Micrel Serial Programmer
(MICUSB)
User G uide
The Micrel Serial Programmer (MICUSB) is a hardware and software solution supporting Micrel’s I2C, SWI, and
other serial bus based products. MICUSB operates as a bus master to communicate with slave devices using a
USB-to-serial conv erter, supporting b oth generic bus interface mode and hardware-specific profiles for c omm and
and control of Micrel semiconductor products.
Note that MICUSB − and supported Micrel ICs − require the use of a USB-to-serial programmer for proper
operation. The dongle is NOT provided with the Micrel IC evaluation boards and must be purchased separately.
Introduction
Micrel’s MI CUSB solut ion allows a ny PC with th e hardware don gle and s oftware ins talled to act as a mas ter for a
large num ber of c ommunic ation interf aces. T his contr ol is used to direct ly comm unicate with and c ontrol Mi crel’s
communication-enabled power management ICs.
Features
Key features of the MICUSB include:
• Serial communication with a large number of power-management products
• Byte wise serial access to device registers
• Compatible with any USB port
• Graphical user interface (GUI) support allows graphical editing of programmable settings.
• Off-line programming allows you to configure and save register settings for later use
• On-line programming allows you to directly modify attached device registers in real time
• 3.3V or 5V optional on-board pull-ups with 5V-tolerant IO for I2C bus products
• Additional logic level translator modules for different IO voltage requirements
• Protocol support:
− I2C in standard mode (100kbps), fast mode (400kbps), fast mode+ (1Mbps), and high-speed mode
(3.4Mbps)
− Micrel’s pr oprietar y single-wire interfac e (SW I) for com munication us ing a s ingle c onductor an d operat ing
up to 6Mbps
− MIPI RFFE interface at up to 30Mbps
− 4-channel PWM output interface
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • US A • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
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Micrel Serial Programmer (MICUSB) − User Guide
Hardware
Communication
The I2C interface is implemented using the standard I2C communications protocol at standard, fast, fast mode
plus, and high speed modes, operating exclusively as bus master. Support is provided for the FT232H-based
USB to serial interface con verters. The IC operates using FTDI MPSSE m ode, which allows the I2C interf ace to
be operated at full native speed while minimizing the number of USB communications. Bit-based mode is also
supported for some protocols.
MICUSB I2C Dongle
The FT232H-based MICUSB dongle is a 480Mbps USB 2.0 high-speed mode device offering improved
communication speed and capability for advanced interface products. V2 supports fast and nonstandard buses,
such as SWI and system power-management interface (SPMI) with serial data rates up to 30Mbps. The dongle
can also be used in high-speed I2C up to 3.4Mbps while maintaining backward compatibility with the V1 dongle.
The dongle provides additional GPIO output for up to 8 bits of data arranged as 2 × 4 bit parallel bus with two
serial interfaces or as an 8 independent bit bashed IO. Both 5V (USB bus), and 3.3V (FTDI) internal regulator
power rails are made available (via Pin 5, 0.1” JP1 header).
Figure 1. MICUSB I2C Dongle and Features
I2C Configuration
For I2C systems, it is necessary to configure the FT232H for bidirectional data bus by connecting the data-out to
the data-in pin. This is accomplished by setting the slide switch SW1 to the I2C posit io n.
Adding I2C Bus Pull-Ups
For I2C systems , additional pull-ups can be enabled fo r SDA via R11 and SCL via R12 to either the 5V U SB bus
input or th e 3.3V bus input. To do this, a sh ort should be p laced on Pin 2 a nd Pin 3 on JP1 for 5.0V or bet ween
Pin 3 and Pin 4 on JP1 for 3.3V pull-up. By default JP1, R11, and R12 are not populated and no bus pull-up is
present.
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Micrel Serial Programmer (MICUSB) − User Guide
Figure 2. Top and Bottom Views of the MICUSB Dongle
Starting the GUI and Connecting to an Interface
Start b y plugging i n the U S B-to-s er ial c onv erter bef or e s tarting the G UI. When running the G UI f or the f irs t time, it
will automatically attempt to find and install the driver for the FTDI dongle. After the installation is complete, the
GUI can be started.
The GUI can be started either by launching the program file via the desktop icon or the start menu item, or by
double clicking on any “.mrg” file. The latter will automatically start up the GUI and load the register description
file, allowing programming to commence as soon as the GUI starts.
At startu p th e G UI wi ll f irs t c heck for the “ftd2xx.dll” file, and then attempt to communicate with the USB d ong l e. If
an error is detec te d, the G U I wil l infor m the user with a warni ng di al og i llus tr ated in Figure 3. In t he event th at this
box is display either at start up or when switching profiles, first check the dongle is connected. If the problem
persists then remove and replace the dongle to clear the error.
Figure 3. Dongle “Not Connected” Warning Message
It is possible to ignore the start-up issue to launch the program without a USB converter, but functionality will be
limited. Mul tip le GUI i ns tan c es us ing multiple dong les ar e s upporte d, but must be started one at a t ime for c orrec t
operation. At GUI start-up where multiple USB converters are present, the software will automatically and non-
deterministically select the first device it finds.
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Micrel Serial Programmer (MICUSB) − User Guide
Quick Start Guide
The Quick Start Guide demonstrates provides a full description of the GUI features and options while detailing
how to install the GUI, get it connected to the serial programming dongle, and configure the GUI to program an
external Micrel IC.
Setting Up
Obtaining and Installing the GUI
The GUI can be downloaded from Micrel’s web site at www.micrel.com or alternatively contact your local Micrel
distributor to obtain a cop y of the GUI and the ser ial progr amm er hardware. T he sof tware is spec if ic to the Micrel
product so please visit the product page of interest to get the required software.
Run the “setup.exe” file in the installation folder to start the installation wizard, and follow the on-screen
instructions to set up the GUI software.
Connecting
After instal lin g the G UI, the dong le must be plugge d int o an ava ilab le US B por t on the hos t machine. Af ter a shor t
wait, the dr ivers should be automatically installed. Ple ase note t hat this pr ocess coul d take s ome tim e and can be
different depending on your operating system.
Starting the GUI
The GUI can be started in one of t wo ways:
1. Launch the shortcut that appear s on the desktop or in the start menu
2. Double-click on an y registe r f ile (spec ificall y any file nam e with an “.mrg” extension). The options available in
the start menu are based on profiles that are currently installed on the user machine with “.mrg” files
containing either a full or partial copy of a complete register set-up and can be saved or loaded by the GUI
software. Starting the GUI via the “.mrg” register file will perform the following actions:
− Load the GUI
− Load the device profile indicated in the file
− Update any register settings with the values in the file
Figure 4. Starting the Programming GUI using the Start Menu (left) and using a Register Description File (right)
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Micrel Serial Programmer (MICUSB) − User Guide
Profiles
The GUI supports multiple slave device configurations and provides device specific macro communications
options f or directly drivi ng target IC’s. W hen select ing a prof ile, the “Comm unication Bus ”, “Destinatio n Address ”,
“Number of Registers”, “Register Address 0x00”, and the “Register Polling Address” fields are automatically
populated. The “Number of Registers” and “Register Address 0x00” fields are fixed and cannot be edited when
using a device profile.
When a profile is active, hovering the mouse over any of the “Register Address”, “Data”, or “Read Only”
edit/check boxes while in the “Registers” tab will display a dynamic tooltip. The tooltip shows a bit field view
containing register bit field locations and sizes, read/write access, current value in binary, value on power-on-
reset (POR) condition, and bit field name (refer to Figure 5). The Generic Operations and Generic Mode section
details a complete description of the supported profiles and how they are used.
Figure 5. Dynamic Register Description “Mouseover”
Test the Interface
Before the interface and target device can be read or written, the GUI enforces a mandatory test of the PC <->
USB Dongle <-> Target Hardware. To do this just press the “Test” button in the “Target Config.” tab. Upon
successful completion, the “Read” and “Write” buttons inside the “Registers” tab will be enabled (refer to Figure
6).
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Figure 6. Mandatory Interface Test Mode
Configure for Dynamic Register Configuration
The GU I supports two m odes of operation: O ffline and direc t edit. Offline mode acts as a simulation environment
where register updates are simulated by the GUI but no communication is performed. Direct edit mode acts as an
emulation m ode where th e PC will mas ter the bus and s end comm ands to the slave device(s). To allow d yn amic
“on-the-fly” updati ng of the IC r egisters, the offline mode m ust be chan ged to direc t edit mode. This c an be done
by either pressing the blue-highlighted offline mode menu button to toggle the mode, or by selecting Link > Link
Mode > Direct Editing Mode option from the main menu.
Figure 7. Selecting Offline Mode or Direct Editing Mode
After c ompleting d ynamic register co nfiguratio n, the dev ice is no w read y to be connect ed and co nfigure d to allo w
access to all regis ters setti ngs directl y either vi a changes to t he register map on the left pan e, or b y adjusting th e
device controls in the right pane.
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Micrel Serial Programmer (MICUSB) − User Guide
Software
Supported Operating Systems
The GU I applicatio n is based o n the .N ET framework, Version 3.5. T he app lication h as been tes ted on M icrosof t
Windows XP, Windows Vista, Windows 7 and Windows 8.
Installer
Run the “setup.exe” package in the installation folder. The installation wizard will appear and guide you through
the rest of the set-up proce ss . After com pletion, t he s oftware will instal l shor tcuts to the m ain appl ication profiles,
uninstall, and the user gu ide in the start menu. Additionall y, the installer will register the “.mrg” file extension so
that the application can automatically launch when running a file with an “.mrg” extension.
“ftd2xx.dll”
The hardw are i nter f ac e req uir es the “ftd2xx.dll” f ile to e ither b e inst al led o n the system or be available i n th e s ame
folder as the executable. While the package includes this “ftd2xx.dll” file, it can also be downloaded from the
FTDI website at: www.ftdichip.com.
GUI Menu Options
File Menu
Registe r Setting (Load/Save)
The current GUI configuration, including the I2C address, profile support and current register settings can be
saved an d rec al le d at any tim e via the F il e > Re gister Sett ings > Menu (see Figure 8) an d th e f ile is s aved with an
“.mrg” extension in a human readable form at. Figure 9 is an example of a small register description f ile. It is not
recom mended that the user edits the generated f ile as only limited err or checking is carried out b y the GUI when
reading the file.
Figure 8. Register Setting Load and Save
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Micrel Serial Programmer (MICUSB) − User Guide
Figure 9. Small Register Description File Example
Profiles
The F ile > Profiles menu conta ins a list of all curr entl y installed hard ware profiles . Selecting on e of these op tions
will cause the GUI to unload the current profile and switch to the new profile.
Register Defaults
The File > Register Defaults menu option provides a method of recovering the default register values for each
register disp layed by t he GUI without m anually re-entering e ach value and with out restartin g the GUI. If a profile
is active, the r egister d efault values will be tak en from the reg isters desc ription file for the IC , which represen t the
POR register values. If no pr of ile is ac ti ve then each o f the displayed register valu es will be cl e ar ed to zero. Note
that if direct edit mode is active, the register values will also be reprogrammed to the hardware.
Options
The File > Options menu option displays the settings window (refer to Figure 10). These non-volatile settings
configure various options of the system and reloaded at each start up.
Figure 10. Options Dialog
Drive I2C SDA/SCL Line
Enabling this option (checked) will make the I2C interface drive the SD A and SCL signa ls high inste ad of tri-stating
the out put driver for a h igh log ic level. In som e situati ons, it m ay be useful to n ot ha ve I2C bus pull ups on either
the target or the dongle. In this situation, the I2C interface can be configured to directly drive the SDA and SCL
lines in high mode, instead of relying on the external pull ups.
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Micrel Serial Programmer (MICUSB) − User Guide
Operating Modes
Link Mode
Two gener al oper ating m odes are s upported for acc essing t he regist ers. T hese can be selected w ithin the Link >
Link Mod e menu. T hes e op tions c o ntr ol ho w th e d ata enter e d int o the r eg ister s and GUI elements are sent t o an d
from the remote serial device; either d ynamically as they are modified, or manually by pressing the “Read/Write”
buttons. The current mode is also displayed in bold blue in the menu bar of the GUI, which can also be used to
toggle between t he t wo modes .
Figure 11. Link Mode Menu Option
Direct Editing Mode
In direct edit mode, an y rea d or write t o the re gister da ta fields will imm ediate ly iss ue a re ad or write o perat ion o n
the serial interface. Register read/write is initiated by manually editing the register data sections or when the
hardware specific profile controls accessing the register data are interacted with. Note that read-only flags are
active in dir ect edit m ode and override an y other read/wri te enable m echanism , so any attem pt to write to a read-
only byte will be ignored.
Offline Mode
In offline mode, r egister access via the user -profile contr ols will not direc tly be issued to har dware. Inste ad, data
edits will be stored locally and hardware-specific profile controls will act only on the local register copy (as
displayed in the GUI). To send the reg is ter co nt en ts t o a de vice v ia th e s eri al i nter face, the “Write” button m us t be
pressed. If no USB-to-serial dongl e is pr esent, then th e G UI can s til l be us ed to g ener at e s uit abl e reg is ter s ettin gs
and then save the register settings to file for later use. Note that offline mode can also be used with an external
I2C dongle. In this s c enario , the “Read” and “Write” buttons are pres ent a nd c an b e us ed to r ead a nd program t he
existing register settings on demand.
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Micrel Serial Programmer (MICUSB) − User Guide
Source
Generate
This m enu allows the user to capture the current register settings within a c/c++ header file as a “#define” list of
register settings. The output file can be used to transfer the current register set-up to user firmware.
I2C (only available when using I2C target products )
The I2C menu is only visible when an I2C-enabled device profile or the generic I2C device profile is selected.
Data Rate
The data rate can be selected from the four standard I2C configurations, supporting standard mode at 100kbps,
fast mode at 400kbps, fast mode plus at 1Mbps, and high-speed mode at 3.4Mbps. The actual options in this
menu will vary depend ing on the m odes that are cur rently su pported, e.g., high-speed m ode is onl y sho wn if it is
supported by the selected profile. Note that when changing to high-speed mode, the high-speed command is
issued when selecting the data rate. This command remains persistent by replacing subsequent stop and start
sequences with restart sequences. To revert to norm al operation, either standard or fast m ode mus t be selec ted
from the menu.
Figure 12. I2C Data Rate Selection
Search I2C Slave
Selecting t he “Search I 2C S l a ve” option wil l star t the process of s ear ching thr ou gh all available 7-bit I2C addresses
to discover any slave devices attached to the I2C bus. The process works by attempting to read register “0” of
each device and testing for a received acknowledgment on each byte of the data packet. When a slave is
discovered − indic ated by a vali d acknowledgem ent on the I2C bus − the “found slave” dialog will be displayed to
indicate the addr es s . Pressing the “OK” button will proceed with the next address and continue the search.
Figure 13. Searching for an I2C Slave Device
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Micrel Serial Programmer (MICUSB) − User Guide
Single-Wire Interface (SWI) (only available when using SWI target products)
The single-wire interface (SWI) menu is only visible when an SWI-enabled device pr of ile is select ed.
Data Rate
The data rate can be selected from five standard communication speeds: 100kHz, 1MHz, 3MHz, 6MHz, and
10MHz. All sp eeds ar e compatible with standard Mic rel SW I -based IC s. Change s to the SWI data r ate take eff ect
immediately and are active from the next communication.
Figure 14. SWI Data Rate Selection
Help
“About”
Selecting A bout f rom the help m enu wil l displa y a general p urpose inf orm ation display showing the version of the
software, the included libraries and support contact information. Note that In the event of any issue or bug, the
user can provide the version number of the GUI and send to Micrel technical support.
Figure 15. Help “About” Information
“User Guide”
Selecting the “User Guide” option from the Help menu will open a local copy of this document on the machine
running the GUI.
Offline Mode/Dire ct Editing Mode
This option is not actually a menu, but pressing this button will switch between Offline Mode and Direct Editing
Mode. The function provides a toggle function for the Link > Link Mode se tting described in the Link Mode sub-
section.
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Micrel Serial Programmer (MICUSB) − User Guide
Generic Operations and Mode
At start-up, and when no device profile is selected, the GUI is operated in Generic Mode. In Generic Mode, a
user-selectable number of registers can be accessed for reading and writing, using a flexible and configurable
interface that allows a large number of operations to be performed. Currently, only I2C Mode is supported in
Generic Mode.
Configuration and Status
Status Bar
At the bottom of the GUI, there is a status bar that reads - from left to right – the following.
• Profile name or part number
• Destination address of the I2C device
• Currently-selected data rate
• Progress bar for status of present operation
• General purpose status message output
During norm al operation, the status of individual I2C commands and communications are displayed in the status
message section of the status bar.
Figure 16. Configuring Basic Interface Communication Settings
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Destina tion Address and Test
The “Destination Address” and “Test” buttons allow the user to enter the 7-bit I2C address in either hexadecimal or
binary, and then tes t whether a device respon ds to a read com mand. Onc e the slave addr es s has b een s e le c ted,
pressing t he T est butto n wil l perfor m a simple read o p eration a nd test t he AC K re sponse to deter m ine if the slave
device responds to the communication. After the test, the status of the operation is displayed in the status bar.
Note that with SWI Mode being write only, the test button has no function and always returns success.
Registe r Configuration
First select the “Registers” tab from the tab list. The number of register s f or readin g and writ ing can b e c onf ig ured
to any number of successive registers starting at any legal 8-bit register address, by modifying the registers
up/do wn count er and t he “Address” register. T he star t addr ess f or the s ucces siv e reg isters c an be enter ed i n the
leftmost “Address” box. Individual registers can be read or written via the “Data” text boxes, in conjunction with
the “Read/Write” buttons or in dir ect editin g mode. The “Read Onl y” c heck boxes c an be use d t o sel ecti vely inhibit
the write commands to individual registers. Note that selecting the “Read Only” checkbox will result in the GUI
ignoring write commands to those addresses.
Figure 17. Communication Register Configuration
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Some examples of several operating modes are shown in Figure 18. The leftm ost image shows a single re gister
being used to program or read from a single address location. The middle image shows three consecutive
writable registers starting at a non-zero address. The rightmost image shows an example for a device with five
registers, of which only the first three are writeable.
Figure 18. Examples of Register Configuration
Reading and Writing Registers
Again, select the “Registers” tab of the tab list. After configuring the register address and range, pressing the
“Read” button will issue I2C command to read all of the registers that are displayed. Once read, the register
contents are displayed in the associated register “Data” text boxes. Any errors will be reported b y the message
status bar at the bottom of the screen.
Register write can be performed in two ways depending on the mode. For bot h modes, the se lected “Data” text
boxes should be updated with the required data to be written entered in hexadecimal format. In direct access
mode, a register write will be issued immediately following t he editing of the data text box, when the enter ke y is
pressed or focus is moved away from the register. If in Offline Mode, pressing the “Write” button in the “Operation”
pane will iss ue the I2C com m ands to perf orm the write of all of the displa yed regist ers, with the except ion of those
where the “Read Only” check boxes are checked. Note that pressing either the “Read” or “Write” button will
perform the operation on all of the registers displayed.
Figure 19. Manually Reading and Writing Registers
Read and Write Details
When reading or writing the I2C registers using the Read/Write commands, each register will read or write as a
single-byte I2C instruction, from the first register to the last. If a read or write operation fails before the final
address, the operation is aborted immediately, a message is displayed, and unread registers are updated to
display a red “XX” pattern.
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Automatic Register Polling
The GUI allows for automatic register polling of up to three non-sequential device registers, with configurable
polling period. The settings are adjustable via the “Register Pollin g” controls inside the “Target Conf ig” tab of the
tab list .
Each of the three “Address” boxes contains a singl e register va lue. To dese lect a register, adj ust its value to “-1”
using the arrows; this will gray out the value to indicate that the register poll function is disabled. If the box
contains a valid register address, that register will be included in the automatic polling and updated periodically.
Period specifies the time between each poll operation, in milliseconds. Global control of the polling function is
configured with the “Enable” checkbox.
Figure 20. Configuring Automatic Register Polling
Support Information
Technical support for the Micrel Serial Programmer (MICUSB) can be found on the Micrel site at:
www.micrel.com/index.php/en/technical-support. Specific support questions can be submitted via:
www.micrel.com/index.php/en/technical-support/contact-technical-support/analog.html.
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MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL +1 (408) 944-0800 FAX +1 (408) 474-10 00 WEB http://www.micrel.com
Micrel makes no representati ons or warranties with respect to the accuracy or completeness of the information furnished in this data sheet.
This information is not intended as a warranty and Micrel does not assume responsibility f or its use. Micrel reserves the right to change
circuitry, specif ic ations and desc ripti ons at any time without notic e. No lic ense, whether express , im plied, arising by estoppel or otherwise, t o
any intellectual property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products,
Micrel assumes no liabilit y whatsoever, a
nd Micrel disclaims any express or implied warranty relati ng t o the sale and/or us e of Micrel products
including liabi l ity or warranties rel ating to fitness for a particular purpose, merchantabilit y, or infringement of any patent, copyright or other
intellect ual property right.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a
product can reasonabl y be expected to result in personal i nj ury. Lif e support devices or systems are devices or systems that (a) are intended
for surgical impl ant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a
significant injury to the user. A Purchaser’s use or sale of Micrel Products for us e in life support appliances, devices or systems is a
Purchaser’s own risk and Purchaser agrees t o fully indemnify Mic rel for any damages resulti ng from such use or sale.
© 2014 Micrel, Incorporated.
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ANTC03 - PCI Express – Signal Integrit y & EMI
Appendix A
Schematics
MICUSB I2C Dongle
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