Step Technica MKY02 User manual

HUB-IC MKY02
User’s Manual
(for CUnet)
STD_CUH02_V1.6E

Note
1. The information in this document is subject to change without prior notice. Before using this
product, please confirm that this is the latest version of this document.
2. Technical information in this document, such as explanations and circuit examples, are refer-
ences for this product. When actually using this product, always fully evaluate the entire sys-
tem according to the design purpose based on considerations of peripheral circuits and the
PC board environment. We assume no responsibility for any incompatibility between this
product and your system.
3. We assume no responsibility whatsoever for any losses or damages arising from the use of
the information, products, and circuits in this document, or for infringement of patents and any
other rights of a third party.
4. When using this product and the information and circuits in this document, we do not guaran-
tee the right to use any property rights, intellectual property rights, and any other rights of a
third party.
5. This product is not designed for use in critical applications, such as life support systems. Con-
tact us when considering such applications.
6. No part of this document may be copied or reproduced in any form or by any means without
prior written permission from StepTechnica Co., Ltd..
Trademark "HLS" is licensed by Murata Manufacturing Co., Ltd.

MKY02 User’s Manual
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Preface
This manual describes the MKY02, or a kind of HUB-IC in the CUnet.
Be sure to read “CUnet Introduction Guide” before understanding this manual and the MKY02.
zTarget Readers
This manual is for:
yThose who first build a CUnet
yThose who first use StepTechnica's various ICs to build a CUnet
zPrerequisites
This manual assumes that you are familiar with:
yNetwork technology
ySemiconductor products (especially microcontrollers and memory)
zRelated Manuals
yCUnet Introduction Guide
yCUnet Technical Guide
yCUnet IC Manuals
[Caution]
ySome terms in this manual are different from those used on our website and in our product bro-
chures. The brochure uses ordinary terms to help many people in various industries understand
our products.
Please understand technical information on HLS Family and CUnet Family based on technical
documents (manuals).

MKY02 User’s Manual (for CUnet)
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CONTENTS
Chapter 1 Concepts for Using MKY02 (HUB)
1.1 Role of MKY02 ....................................................................................................... 1-3
1.2 Basic CUnet Configuration................................................................................... 1-3
1.3 CUnet Configuration using HUBs........................................................................ 1-4
1.3.1 Extending Total Length of Network Cable ................................................................ 1-4
1.3.2 Branching Multi-dropped Network Cables................................................................ 1-6
1.3.3 Eliminating Connection or Disconnection of
Termination Resistor to or from Each Device .......................................................... 1-7
1.3.4 Star Topology ..............................................................................................................1-8
1.4 Basic HUB Connection ......................................................................................... 1-9
1.5 Multi-drop Network of HUBs .............................................................................. 1-10
1.6 Port Addition to HUB .......................................................................................... 1-11
1.7 MKY02 Operation ................................................................................................ 1-12
1.7.1 Receiving and Sending Packets .............................................................................. 1-12
1.7.2 Signal Correction....................................................................................................... 1-13
1.7.3 Detection of Error Packet ......................................................................................... 1-13
1.8 Features of MKY02 .............................................................................................. 1-14
Chapter 2 MKY02 Hardware ................................................................................2-3
Chapter 3 Single Connection of MKY02
3.1 Voltage Levels of Pins Connecting to Signal Pins............................................. 3-4
3.2 Supplying Driving Clock and Hardware Reset Signal ....................................... 3-5
3.2.1 Supplying Driving Clock ............................................................................................. 3-5
3.2.2 Setting Cascade Clock and Baud Rate...................................................................... 3-6
3.2.3 Hardware Reset ........................................................................................................... 3-7
3.3 Connecting Network Interface ............................................................................. 3-8
3.3.1 Handling of FH Pin ...................................................................................................... 3-8
3.3.2 Connection of Port 0 ................................................................................................... 3-8
3.3.3 Connection of Ports 1 to 7......................................................................................... 3-9
3.3.4 Recommended Network Connection....................................................................... 3-10
3.4 Connecting Monitor LEDs .................................................................................. 3-11
3.4.1 Packet Receive Monitor ............................................................................................ 3-11
3.4.2 Packet Error Monitor ................................................................................................. 3-12
3.4.3 Port Receive Monitor................................................................................................. 3-13
3.5 Handling Cascade Connection Pins.................................................................. 3-15
3.6 Cautions for Designing HUB .............................................................................. 3-15
3.7 Example Circuit for Single Connection of MKY02 ........................................... 3-16

MKY02 User’s Manual
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Chapter 4 Cascade Connection of MKY02
4.1 Concepts of Port Addition.................................................................................... 4-3
4.1.1 Port Addition by Stacking Method............................................................................. 4-3
4.1.2 Port Addition by Cascade Connection ...................................................................... 4-4
4.1.3 Maximum Available Cascade Connections............................................................... 4-4
4.2 Practical Side of Cascade Connection................................................................ 4-5
4.2.1 Cascade Pins ...............................................................................................................4-5
4.2.2 Operation of Cascade Connection Pins .................................................................... 4-6
4.2.3 Connection of Cascade Clocks and Determination of Baud Rate .......................... 4-7
4.2.4 Connection of Hardware Reset Signal ...................................................................... 4-8
4.2.5 Handling of Each FH Pin............................................................................................. 4-8
4.2.6 Connection of Each Port............................................................................................. 4-8
4.2.7 Placement of Monitor LEDs........................................................................................ 4-9
4.3 Example Circuit for Port-added HUB by Cascade Connection....................... 4-10
Chapter 5 Ratings
5.1 Electrical Ratings .................................................................................................. 5-3
5.2 AC Characteristics ................................................................................................ 5-3
5.2.1 Clock and Reset Timing.............................................................................................. 5-4
5.2.2 Port Pin Timing (TXE0 to 7, TXD0, TXD17, RXD0 to 7)............................................. 5-5
5.2.3 Cascade Connection Pin Timing................................................................................ 5-6
5.2.4 Output Timing of #LEDRCV and #LEDRZE Pins ...................................................... 5-6
5.2.5 Timing of Receive Monitor Pin of Individual Port (RLLD, RLDT, RLCK) ................ 5-7
5.3 Package Dimensions ............................................................................................ 5-8
5.4 Recommended Soldering Conditions ................................................................. 5-9
5.5 Recommended Reflow Conditions ...................................................................... 5-9

MKY02 User’s Manual (for CUnet)
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Figures
Fig. 1.1 Basic CUnet Configuration .......................................................................... 1-3
Fig. 1.2 Extension of Network Cable Length ........................................................... 1-4
Fig. 1.3 Multipoint Connection of Network Cables.................................................. 1-6
Fig. 1.4 Eliminating Problems with Termination Resistors .................................... 1-7
Fig. 1.5 Star Topology................................................................................................ 1-8
Fig. 1.6 Basic Connection and Number of Inserted HUBs ..................................... 1-9
Fig. 1.7 HUB in Intermediate Position of Multi-drop Network .............................. 1-10
Fig. 1.8 Adding Ports by Cascading MKY02s ........................................................ 1-11
Fig. 1.9 Number of Inserted HUBs with Added Ports............................................ 1-11
Fig. 1.10 MKY02 Operating Principles...................................................................... 1-12
Fig. 1.11 Example of Signal Transformation and Correction ................................. 1-13
Fig. 2.1 MKY02 Pin Assignment................................................................................ 2-3
Fig. 2.2 Pin Electrical Characteristics in I/O Circuit Types of MKY02 ................... 2-6
Fig. 3.1 Connection Causing Leakage Current........................................................ 3-4
Fig. 3.2 Cascade Clock Generation .......................................................................... 3-6
Fig. 3.3 Clock Connection ......................................................................................... 3-6
Fig. 3.4 Hardware Reset............................................................................................. 3-7
Fig. 3.5 Handling of FH Pin........................................................................................ 3-8
Fig. 3.6 TRX Connection of Port 0 ............................................................................ 3-8
Fig. 3.7 TRX Connection of Ports 1 to 7 ................................................................... 3-9
Fig. 3.8 TRX Connection of HUB with 4 Ports ......................................................... 3-9
Fig. 3.9 Recommended Network Connection ........................................................ 3-10
Fig. 3.10 Connection of Receive Monitor LED......................................................... 3-11
Fig. 3.11 Connection of Packet Error Monitor LED ................................................. 3-12
Fig. 3.12 RLLD, RLDT, and RLCK Outputs............................................................... 3-13
Fig. 3.13 8-port Receive Monitor ............................................................................... 3-14
Fig. 3.14 4-port Receive Monitor ............................................................................... 3-14
Fig. 3.15 Handling of Cascade Connection Pins ..................................................... 3-15
Fig. 3.16 Example of Single Connection Circuit...................................................... 3-16

MKY02 User’s Manual
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Fig. 4.1 Addition of Three-stacked Ports ................................................................. 4-3
Fig. 4.2 Port Addition by Three Cascade Connections........................................... 4-4
Fig. 4.3 Cascade Pin Connection for Three MKY02s .............................................. 4-5
Fig. 4.4 Cascade Pin Connection for Two MKY02s................................................. 4-5
Fig. 4.5 Operation when Port 11 Receives a Packet ............................................... 4-6
Fig. 4.6 Operation when Port 23 Receives a Packet ............................................... 4-6
Fig. 4.7 Operation when Port 0 Receives a Packet ................................................. 4-6
Fig. 4.8 Connection of Cascade Clocks ................................................................... 4-7
Fig. 4.9 Monitor Placement Example for Port-added HUB ..................................... 4-9
Fig. 4.10 Example Circuit for HUB with 24 Ports..................................................... 4-10
Tables
Table 1-1 Baud Rates and Recommended Total Extension Number
of Inserted HUBs.......................................................................................... 1-4
Table 2-1 Pin Functions of MKY02.............................................................................. 2-4
Table 2-2 Electrical Ratings of MKY02........................................................................ 2-6
Table 3-1 Output Frequencies of Cascade Clocks .................................................... 3-6
Table 5-1 Absolute Maximum Ratings ........................................................................ 5-3
Table 5-2 Electrical Ratings......................................................................................... 5-3
Table 5-3 AC Characteristics Measurement Conditions ........................................... 5-3

MKY02 User’s Manual (for CUnet)
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Chapter 1 Concepts for Using MKY02 (HUB)
This chapter describes the concepts for using the MKY02 (HUB) in the CUnet.
1.1 Role of MKY02................................................................................1-3
1.2 Basic CUnet Configuration ...........................................................1-3
1.3 CUnet Configuration using HUBs ................................................1-4
1.4 Basic HUB Connection..................................................................1-9
1.5 Multi-drop Network of HUBs.......................................................1-10
1.6 Port Addition to HUB...................................................................1-11
1.7 MKY02 Operation.........................................................................1-12
1.8 Features of MKY02 ......................................................................1-14

Chapter 1 Concepts for Using MKY02 (HUB)
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Chapter 1 Concepts for Using MKY02 (HUB)
This chapter describes the concepts for use of the MKY02 (HUB) in the CUnet.
1.1 Role of MKY02
MKY02 is a kind of HUB-IC that constitutes a HUB to be used in the CUnet network.
Be sure to read the “CUnet Introduction Guide” and the “User’s Manuals” for the various CUnet ICs
before using the MKY02 and understanding this manual.
1.2 Basic CUnet Configuration
Figure 1.1 shows the basic CUnet configuration with CUnet ICs connected on a multi-drop network.
Rt in the figure indicates a termination resistor.
Some user systems may need the following for the basic CUnet configuration:
(1) To extend the total length of a network cable.
(2) To branch pieces of multi-dropped network.
(3) To eliminate connection or disconnection of termination resistor to or from each device.
There will be difficulty solving these needs using such basic CUnet configuration shown in Figure 1.1.

MKY02 User’s Manual (for CUnet)
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1.3 CUnet Configuration using HUBs
Adding HUBs to the CUnet network, the user system can satisfy it’s own needs (1) to (3) described above.
1.3.1 Extending Total Length of Network Cable
Adding HUB(s) to the CUnet network, the user can extend the total length of the network cable. Figure 1.2
shows an example of extending the total length of the network cable. Rt in the figure indicates a termination
resistor.
The user system can extend the recommended network cable length by adding the inserted count of HUBs
+1 to the basic CUnet configuration. For example, adding a single HUB doubles cable length, adding two
HUBs triples cable length. Table 1-1 shows the baud rates and the recommended total extension based on
the number of the inserted HUBs when using the recommended network connection.
Table 1-1 Baud Rates and Recommended Total Extension Number of Inserted HUBs
Number of inserted HUBs
Baud rate 0 (Basic configuration) 1 2
12 Mbps 100 m 200 m 300 m
6 Mbps 200 m 400 m 600 m
3 Mbps 300 m 600 m 900 m

Chapter 1 Concepts for Using MKY02 (HUB)
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The practical limit of network cable length varies with the performance of drivers/receiv-
ers, cable types, cabling environments, and how many cables are multi-drop connected.
StepTechnica's recommended network cable length is about 1/2 of the cable length limit
obtained from our practical experiments. These values are provided as a guide for stable
CUnet operation in various user systems (,but performance is not guaranteed).
Therefore, in many user systems, the user can use the network cable longer than the total
length shown in Table 1-1.
The maximum number of HUBs that can be added is up to two HUBs.

MKY02 User’s Manual (for CUnet)
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1.3.2 Branching Multi-dropped Network Cables
The network cables can be branched by adding HUBs to the CUnet network. Figure 1.3 shows an example
of an CUnet configuration in which network cables are branched.
Figure 1.3 shows the network cables that are branched in T shape. Adding a HUB using the MKY02 also
enables multiple branchings with many ports.

Chapter 1 Concepts for Using MKY02 (HUB)
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1.3.3 Eliminating Connection or Disconnection of Termination Resistor to or
from Each Device
In a network using the CUnet, termination resistors (Rt) cannot be connected to the terminal connected in the
intermediate position (the halfway position in the network cable) of the multi-drop network. However, a “one-
to-one” connection between all terminals can eliminate connection or disconnection of termination resistor to
or from each device and simplifies the complexity of system installation as shown in Figure 1.4.

MKY02 User’s Manual (for CUnet)
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1.3.4 Star Topology
Mounting a HUB-IC to the terminal containing the CUnet IC can offer a star topology (Fig. 1.5). Further-
more, network cables in a star topology can also be multi-drop-connected.

Chapter 1 Concepts for Using MKY02 (HUB)
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1.4 Basic HUB Connection
Figure 1.6 shows the basic connection of HUBs added to a CUnet network. The user must know the number
of HUBs to be added in the route of all routes that pass most frequently through the HUB. The number of
added HUBs is called the “number of inserted (HUBs)”. The “number of inserted” HUBs is determined by
the type of the CUnet IC and settings made to CUnet ICs by the user system. There are no restrictions on
which device must be connected to which port, etc., at HUB connection.
The user can add up to two HUBs in a CUnet system.
The figure “When three HUBs are inserted” is not compliant with a system.

MKY02 User’s Manual (for CUnet)
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1.5 Multi-drop Network of HUBs
When adding HUBs to the CUnet, the user can connect HUBs as multi-drop (Fig. 1.7).
The multi-drop network of HUBs is suitable for a user system in which the network cables should be
divided.
The number of inserted HUBs shown in Figure 1.7 is “2”.
As shown in Figure 1.7, in cases where port 0 of the HUB is placed in the intermediate position (the halfway
position in the network cable) of a multi-drop network, do not connect a termination resistor to the port 0.
For details of the connection of a termination resistor, refer to “CUnet Technical Guide”.

Chapter 1 Concepts for Using MKY02 (HUB)
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1.6 Port Addition to HUB
By cascading MKY02s, the user can add more ports to a HUB composed of the MKY02.
For example, a cascade connection of three MKY02s enables the HUB to have 24 ports (8 ports ×3)
(Fig. 1.8).
If a HUB with ports added by cascading MKY02s is added to a network, the number of inserted HUBs
between user equipments connected to each port of the HUB is “1” (Fig. 1.9).
Adding ports by cascading MKY02s is helpful to setup cables on multi-drop network or star topology. For
details of cascading MKY02s, refer to “Chapter 4 Cascade Connection of MKY02”.

MKY02 User’s Manual (for CUnet)
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1.7 MKY02 Operation
This section describes the operation of the MKY02. Be sure to read this section before adding HUBs to the
CUnet.
1.7.1 Receiving and Sending Packets
When the MKY02 receives a packet from any port, it corrects the signal constituting the received packet into
a complete format and sends it to all other ports, resulting in a maximum time lag of “46 × T
BPS ” from
receiving to sending packet to correct the received packet into a complete format (Fig. 1.10).
Each port of the MKY02 has priorities based on the port number. When multiple ports receive packets
simultaneously, the MKY02 starts operation in ascending order of the port numbers (Fig. 1.10).
Most of communication HUBs other than StepTechnica's are designed to start sending after
receiving the full packet length. This mechanism decreases the signal response speed of
the entire system significantly, in particular in a system with inserted a lot of HUBs. As
shown in Figure 1.10, the MKY02 sends the corrected packet while receiving the packet,
which causes only a slight decrease in the signal response speed of the entire system.
In a CUnet that operates correctly, multiple CUnet ICs never send packets simultaneously.
Therefore, a packet collision like that shown in Figure 1.10 never occur in a CUnet that
operates correctly.