what does JTAG mean? (newbie)

[grasssu]

When I was reading posts here, I always found a word JTAG. What does it mean? Thanks!

[MaxmMhz]

A Jtag is a piece of equipment used to read the chip/chips called the Tsop on a reciever motherboard. It will allow you to rewrite the firmware for the reciever after you have modified it or if you just want to replace it after an ECM (Electronic CounterMeasure) which is what the Satellite Distributor uses to combat Piracy.

[grasssu]

Thanks for your explanation! Do different receivers use different Jtags? E.g.I'm using a pansat 2700 receiver, what kind of Jtag should I buy?

Thanks again!

[dellsam34]

JTAG means Junior Tits Are Guns, Most of FTA receivers are FTP modified you don't have to mess with the hardware, they are much easier than Dicknetwork equipment.

[Ohms]

You can build a simple jtag out of easy to get parts from Radio Shack for about $5 or less. Just solder it into the 2700. Works great.

I use a simple jtag, but used to use a buffered jtag. Both will work.

buffered jtag: Http://bellexpress.vu/forum/local_links.php?action=jump&id=68&catid=47

I have not found my old plans for the simple jtag, and searched the file section here and did not find them either. I suggest you look around and find the plans for the simple jtag as this is working on everything right now and is super easy to build.

[dellsam34]

You can build a simple jtag out of easy to get parts from Radio Shack for about $5 or less. Just solder it into the 2700. Works great.

I use a simple jtag, but used to use a buffered jtag. Both will work.

buffered jtag: Http://bellexpress.vu/forum/local_links.php?action=jump&id=68&catid=47

I have not found my old plans for the simple jtag, and searched the file section here and did not find them either. I suggest you look around and find the plans for the simple jtag as this is working on everything right now and is super easy to build.

That's a lot of work for a lazy like me, thank god I have DG Station Relook 400S so I don't have to get up from my sofa at all, all done by wireless FTP and remote control.

[SuperManny]

You can build a simple jtag out of easy to get parts from Radio Shack for about $5 or less. I have not found my old plans for the simple jtag, and searched the file section here and did not find them either.I uploaded one to the files section under TSOP Utilities.:D
http://bellexpress.vu/forum/local_links.php?action=jump&id=742&catid=27

[jamrock1]

simple J-Tag parts list
(1).male Db 25 raw
(2.)4 100 ohm resistor 1/4 watt oor 1/2 watt
(3).1 22k ohm resistor
(4) ribbon wire

pins 2,3,4,5 gets 100 ohm resistor and pin 13 gets 22k ohm
pins 18-25 gets tied together and works as ground

all parts available at ratshack

[skinerd]

Joint Test Action Group (JTAG) is the usual name used for the IEEE 1149.1 standard entitled Standard Test Access Port and Boundary-Scan Architecture for test access ports used for testing printed circuit boards using boundary scan.

JTAG was an industry group formed in 1985 to develop a method to test populated circuit boards after manufacture. At the time, multi-layer boards and non-lead-frame ICs were becoming standard and making connections between ICs not available to probes. The majority of manufacturing and field faults in circuit boards were due to solder joints on the boards, imperfections in board connections, or the bonds and bond wires from IC pads to pin lead frames. JTAG was meant to provide a pins-out view from one IC pad to another so all these faults could be discovered. The industry standard finally became an IEEE standard in 1990 as IEEE Std. 1149.1-1990 after many years of initial use. That same year Intel released the first processor with JTAG: the 80486 which led to quicker industry adoption by all manufacturers. In 1994, a supplement that contains a description of the boundary scan description language (BSDL) was added. Since then, this standard has been adopted by electronics companies all over the world. Boundary-scan is nowadays mostly synonymous with JTAG.

While designed for printed circuit boards, JTAG is nowadays primarily used for accessing sub-blocks of integrated circuits, and is also useful as a mechanism for debugging embedded systems, providing a convenient "back door" into the system. When used as a debugging tool, an in-circuit emulator - which in turn uses JTAG as the transport mechanism - enables a programmer to access an on-chip debug module which is integrated into the CPU, via the JTAG interface. The debug module enables the programmer to debug the software of an embedded system.

In most ICs today, all internal registers are on one of many scan chains. This allows all combinational logic to be tested completely even while an IC is in the circuit card and possibly while in a functioning system. When combined with BIST, the JTAG scan chain enables a low overhead, completely embedded solution to testing an IC for certain static faults (shorts, opens, and logic errors). The scan chain mechanism does not generally help diagnose or test for timing, temperature or other dynamic operational errors that may occur.

[skinerd]

simple J-Tag parts list
(1).male Db 25 raw
(2.)4 100 ohm resistor 1/4 watt oor 1/2 watt
(3).1 22k ohm resistor
(4) ribbon wire
pins 2,3,4,5 gets 100 ohm resistor and pin 13 gets 22k ohm
pins 18-25 gets tied together and works as ground
all parts available at ratshack


I use 150 or 180 ohm resistors for all 5 pins, never a problem.

[grasssu]

Sorry, what is DG Station Relook 400S used for?
That's a lot of work for a lazy like me, thank god I have DG Station Relook 400S so I don't have to get up from my sofa at all, all done by wireless FTP and remote control.

[grasssu]

Thank you guys! So after I build my simple JTAG, how do I connect it to my pansat 2700 and then update its firmware? And where can I find the newest firmwares?

[skinerd]

Sorry, what is DG Station Relook 400S used for?

Product Information
The Relook 400S receiver provides digital free-to-air


wonderful thing that google.........just wonderful..........