GOWIN GWU2X Operating instructions

GWU2X Programming Guide_U2X_JTAG
UG1003-1.0E, 06/29/2021

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Revision History
Date
Version
Description
06/29/2021
1.0E
Initial version published.

Contents
UG1003-1.0E
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Contents
Contents............................................................................................................... i
List of Tables....................................................................................................... ii
1 General Description ........................................................................................ 1
2 Programming................................................................................................... 5
2.1 API Functions...................................................................................................................... 5
2.1.1 Get JTAG Status.............................................................................................................. 5
2.1.2 Get Running Error Information ........................................................................................ 5
2.1.3 Generate TMS Signal Array............................................................................................. 6
2.1.4 Set TCK Frequency......................................................................................................... 6
2.1.5 Set IO Ports..................................................................................................................... 7
2.1.6 JTAG Status Reset.......................................................................................................... 7
2.1.7 JTAG Status Jumping to IDLE......................................................................................... 8
2.1.8 Send IR Data................................................................................................................... 9
2.1.9 Send DR Data................................................................................................................ 10
2.1.10 Readback TDO Data ....................................................................................................11
2.1.11 Generate Commands to Send DR Data.......................................................................11
2.2 Programming Example.....................................................................................................12
Terminology and Abbreviations...................................................................... 16
Support and Feedback..................................................................................... 17

List of Tables
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List of Tables
Table A-1 Terminology and Abbreviations.......................................................................................... 16

1 General Description
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1General Description
GWU2X can be used to create a USB to JTAG protocol interface to
read/write JTAG interfaces. Its TCK clock frequency can be configured. It
supports up to 15MHz TCK according to the current test result. It can send
or read IR/DR data of any BIT length.

2 Driver Installation and Uninstallation
2.1 Use Zadig to Install Driver
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2Driver Installation and Uninstallation
GWU2X _JTAG can be programmed using libusb, the open source
USB function library. To program with this function library, the “WinUSB.sys”
USB driver program needs to be installed.
You can use Zadig(https://zadig.akeo.ie/), the open source driver
installation tool, to install driver. The driver installation requires administrator
privileges.
2.1 Use Zadig to Install Driver
Connect GWU2X device to the computer USB interface, double-click to
open Zadig (administrator privileges required), click Options, and check the
"List All Device" option. All USB devices connected to the computer will be
listed.
Figure 2-1 Check “List All Device” Option
Select GWU2X, the device that requires driver installation.

2 Driver Installation and Uninstallation
2.1 Use Zadig to Install Driver
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Figure 2-2 Select the Device that Requires Driver Installation
Select the driver to be installed, use libusb+WinUSB, and select
WinUSB.
Figure 2-3 Select the Driver Program to be Installed
Click “Install Driver”. The driver will be installed after a few moments.
Note!
The button displays "Install Driver" if the driver is not currently installed, and "Replace
Driver" if another driver is currently installed.

2 Driver Installation and Uninstallation
2.2 Uninstall Driver
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2.2 Uninstall Driver
To uninstall the driver, connect GWU2X device to the computer, open
the windows device manager, and find GWU2X device in the "Universal
Serial Bus Devices" list. Right-click on the device name and select the
"Uninstall Device" option in the pop-up menu.
Figure 2-4 Open Device Manager
In the pop-up dialog box, first check "Remove driver software for this
device", and then click the “Uninstall” button to uninstall the driver.
Figure 2-5 Uninstall Device

3 Programming
3.1 API Functions
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3Programming
3.1 API Functions
3.1.1 Get JTAG Status
const char * jtag_get_state_str(int iJtagStateCode);
Parameters:
iJtagStateCode: A variable of the JTAG state. For the variable definition,
please refer to the enumerated value of JTAG_STATE defined in
gw_usb2jtag.h.
Return Value:
A const char pointer to the address of a string that describes JTAG
status. It can be used to output information for debugging.
3.1.2 Get Running Error Information
const char * usb2jtag_get_err_info(int errCode);
Parameters:
errCode: Returns the error code ofAPI functions. Returns 0 if
successful; returns a negative value if an error occurs in the function
running.
Return Value:
A const char pointer to the address of a string that describes error
Information. It can be used to output information for debugging.