Tornado is in a better spot to answer that than I am. There may be more standardization of drivers than I think there is. I have little experience to draw from...
Joined: 07 Jun 2006 Posts: 1476 Location: New York, USA
Posted: Thu Mar 26, 2009 22:53 Post subject:
tcharron wrote:
Tornado is in a better spot to answer that than I am. There may be more standardization of drivers than I think there is. I have little experience to draw from...
I sent tornado an email offering my help - the device I have comes with developers software - I offered that to him as well as any testing I can do.
Joined: 07 Jun 2006 Posts: 1476 Location: New York, USA
Posted: Sun Mar 29, 2009 20:27 Post subject:
ewehrer wrote:
These are my exact thought, I do hope a USB JTAG will work.
The device came this weekend - have not had a chance - but I am wondering if with the included sofware, it will recognize the standard JTAG interface and display the output from the interface - will keep everyone posted..
Does anyone know if Tornados software/driver is anything more than a charcter based i/o driver for the paralel interface?
From what i am reading, the board level JTAG is standard - that with this device I should be able to plug it in and see the "mornal" board level output from my router.....
MIPS has their own version of JTAG (called EJTAG) which differs slightly in commands and sequences from the original JTAG standard so don't expect too much from the included software.
There is little if anything to choose between when it comes to USB software for EJTAG, URJTAG is the only free software I have found that support MIPS cpu's and EJTAG. You may have to edit the port pin assignment in the source to match your adapter.
Joined: 07 Jun 2006 Posts: 1476 Location: New York, USA
Posted: Mon Mar 30, 2009 13:26 Post subject:
LOM wrote:
MIPS has their own version of JTAG (called EJTAG) which differs slightly in commands and sequences from the original JTAG standard so don't expect too much from the included software.
There is little if anything to choose between when it comes to USB software for EJTAG, URJTAG is the only free software I have found that support MIPS cpu's and EJTAG. You may have to edit the port pin assignment in the source to match your adapter.
I checked the pin outs/signal for the adapter - it matches the 6 pin header no issues there
Sent a note to the vendor regarding EJTAG and MIPS processor support
I checked the pin outs/signal for the adapter - it matches the 6 pin header no issues there
Sent a note to the vendor regarding EJTAG and MIPS processor support
Ok, that was not exactly what I meant.
Almost all of these USB JTAG devices are based on
a USB -> Serial converter from FTDI and that chip can run in 2 modes.
Either as a RS-232 serial port with all handshake signals or in bit-bang mode where you have full control over each pin and can set them as inputs or outputs, similar to a computer parallel port.
There are around 10 port pins available in that mode and there is not much of a standard for assigning a certain port pin to a certain JTAG pin.
The closest we come to a standard is when a vendor says that his USB-JTAG is OpenOCD compatible but there are a lot of vendors who aren't and who are providing their own program instead.
I guess what I wanted to say is that you can't just buy any USB-JTAG adapter and expect it to function with all USB JTAG softwares.
Joined: 07 Jun 2006 Posts: 1476 Location: New York, USA
Posted: Mon Mar 30, 2009 15:04 Post subject:
LOM wrote:
dellsweig wrote:
I checked the pin outs/signal for the adapter - it matches the 6 pin header no issues there
Sent a note to the vendor regarding EJTAG and MIPS processor support
Ok, that was not exactly what I meant.
Almost all of these USB JTAG devices are based on
a USB -> Serial converter from FTDI and that chip can run in 2 modes.
Either as a RS-232 serial port with all handshake signals or in bit-bang mode where you have full control over each pin and can set them as inputs or outputs, similar to a computer parallel port.
There are around 10 port pins available in that mode and there is not much of a standard for assigning a certain port pin to a certain JTAG pin.
The closest we come to a standard is when a vendor says that his USB-JTAG is OpenOCD compatible but there are a lot of vendors who aren't and who are providing their own program instead.
I guess what I wanted to say is that you can't just buy any USB-JTAG adapter and expect it to function with all USB JTAG softwares.
LOM
This is the one I am looking at (already bought one)
That BlackCAT-USB looks interesting and you can probably use it for flashing a Linksys router.
The cable modems for which it is intended are Broadcomm MIPS based.
This design is not based on a FTDI USB chip, instead it has a programmable Atmel AVR cpu for USB -> JTAG conversion.
The software provided with it has cable modem specific menu items in a similar way as Tornado's software has Linksys specific switches.
The BlackCAT is USD 39.95 but can be had for USD 20.00 !! when bought in 10-pack.
That BlackCAT-USB looks interesting and you can probably use it for flashing a Linksys router.
The cable modems for which it is intended are Broadcomm MIPS based.
This design is not based on a FTDI USB chip, instead it has a programmable Atmel AVR cpu for USB -> JTAG conversion.
The software provided with it has cable modem specific menu items in a similar way as Tornado's software has Linksys specific switches.
The BlackCAT is USD 39.95 but can be had for USD 20.00 !! when bought in 10-pack.
So i'll need the software made just for this...right because the cable modem version is not he same.
You can probably program the flash chip in your Linksys router with the cable modem software by setting up address ranges manually but I haven't seen the software in action so it is hard to give a definite answer.
It would be nice if Tornado decided to include USB devices in tjtag and selected a device like this which
can be had cheap.
