal are allocated to the three empty pins of the signal pins of. FIG. 6 exemplifies a 20-pin drive connector 16 in which bits b0 to b2 of the machine number setting signal are detected by the pins indicated by ●. The adapter connector 16 is 20
I made a pin, but this can be any number of pins. The pin marked with a circle is an interface signal pin or an empty pin. ● Bits b0 to b2 by pins marked with are 1, 2, 4 in decimal
As shown in the table of FIG. 7, pins ~ of the drive connector 16 are connected to GND on the motherboard 12 according to the machine numbers of # 0 to # 7.
Set to 0) and released from GND to H level (=
It is set to 1). The machine number of each drive unit 10 can be set by detecting the bits b0 to b2 determined by the logic level state of this pin to each drive unit 10. Therefore, the drive unit number can be automatically set only by connecting the drive unit 10 to the mother board 12 by a connector, and a setting error can be reliably prevented.

[Problems to be Solved by the Invention]

However, in the conventional drive machine number setting circuit using the motherboard 12 of FIG. 5, since the eight drive units 10 are connected to one motherboard 12, the printed board of the motherboard 12 becomes large. There is. Therefore, as shown in Fig. 8, connect the motherboard with 12A and 1A.
There are 2 different types of 2B. In other words, motherboard 12A is for drives # 0 to # 3, motherboard 12B is #
It is for 4th to # 7 drives. As shown in FIGS. 6 and 7, the drive collector 16 that connects each of the motherboards 12A and 12B to the drive unit 10 has a pin (-) as a bit b0 of the machine number setting signal of each drive unit 10. It is set on motherboards 12A and 12B as shown in ~ b2. However, in the conventional example of FIG. 8, it is possible to divide the mother board into two and make each printed board small, but since the machine numbers of the mother boards 12A and 12B are different,
It is necessary to prepare different types of motherboards, which causes an increase in the number of parts and an increase in cost. The present invention has been made in view of the above conventional problems, and a magnetic disk device capable of automatically setting a machine number for a drive unit by connecting a drive machine number connector to a common motherboard divided into a plurality of sheets. It is an object of the present invention to provide a drive device number setting circuit in the interface circuit of.

[Means for Solving the Problems]

FIG. 1 is an explanatory view of the principle of the present invention. First, according to the present invention, a plurality of drive units 10 to which different machine numbers are set, at least two motherboards 12 for collector-connecting a predetermined number of printed boards of the drive units 10 and a specific drive unit 10 are provided. A drive device number setting circuit used for an interface circuit of an apparatus provided with an adapter section 14 for transmitting / receiving a signal via a cable 22 of a tag bus line under the control of a host apparatus. According to the present invention as such a drive device number setting circuit, a plurality of drive connectors 16 for connecting the drive unit 10 to the motherboard 12, an adapter connector 18 for connecting the adapter unit 14, and the following Motherboard
A connector 20 for a mother board for connecting 12 is provided, and a predetermined number of connector pins of a plurality of connector 16 for a drive is connected to a binary logic level 0 or 1 (L or H) to set different machine number lower bits. After setting, and connecting specific pins of the connector pins of the plurality of drive connectors 16 and the adapter connector 18 in common, external connection to the adapter connector 20 brings the binary logic level to 0 or 1 (L or H). Set different machine number upper bits for each motherboard 12 and set a plurality of drive units 10 on each of at least two motherboards 12 connected in series to the adapter unit 14.
It is characterized in that different machine numbers are automatically set in the drive unit 10 by connecting to the connector. As a specific example, for example, two motherboards 12 provided with four drive connectors 16 are connected in series to an adapter section 14, and drive connectors provided on each motherboard 12 are connected.
Two of the 16 connector pins are sequentially set to binary logic level 0
Connected to 0,01,10,11 (LL, LH, HL, HH) and machine number lower bit b
0, b1 are set, and specific pins of the adapter connector 18 and the drive connector 16 of the mother board 12 located at the preceding stage are connected to the binary logic level 1 (H) to set the machine number upper bit b2. , Motherboard 12 located at the rear stage
The specific pins of the adapter connector 18 and the drive connector 16 are connected to the binary logic level 0 (L) to set the machine number upper bit b2 having a different value. Furthermore, the setting of the machine number upper bit that connects the specific pin of the adapter connector 18 and the drive connector 16 of the motherboard 12 located at the rear stage to 0 of the binary logic level is performed by setting the termination resistor to the adapter connector 18 in the empty state. 24 is set by connecting the connector from the outside.

[Action]

According to the drive machine number setting circuit of the present invention having such a configuration, different machine number upper bits are set for each motherboard by an external connector connection, and the machine number lower bits are commonly set for each motherboard. For this reason, even if the motherboard is divided into two, the drive number can be set automatically by connecting multiple adapters using a common motherboard, and the motherboard can be divided into multiple printed boards. Only one type is required, the manufacturing control of parts can be simplified, and the cost can be reduced. Also, the termination resistance that determines the machine number upper bits b2 = 0 of the final-stage motherboard can easily be used by using the connector with a built-in termination resistor used to terminate the interface signal. Can be set to a logic level of 0.

【Example】

FIG. 2 is a block diagram of an embodiment showing an embodiment of the present invention. In FIG. 2, reference numeral 14 denotes an adapter unit of the magnetic disk device, which performs section and control for the drive unit 10 side based on a command from the host device. In this embodiment, two motherboards 12, 12 are connected to the adapter section 14 in series by a cable 22 which constitutes a tag bus line. Here, the motherboard of the previous stage located on the adapter section 14 side
12 is # 0, and the motherboard 12 located at the latter stage (final stage) is # 1. The two motherboards 12 indicated by # 0 and # 1 are composed of printed boards having the same pattern. Each of the # 0 and # 1 motherboards 12 is provided with four drive connectors 16 for connecting the drive unit 10, and a motherboard for connecting between the adapter connector 18 for connecting the adapter unit 14 and the motherboard 12. Connector 20
Is provided. It should be noted that the number of motherboard connectors 20 is one in this embodiment because two motherboards are used, but if three or more are used, two motherboard connectors 20 are provided. # For the motherboard 12 located in front of 0,
Four drive units 10 to 0 to # 3 are connected to the drive connector 16 by connector connection of the printed circuit board. Also, the # 1 motherboard 12 located at the rear stage
, The printed circuit boards of the drive units 10 of # 4 to # 7 are connected to the drive connector 16 by connector connection. The cable 22 from the adapter section 14 is connected to the adapter connector 18 of the mother board 12 of # 0 in the preceding stage, and the cable 22 is connected between the mother board connector 20 of the mother boards 12 of # 0 and # 1. Connected. Further, a termination unit 26 having a built-in termination resistor for terminating an interface signal by a cable 22 as a tag bus line is connector-connected to the adapter connector 18 of the # 12 mother board 12 in the subsequent stage. FIG. 3 shows a drive connector 16 and an adapter connector 18 provided on the mother board 12 of # 0 and # 1 of FIG.
FIG. 3 is an explanatory diagram showing a connection state of a mother board connector 20. In FIG. 3, the drive connector 16, the adapter connector 18 and the motherboard connector 20 provided on each of the mother boards 12 are those having 20 pins shown in FIG. 6, for example. First of all, the connectors 16 and 1 of the motherboard 12 of # 0 and # 1
The interface signals between the adapter section 8 and 20 are commonly connected to the cable 22 as a tag bus line by a predetermined number of pins, but in this embodiment, the tag bus line is connected to simplify the description. It is shown by one signal line, and a plurality of pins are represented by one pin as a representative. On the other hand, with respect to the drive connector 16, among the 20 pins, three empty pins indicated by are used for setting the drive machine number. Further, for the adapter connector 18, an empty pin at the same position as the pin in the drive connector 16 is assigned for setting the drive machine number. Bits b0, b1, and b2 of the machine number setting signal are assigned to the pins of the drive connector 16 and are weighted in decimal.
1, 2, 4 are attached. Each of the four drive connector 16 pins is a # 0 and # 1 motherboard 12
Both of them are connected to the mother board 12 so that the L level is indicated by a white circle and the H level is indicated by a black circle. That is, for the L level indicated by the white circle,
It is realized by connecting to GND on the motherboard 12, while the H level indicated by the black circle is GN on the motherboard 12.
It is realized by releasing from D and pulling up to the power supply voltage. Therefore, in each of the # 0 and # 1 motherboards 12, the pins of the drive connector 16 are LL, LH, HL, HH as the lower two bits b1 and b0 of the drive machine number setting signal.
That is, 00, 01, 10, 11 are set. The pins for setting the machine number upper bit b2 of the drive connector 16 provided on each of the # 0 and # 1 motherboards 12 are connected in common by the signal line 28 and then connected to the pins of the adapter connector 18. Since the terminating resistor 24, which will be described later, is not connected to the pin of the adapter connector 18 on the # 0 motherboard 12 located in the previous stage, the pin is in the H level state and the signal line The pins of the drive connector 16 commonly connected by 28 are also set to the H level. On the other hand, in the # 1 motherboard 12 located in the subsequent stage, the termination unit 26 shown in FIG. 2 is connected to the pin of the adapter connector 18 commonly connected to the pin of the drive connector 16 by the signal line 28. Accordingly, the terminating resistor 24 is connected, so that the pins of the adapter connector 18 and the drive connector 16 on the # 1 motherboard 12 are all set to the L level. Therefore, the most significant bit b2 of the machine number setting signal set by the pin in the drive connector 16 of the motherboard 12 located at the preceding stage is b2 = H level, while the most significant bit b2 for the drive of the motherboard 12 at # 1 located at the subsequent stage. The most significant bit b2 of the machine number setting signal set in the pin of the connector 16 becomes b2 = L level. Here, eight drive units 10 # 0 to # 7 shown in FIG.
Assuming that the machine number setting signal of is set as shown in the table of FIG. 7, each mother board 12 of # 0 and # 1 shown in FIG.
By setting H or L of the machine number setting signal bits b2, b1, b0 determined by the pins of the drive connector 16 provided in
When the drive unit 10 is connected to the connector as shown in the figure, #
Drive machine number # 0 in order from the top of the motherboard 12 of No. 1
.About. # 3 are set, and for the mother board 12 located at the rear stage, # 4 to # 7 are automatically set from the upper side. In the above embodiment, the motherboard 12 is divided into two, # 0 and # 1.
Although the case where the sheet is divided is described as an example, the sheet may be divided into three or more sheets. When the number of the mother boards 12 is three or more, two mother board connectors 20 of each mother board shown in FIG. 2 are provided so that they can be connected in series one after another, and for identifying the mother board shown in FIG. In addition to the pins, increase the number of free pins by adding one more empty pin and connect them to the corresponding pins of the adapter connector 18 in common with the signal line. Just go. The embodiment shown in FIG. 2 is an example in which four drive units 10 are connected to one motherboard 12, but when the number of drive units 10 is increased, the number of drive units may be increased. The number of pins used for setting the machine number of the drive connector 16 may be increased corresponding to the number of bits used for the machine number setting signal.

【The invention's effect】

As described above, according to the present invention, the drive device number can be automatically set only by connecting the printed circuit board of the drive unit to the motherboard, and setting mistakes can be prevented. By dividing it into pieces, the printed board of the motherboard can be made smaller,
Furthermore, even if a plurality of motherboards are used, the same kind of motherboard is sufficient, so that manufacturing and management can be facilitated and cost can be reduced. For setting the above bits of the machine number setting signal used to identify the motherboard, use the terminating resistor connection unit on the terminating side for the interface signal to enable easy identification of the motherboard. You can decide.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the principle of the present invention; FIG. 2 is a configuration diagram for an embodiment of the present invention; FIG. 3 is a diagram for explaining a mother board connection of the present invention; FIG. 4 is a diagram for explaining an interface circuit of a conventional disk device; FIG. 5 is an explanatory view of a conventional circuit using a mother board; FIG. 6 is an explanatory view of a drive connector of FIG. 5; FIG. 7 is an explanatory view of machine number setting by the drive connector of FIG. 5; It is explanatory drawing of the conventional circuit which divided the motherboard into two. In the figure, 10: Drive part 12: Motherboard 14: Adapter part 16: Drive connector 18: Adapter connector 20: Motherboard connector 22: Cable (for tag bus line) 24: Termination resistor 26: Termination unit 28: Signal line

Claims (3)

(57) [Claims] 1. A plurality of drive units (10) to which different machine numbers are set, at least two motherboards (12) for connecting a predetermined number of printed boards of the drive units (10) by connectors, and the identification. In the interface circuit of the device, which is provided with an adapter unit (14) for transmitting and receiving a signal to and from the drive unit (10) of the host device through the cable (22) of the tag bus line under the control of the host device, A plurality of drive connectors (16) for connecting the drive section (10) to each of the motherboards (12);
An adapter connector (18) for connecting the adapter section (14) and a motherboard connector (20) for connecting another subsequent motherboard (12) are provided, and connectors for the plurality of drive connectors (16) are provided. Among the connector pins of the plurality of drive connectors (16) and adapter connector (18), a predetermined number of pins is connected to binary logic level 0 or 1 to set different machine number lower bits. After the common connection of the specific pins of the adapter connector (20), it is connected to the binary logic level 0 or 1 by external connector connection to set a different machine number upper bit for each motherboard. ) Is connected to each of the at least two motherboards (12) connected in series by a plurality of drive units (10), the drive units (10) are automatically connected. Drive machine number setting circuit and sets a different machine number. 2. The drive machine number setting circuit according to claim 1, wherein two motherboards (12) having four drive connectors (16) are connected in series to an adapter section (14),
The drive connector (1
Two of the 6) connector pins are set to binary logic level 00,0
Connect to 1,10,11 and set the machine number lower bits (b0, b1),
Also, by connecting the specific pin of the adapter connector (18) and the drive connector (16) of the motherboard (12) located in the previous stage to the binary logic level 1, the machine number upper bit (b2)
Motherboard to be set and located at the rear stage (12)
A drive device number setting circuit, characterized in that specific pins of the adapter connector (18) and the drive connector (16) are connected to binary logic level 0 to set the device number upper bit (B2). 3. The drive machine number setting circuit according to claim 2, wherein the specific pins of the adapter connector (18) and the drive connector (16) of the motherboard (12) located at the subsequent stage are set at a binary logic level. Setting of the machine number upper bit (b2) by connecting to 0 of the drive machine is characterized by externally connecting the terminating resistor (24) to the adapter connector (18) in the empty state. Number setting circuit.