Hi,
My customer started to evaluate the LMK04208 on EVM with user's guide.
However they can not program to EVM.
Looking into USB2ANY, uWire signal(J4-9, J4-8, J4-7) and 3.3VEXT(J4-6pin) are not outputted.
Status LED is lighting and TICS PRO is recognizing USB2ANY.
What should we do to solve this problem?
Best Regards,
Kuramochi
Hi,
I have an additional information.
MSP430 doesn't pull up "EXT3.3V EN".
Is this correct behavior?
Best Regards,
Kuramochi
Hello Kuramochi,
I apologize for the long delay.
External 3.3V on USB2ANY is not used by this device, so EXT3.3V_EN low is okay.
Just to confirm, they are applying 4.5-5V to the VCC pin for the EVM, correct? The device may not work properly if 3.3V is applied to VCC (the LDO will be in dropout at around 3V), which can look like a programming issue.
To quickly check communications, set the POWERDOWN bit in TICS Pro and observe the power supply output current; a successful programming will substantially decrease device current consumption. I recommend this check first, because it separates register configuration issues from device communication issues. There are some register settings that can look like the device cannot be programmed, like RESET bit set or incorrect SYNC settings. If programming the POWERDOWN bit does decrease the current consumption substantially, I need the .tcs file from TICS Pro that they are trying to load into the device. If programming the POWERDOWN bit does not decrease the current consumption substantially, the following instructions will help debug the hardware interface:
uWire signal on the LMK04208EVM is sent on pins 8, 4, 2 of the uWire header, so these pins should be checked for signal. First, confirm that R44, R48, and R54 are populated. Also, R45, R49, and R55 should not be populated, and C41, C42, and C43 should not be populated. After confirming these components, connect an oscilloscope probe to the LE, CLK, and DATA test points, set the trigger polarity to LE falling edge, and confirm whether uWire transactions generate a signal on these pins. To generate uWire transactions, change any register value in TICS Pro or push Ctrl+L to write all registers.
If uWire signals are not present, it is possible the uWire bus is somehow overloaded or shorted to GND/VCC. Try removing R44/R48/R54 and monitoring uWire pins 8/4/2 directly. Alternately, plug in free-floating header pins or wires to the USB2ANY cable uWire signals corresponding to pins 8/4/2 of the uWire header, and monitor the signals with an oscilloscope. If you still see no signals after this point, the USB2ANY is defective.
If the uWire signals are present, check if the device RESET pin is forced high, or if the RESET bit is set in software.
Let me know if there are still programming issues after trying these debugging steps.
Regards,
