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www.ti.com Question: Can I use single wires for connection between MSP-GANG and target device? 135 SLAU358Q – September 2011 – Revised October 2019 Submit Documentation Feedback Copyright © 2011–2019, Texas Instruments I…

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Frequently Asked Questions

Chapter 6

SLAU358Q– September 2011 –Revised October 2019

Frequently Asked Questions

6.1 Question: Why does device init, connect, or programming fail?

Answer: Frequently the cause is a bad connection between the MSP-GANG Programmer and the target

device. A 14-wire ribbon cable is provided for JTAG/SBW or BSL connection between MSP-GANG and

target device. The ribbon cable has an impedance of approximately 100 Ω and has DC lines in the ribbon

cable to provide good isolation between signal wires (TDI, TCK, TMS, TDO). Each signal wire is

separated by a DC wire to minimize crosstalk between the signal wires. The following pinout used in the

MSP-GANG on each JTAG connector:

1 - TDO (Signal wire)

2 - Vcc / Vcc sense (DC wire)

3 - TDI (Signal wire)

4 - Vcc sense (DC wire)

5 - TMS (Signal wire)

6 - n/c (DC wire)

7 - TCK (Signal wire)

8 - TEST (DC wire in JTAG)

9 - GND (DC wire)

10 - n/c (DC wire)

11 - RESET (DC wire in JTAG)

12 - BSL-Tx (Signal wire)

13 - n/c (DC wire)

14 - BSL-Rx (Signal wire)

The provided 14-pin connector might not be ideal for some customers who want to minimize the number

of wires and pinout order. When using a custom cable, make sure to address the issue of crosstalk

between signal cables. Unfortunately, in many cases the custom cable does not provide good isolation

between signal wires. As an example of a bad connection, the following uses an 8-wire ribbon cable for

JTAG communication:

1 - Vcc / Vcc sense (DC wire)

2 - TDO (Signal wire)

3 - TDI (Signal wire)

4 - TMS (Signal wire)

5 - TCK (Signal wire)

6 - TEST (DC wire in JTAG)

7 - GND (DC wire)

8 - RESET (DC wire in JTAG)

On this connection, the TMS signal is coupled with the TCK and TDI lines and can generate additional

TCK pulses on the TCK wire (rise time on TMS line can be seen on the TCK line also and can be

detected by the MSP MCU as an additional unexpected TCK pulse).

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Question: Can I use single wires for connection between MSP-GANG and target device?

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Frequently Asked Questions

6.2 Question: Can I use single wires for connection between MSP-GANG and target device?

Answer: Single wires are a poor type of connection and provide very bad quality. Single wires work like

inductors connected between the MSP-GANG and target device, generating ripples on the target device

side. If a ribbon cable cannot be used, then a twisted-pairs connection should be used instead. One wire

on each twisted pair should be connected to a signal connection (for example, TDI or TCK), and the

second wire connected to DC (GND or V

) from both sides of the connection (one on the MSP-GANG

side and the other on the target device side). For example, the following arrangement is acceptable:

1 - TDO (Signal wire) - first twisted pair

1 - Vcc / Vcc sense (DC wire)

2 - TDI (Signal wire) - second twisted pair

2 - Vcc sense (DC wire)

3 - TMS (Signal wire) - third twisted pair

3 - RESET (DC wire)

4 - TCK (Signal wire) - fourth twisted pair

4 - GND (DC wire)

If additional protecting components (such as a capacitor or suppressors) are used on the target device

PCB, check the JTAG signal shape on the MSP MCU. The JTAG communication speed should be

decreased (set to medium or slow) if required. Make sure that any ripple on the JTAG lines is smaller than

20% of the peak-to-peak signal level.

If connection cables are longer than 40 cm, then the ripple can be reduced by inserting 33-Ω resistors in

series with TCK, TMS, and TDO in the middle of the connection wires. Do not provide series resistors in

TEST and TDI lines if the device will be secured (blown the security fuse) for MSP families 1xx, 2xx, and

4xx. For blowing the security fuse in these devices, the programmer provides Vpp 6.5 V at 100 mA on the

TEST or TDI lines to MSP MCU. An additional resistor inserted in these lines can reduce the maximum

current provided to the MCU and the security fuse will not be blown.

6.3 Question: How to serialize parts?

Answer: The MSP-GANG GUI does not provide serialization; however, the provided MSP-GANG.dll allows

to program unique data (for example, calibration or serialization) to each target device. An example to

implement serialization using MSP-GANG.dll is available in this directory:

C:\Program Files (x86)\Texas Instruments\MSP-GANG\Examples\CPP_Applications_MSP_DLL

6.4 Question: How to have parts run after programming?

Answer: By default in the MSP-GANG Programmer, the RESET line is forced to low level, which prevents

the target device running after being programmed. But that option can be modified using the pulldown

menu:

• Setup > Finish Action

and selecting one of the options:

• Hardware reset (RST line) and start the application program

• OFF/ON the V

and start the application program

Application Program Run time is programmable from 1 to 120 seconds or infinite time.

6.5 Question: What are possible reasons for the part to fail Verify step?

Answer: If the part was programmed and verified in the GO step, and after the second time the Verify step

failed, then in most cases the firmware is modifying flash contents when running for the first time. Usually

the Info memory is modified in that case. Ask your software team if the firmware downloaded to the MCU

is modifying the flash after the first run. If that is the case, then the firmware should be modified to contain

only unmodified contents in the code file. To compare the code file contents and flash data (if modified),

use this option from the pulldown menu:

• View > Compare Code File and Flash Data

Revision History

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136

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Revision History

NOTE: Page numbers for previous revisions may differ from page numbers in the current version.

Changes from February 23, 2019 to October 8, 2019 ..................................................................................................... Page

• Removed CISPR 24: 2010 / EN 55024:2010 and added CISPR 32:2012 / EN55032:2012/AC:2013 and related warning in

the CE section of FCC and CE Compliance........................................................................................... 8

• Rev M - section 3.2.1 changed RSS-210 or RSS-247 ............................................................................ 137

• Rev O - Added WARNING in section 2.3 ........................................................................................... 137