What is the power supply tolerance for the Netburner modules?
My design, because of the resistor range available means I am only getting 3.256V from the regulator but the voltage is very stable and clean.
Is this enough for the Netburner to function correctly? I can't find anything in the documenation about this.
When I plug in the Ethernet, I get the LED's coming on and the activity LED is flashing but I don't seem to get any debug output and it can not find it from Eclipse.
Other testing being done to make sure is nothing else at fault.
Cheers,
Dave...
Power supply tolerance
Re: Power supply tolerance
Re:" ... and it can not find it from Eclipse"
Those pronouns and their pesky antecedents. I assume the 2nd "it" means the NetBurner and not the debug output. Can you see the NetBurner from IpSetup or AutoUpdate? With the serial port attached do you see the monitor boot message? The one time I was involved with a project that starved the input voltage the NetBurner would reset, but as I recall we had momentary fluctuations that dragged the input down to (and slightly below) the 3.0v range when it happened. I would assume (but hey I'm a software guy) the minimum input voltage might vary by chip, the 5272 for example is spec'd at 3.0-3.6 V.
Those pronouns and their pesky antecedents. I assume the 2nd "it" means the NetBurner and not the debug output. Can you see the NetBurner from IpSetup or AutoUpdate? With the serial port attached do you see the monitor boot message? The one time I was involved with a project that starved the input voltage the NetBurner would reset, but as I recall we had momentary fluctuations that dragged the input down to (and slightly below) the 3.0v range when it happened. I would assume (but hey I'm a software guy) the minimum input voltage might vary by chip, the 5272 for example is spec'd at 3.0-3.6 V.
Re: Power supply tolerance
+/- 5% should be ok.
I would connect a scope to the UART0 TX signal and look for serial data, then check on the other side of your level shifter.
I would connect a scope to the UART0 TX signal and look for serial data, then check on the other side of your level shifter.
Re: Power supply tolerance
Thanks guys,
The supply looks OK so I suspect something else. The design is new but based on a previous design so I am bit stumped to why there is no UART0 output either.
@rnixon, I checked the UART0 output and there is no data going into the RS232 driver (MAX3232). Output is permanently high. I don't have the CTS0 connected on this board, or the previous board and I assume that debug does not require handhshaking to be enabled? I am not using them on the other board so I suspect not.
If I put the MOD5234 back in the dev board I get UART output and it runs!!
@tod. I was referring to the SCAN for Netburner modules within Eclipse. The supply is stable and there is no dips detected on the scope.
The supply looks OK so I suspect something else. The design is new but based on a previous design so I am bit stumped to why there is no UART0 output either.
@rnixon, I checked the UART0 output and there is no data going into the RS232 driver (MAX3232). Output is permanently high. I don't have the CTS0 connected on this board, or the previous board and I assume that debug does not require handhshaking to be enabled? I am not using them on the other board so I suspect not.
If I put the MOD5234 back in the dev board I get UART output and it runs!!
@tod. I was referring to the SCAN for Netburner modules within Eclipse. The supply is stable and there is no dips detected on the scope.
Re: Power supply tolerance
My next guess is that this is not a serial problem, rather the module is not booting at all. Many possible causes. Look at the reset line, and anything that might fight with the data bus.
Re: Power supply tolerance
The reset line is OK.
The databus is connected to an SN74LVT16245BDL bus transciever as per my other design and same as on the dev board.
I have checked for shorts on the databus and all appears to be good. Will have a good look over the board tomorrow though to be sure and scope the databus to see if I can detect something strange. Must be something the same as I have 2 prototype boards and both are doing this!!
Thanks
Dave...
The databus is connected to an SN74LVT16245BDL bus transciever as per my other design and same as on the dev board.
I have checked for shorts on the databus and all appears to be good. Will have a good look over the board tomorrow though to be sure and scope the databus to see if I can detect something strange. Must be something the same as I have 2 prototype boards and both are doing this!!
Thanks
Dave...
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Ridgeglider
- Posts: 513
- Joined: Sat Apr 26, 2008 7:14 am
Re: Power supply tolerance
I'll bet that on the module that runs you may have altered the default serial port in the setup screen that is available w/ the "A" in the first few seconds of booting? Try seeing if the setup parameters for the COM ports on the working and non-working modules are the same.
Re: Power supply tolerance
A stable 3.256V will definitely be OK, +-5% is well within the range of all the components. How much current is the supply rated for?
Check the clock out signal to see if it is at the proper frequency (~75MHz). This will confirm that the boot monitor initialization ran, otherwise you will see a lower frequency which is the PLL default. If the frequency is lower then ensure that there is nothing connected to the data bus. Since you used a SN74LVT16245BDL this should be simple, just fix the enable line so it is not asserted. After you isolate the bus see if you now boot with the proper frequency.
Check the clock out signal to see if it is at the proper frequency (~75MHz). This will confirm that the boot monitor initialization ran, otherwise you will see a lower frequency which is the PLL default. If the frequency is lower then ensure that there is nothing connected to the data bus. Since you used a SN74LVT16245BDL this should be simple, just fix the enable line so it is not asserted. After you isolate the bus see if you now boot with the proper frequency.
Re: Power supply tolerance
You should also look at the TA signal to make sure that isn't being pulled/held low; this was a problem I had, and it results in hanging the processor. You will also see an unusual clock frequency, as Larry mentions.
You might want to look at this: http://forum.embeddedethernet.com/viewt ... &sk=t&sd=a or search for "Custom board for PK-70 hangs processor - funny clock?" in this forum for my post and Larry's responses.
HTH
Bob...
You might want to look at this: http://forum.embeddedethernet.com/viewt ... &sk=t&sd=a or search for "Custom board for PK-70 hangs processor - funny clock?" in this forum for my post and Larry's responses.
HTH
Bob...
Re: Power supply tolerance
Hi All,
I got the board working. Sort of. There was a short on the 0.5mm pitch connector to the LCD board on one of the databus lines. Both boards the same issue but different pins. These where the only 2 connectors soldered by hand. The rest of the board was done with reflow.!! Typical!!
I can programme and debug it over Ethernet but I am still not getting any debug output on UART0 for some reason. The circuit I am using with the MAX3232 is identical to the one on my other design and it is outputting data.
I assume that handkshaking is ignored in the OS for this UART?
I have checked the wiring and the it is fine. No shorts to VCC or GND.
Very puzzling but I am not giving up!!
)
Dave...
I got the board working. Sort of. There was a short on the 0.5mm pitch connector to the LCD board on one of the databus lines. Both boards the same issue but different pins. These where the only 2 connectors soldered by hand. The rest of the board was done with reflow.!! Typical!!
I can programme and debug it over Ethernet but I am still not getting any debug output on UART0 for some reason. The circuit I am using with the MAX3232 is identical to the one on my other design and it is outputting data.
I assume that handkshaking is ignored in the OS for this UART?
I have checked the wiring and the it is fine. No shorts to VCC or GND.
Very puzzling but I am not giving up!!
)Dave...