CCS/MSP430F5529: MSP430F5529LP Program via Spy-Bi-Wire

Hey Vincent,

Could you please provide your schematic and a picture of your test setup so that I can look into your issue further?

Best regards,

Matt

Are you certain the MCU is correctly soldered onto your PCB?  The SBW lines may not be properly connected to the device. Check for solder bridges. This footprint is a challenge for non-machine assembly.  I have made prototype boards with the smaller F5528 using a paste stencil and reflow soldering. 

Hi Matt

Let me attach setup photo and parts of our schematic.

Full setup.  Both the LP and our PCB are correctly powered.

Our MCU PCB; we use MSP430F5519.  The PCB is designed for USB Powered.  However, for debug purpose, we soldered the grey wire so that we power it by the 3V3 jumper on the launchpad.

The white plastic cover contains pin 71 ~ 76 and the BSL pin.

Part of MCU schematic, we basically just copy the schematic of MSP430F5529LP. 

Thank you

Hi Matt

Add two comments.

When opening target configuration file in CCS 8.3.1, the "Test Connection" button is greyed out.

While when I doing other MSP432R401 projects, I often use "Test Connection" to confirm the debug probe and connection are good.

I'm new to MSP430 and not sure if this is correct.

As for solder and contact issue, I have three identical PCBs, none of them is programmable.  I suppose soldering is not the cause.

Regards

Vincent

Vincent,

I can easily see that you are correctly connecting the SBWRST and SBWTST signals from the eZ-FET circuitry to the headers on your board, but the rest of the signal connections are difficult to see. Could you explain or show more clearly where you are properly connecting the power and GND lines?

In general, the shorter the wires are connecting the 2 board together, the better. Voltage drops and parasitic capacitance can lead to programming errors so I would try to keep those wires as short as possible.

Best regards,

Matt

Hi Matt

I connect 4 pins between the launchpad and my PCB: GND, 3V3, SBWRST, SBWTST.  I used a 4-pin ribbon cable to connect SBWRST and SBWTST.  The unconnected two pins are out of focus and confuses you.  Actually they are NC. 

The 3V3 is connected between EZFET_VCC and PCB VCC; GND is also corrected shared between the lauchpad and the PCB.  I measured the voltage of my PCB, the VCC is about 3.29V; I suppose it it OK.  Disconnect the 3V3 connection and power my PCB via USB_VBUS doesn't change the situation, CCS still cannot recognize the MSP5519 and returns me "unknown device".

Regards

Vincent,

It looks like Mike was able to reproduce your issue and validate a solution based on my previous recommendation. Please let us know if you are able to solve this on your end as well.

Best regards,

Matt

Hi Matt, Mike

Thank you for providing the information.  Unfortunately, nothing changes after replacing the SBWTCK and SBWTDIO cable with a short one ( < 15cm length).

On the other hands, I partially solve my problem but don't know the reason behind it.

I hooked a oscilloscope probe to SBWTDIO to check the signal with a scope.  When a passive scope probe is attached, CCS could program my MSP5519 via the ezFET emulator.

I suppose it it due to the parallel capacitance of the probe.  Based on page 22 of  slau278 http://www.ti.com/lit/ug/slau278af/slau278af.pdf , it recommends an 1.1nF capacitance (C1 in the figure below) between SBWtDIO and GND. My PCB doesn't have this capacitance, I guess the passive scope probe provides this capacitance.  My probe is a SP200B http://www.ni.com/pdf/dspdf/en/ds-437 by National Instruments, which has 100pF capacitance.

After that, I unhooked the probe, soldered an 1nF capacitance like the following figure.  However, CCS and the launchpad still cannot recognize the modified PCB unless the scope probe is attached.

I have no idea about it and will try other capacitance value or scope probes.

Regards

Vincent,

I does look like you are narrowing down the root cause of the issue here. Moving forward, it is best to keep all fly wire connections the same length and as short at possible to reduce the chances of device miscommunication.

In your case, it looks like the capacitance on the RST line (SBWTDIO) is causing the inability to recognize the device. According to that hardware tools user's guide you referenced: "The range for C1 can vary between 0.1 nF and 2.2 nF depending on SBW speed, voltage, and board design." The capacitor used on our Launchpad is selected for that specific board design and you may need to tweak it based on your setup; especially taking into account that you are trying to use jumper wires for testing.

Best regards,

Matt