Points/Wires Basic Info

[maplegsm]

Points/Wires info
Name
Function
Connections

VCC
Power - Supplies VCC (5 V, 10 mA, typically) to the cable.
To target system VCC

GND
Ground - Supplies ground reference to the cable.
To target system ground

TCK
Test Clock - Drives the test logic for all devices on a JTAG chain.
Connect to system TCK pin.

TDO
Test Data Output - data from the target system is read at this pin.
Connect to system TDO pin.

TDI
Test Data Input - this signal is used to transmit serial test instructions and data.
Connect to system TDI pin.

TMS
Test Mode Select - this signal is decoded by the JTAG state machine to control test operations.
Connect to system TMS pin.


Note TRST is an optional pin in the JTAG (IEEE 1149.1) specification, and is not used by XC9500 CPLDs. If any of your non-Xilinx parts have a TRST pin, the pin should be connected to VCC.



Bye
UMER

[Albun]

Originally Posted by maplegsm

VCC
Power - Supplies VCC (5 V, 10 mA, typically) to the cable.
To target system VCC
UMER

Wrong. VCC direction is not to target system, but FROM target system.
DO NOT CONNECT POWER TO YOUR TARGET BOARD USING VCC PIN. IT IS MOST LIKELY YOU WILL KILL THE DEVICE!!!

VCC is used by most JTAG devices to adjust their I/O voltage levels to target ones. It has nothing to do with JTAG device power supply, it only powers logic translation buffer chip. Most often JTAG logic voltage levels are 1.8V, 2.6V and 3.3V

RIFFBOX does not require this signal to be connected. It uses internal DAC
to setup JTAG I/O voltage as required.

[maplegsm]

Originally Posted by Albun

Wrong. VCC direction is not to target system, but FROM target system.
DO NOT CONNECT POWER TO YOUR TARGET BOARD USING VCC PIN. IT IS MOST LIKELY YOU WILL KILL THE DEVICE!!!

VCC is used by most JTAG devices to adjust their I/O voltage levels to target ones. It has nothing to do with JTAG device power supply, it only powers logic translation buffer chip. Most often JTAG logic voltage levels are 1.8V, 2.6V and 3.3V

RIFFBOX does not require this signal to be connected. It uses internal DAC
to setup JTAG I/O voltage as required.

I Posted Just Short Info For Beginner I Know Jtag Voltage Levels
I Think You are Thinking That 5V Will Kill The Set , I Think Not
If Riffbox Does not Requires This Signal Than Moderators Will Edit Info


Bye
UMER