SLAU320AJ July   2010  – May 2021

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 About This Document
    2. 1.2 Organization of This Document
  3. 2Programming Using the JTAG Interface
    1. 2.1 Introduction
      1. 2.1.1 MSP430 JTAG Restrictions (Noncompliance With IEEE Std 1149.1)
      2. 2.1.2 TAP Controller State Machine
    2. 2.2 Interface and Instructions
      1. 2.2.1 JTAG Interface Signals
        1. 2.2.1.1 Pros and Cons of 2-Wire Spy-Bi-Wire and 4-Wire JTAG
        2. 2.2.1.2 4-Wire JTAG Interface
        3. 2.2.1.3 2-Wire Spy-Bi-Wire (SBW) JTAG Interface
      2. 2.2.2 JTAG Access Macros
        1. 2.2.2.1 Macros for 4-Wire JTAG Interface
          1. 2.2.2.1.1 IR_SHIFT (8-Bit Instruction)
          2. 2.2.2.1.2 DR_SHIFT16 (16-Bit Data)
          3. 2.2.2.1.3 DR_SHIFT20 (20-Bit Address) (Applies Only to MSP430X Devices)
          4. 2.2.2.1.4 MsDelay (Time)
          5. 2.2.2.1.5 SetTCLK
          6. 2.2.2.1.6 ClrTCLK
        2. 2.2.2.2 Macros for Spy-Bi-Wire (SBW) Interface
      3. 2.2.3 Spy-Bi-Wire (SBW) Timing and Control
        1. 2.2.3.1 Basic Timing
        2. 2.2.3.2 TMS Slot
          1. 2.2.3.2.1 TMSH Macro
          2. 2.2.3.2.2 TMSL Macro
          3. 2.2.3.2.3 TMSLDH Macro
        3. 2.2.3.3 TDI Slot
          1. 2.2.3.3.1 TDIH Macro
          2. 2.2.3.3.2 TDIL Macro
        4. 2.2.3.4 TDO Slot
          1. 2.2.3.4.1 TDO_RD Macro
          2. 2.2.3.4.2 TDOsbw Macro (No Read)
        5. 2.2.3.5 TCLK Handling in Spy-Bi-Wire (SBW) Mode
          1. 2.2.3.5.1 SetTCLK and ClrTCLK
          2. 2.2.3.5.2 TCLK Strobes
      4. 2.2.4 JTAG Communication Instructions
        1. 2.2.4.1 Controlling the Memory Address Bus (MAB)
          1. 2.2.4.1.1 IR_ADDR_16BIT
          2. 2.2.4.1.2 IR_ADDR_CAPTURE
        2. 2.2.4.2 Controlling the Memory Data Bus (MDB)
          1. 2.2.4.2.1 IR_DATA_TO_ADDR
          2. 2.2.4.2.2 IR_DATA_16BIT
          3. 2.2.4.2.3 IR_DATA_QUICK
          4. 2.2.4.2.4 IR_BYPASS
        3. 2.2.4.3 Controlling the CPU
          1. 2.2.4.3.1 IR_CNTRL_SIG_16BIT
          2. 2.2.4.3.2 IR_CNTRL_SIG_CAPTURE
          3. 2.2.4.3.3 IR_CNTRL_SIG_RELEASE
        4. 2.2.4.4 Memory Verification by Pseudo Signature Analysis (PSA)
          1. 2.2.4.4.1 IR_DATA_PSA
          2. 2.2.4.4.2 IR_SHIFT_OUT_PSA
        5. 2.2.4.5 JTAG Access Security Fuse Programming
          1. 2.2.4.5.1 IR_PREPARE_BLOW
          2. 2.2.4.5.2 IR_EX_BLOW
    3. 2.3 Memory Programming Control Sequences
      1. 2.3.1 Start-Up
        1. 2.3.1.1 Enable JTAG Access
        2. 2.3.1.2 Fuse Check and Reset of the JTAG State Machine (TAP Controller)
      2. 2.3.2 General Device (CPU) Control Functions
        1. 2.3.2.1 Function Reference for 1xx, 2xx, 4xx Families
          1. 2.3.2.1.1 Taking the CPU Under JTAG Control
          2. 2.3.2.1.2 Set CPU to Instruction-Fetch
          3. 2.3.2.1.3 Setting the Target CPU Program Counter (PC)
          4. 2.3.2.1.4 Controlled Stop or Start of the Target CPU
          5. 2.3.2.1.5 Resetting the CPU While Under JTAG Control
          6. 2.3.2.1.6 Release Device From JTAG Control
        2. 2.3.2.2 Function Reference for 5xx and 6xx Families
          1. 2.3.2.2.1 Taking the CPU Under JTAG Control
          2. 2.3.2.2.2 Setting the Target CPU Program Counter (PC)
          3. 2.3.2.2.3 Resetting the CPU While Under JTAG Control
          4. 2.3.2.2.4 Release Device From JTAG Control
          5. 2.3.2.2.5 74
      3. 2.3.3 Accessing Non-Flash Memory Locations With JTAG
        1. 2.3.3.1 Read Access
        2. 2.3.3.2 Write Access
        3. 2.3.3.3 Quick Access of Memory Arrays
          1. 2.3.3.3.1 Flow for Quick Read (All Memory Locations)
          2. 2.3.3.3.2 Flow for Quick Write
      4. 2.3.4 Programming the Flash Memory (Using the Onboard Flash Controller)
        1. 2.3.4.1 Function Reference for 1xx, 2xx, 4xx Families
        2. 2.3.4.2 Function Reference for 5xx and 6xx Families
      5. 2.3.5 Erasing the Flash Memory (Using the Onboard Flash Controller)
        1. 2.3.5.1 Function Reference for 1xx, 2xx, 4xx Families
          1. 2.3.5.1.1 Flow to Erase a Flash Memory Segment
          2. 2.3.5.1.2 Flow to Erase the Entire Flash Address Space (Mass Erase)
        2. 2.3.5.2 Function Reference for 5xx and 6xx Families
      6. 2.3.6 Reading From Flash Memory
      7. 2.3.7 Verifying the Target Memory
      8. 2.3.8 FRAM Memory Technology
        1. 2.3.8.1 Writing and Reading FRAM
        2. 2.3.8.2 Erasing FRAM
    4. 2.4 JTAG Access Protection
      1. 2.4.1 Burning the JTAG Fuse - Function Reference for 1xx, 2xx, 4xx Families
        1. 2.4.1.1 Standard 4-Wire JTAG
          1. 2.4.1.1.1 Fuse-Programming Voltage on TDI Pin (Dedicated JTAG Pin Devices Only)
          2. 2.4.1.1.2 Fuse-Programming Voltage On TEST Pin
        2. 2.4.1.2 Fuse-Programming Voltage Using SBW
      2. 2.4.2 Programming the JTAG Lock Key - Function Reference for 5xx, 6xx, and FRxx Families
        1. 2.4.2.1 Flash Memory Devices
        2. 2.4.2.2 FRAM Memory Devices
      3. 2.4.3 Testing for a Successfully Protected Device
      4. 2.4.4 Unlocking an FRAM Device in Protected and Secured Modes
        1. 2.4.4.1 FR5xx and FR6xx Devices
        2. 2.4.4.2 FR4xx and FR2xx Devices
      5. 2.4.5 Memory Protection Unit Handling
      6. 2.4.6 Intellectual Property Encapsulation (IPE)
      7. 2.4.7 FRAM Write Protection
    5. 2.5 JTAG Function Prototypes
      1. 2.5.1 Low-Level JTAG Functions
      2. 2.5.2 High-Level JTAG Routines
    6. 2.6 JTAG Features Across Device Families
    7. 2.7 References
  4. 3JTAG Programming Hardware and Software Implementation
    1. 3.1 Implementation History
    2. 3.2 Implementation Overview
    3. 3.3 Software Operation
    4. 3.4 Software Structure
      1. 3.4.1 Programmer Firmware
      2. 3.4.2 Target Code
        1. 3.4.2.1 Target Code Download for Replicator430, Replicator430X, and Replicator430Xv2
        2. 3.4.2.2 Target Code Download for Replicator430FR (FRAM)
    5. 3.5 Hardware Setup
      1. 3.5.1 Host Controller
      2. 3.5.2 Target Connection
      3. 3.5.3 Host Controller or Programmer Power Supply
      4. 3.5.4 Third-Party Support
  5. 4Errata and Revision Information
    1. 4.1 Known Issues
    2. 4.2 Revisions and Errata From Previous Documents
  6. 5Revision History

2.3.1.2 Fuse Check and Reset of the JTAG State Machine (TAP Controller)

Reference functions: ResetTAP, ResetTAP_sbw

Each MSP430F1xx, 2xx, and 4xx flash device includes a physical fuse that is used to permanently disable memory access through JTAG communication. When this fuse is programmed (or blown), access to memory through JTAG is permanently disabled and cannot be restored. When initializing JTAG access after power up, a fuse check must be done before JTAG access is granted. Toggling of the TMS signal twice performs the check.

While the fuse is tested, a current of up to 2 mA flows into the TDI input (or into the TEST pin on devices without dedicated JTAG pins). To enable settling of the current, the low phase of the two TMS pulses should last a minimum of 5 µs.

Under certain circumstances (for example, plugging in a battery), a toggling of TMS may accidentally occur while TDI is logical low. In that case, no current flows through the security fuse, but the internal logic remembers that a fuse check was performed. Thus, the fuse is mistakenly recognized as programmed (that is, blown). To avoid the issue, newer MSP430 JTAG implementations (devices with CPUXv2 - see Table 2-15) also reset the internal fuse-check logic on performing a reset of the TAP controller. Thus, it is recommended to first perform a reset of the TAP and then check the JTAG fuse status as shown in Figure 2-14. To perform a reset of the TAP controller it is recommended that a minimum of six TCK clocks be sent to the target device while TMS is high followed by setting TMS low for at least one TCK clock. This sets the JTAG state machine (TAP controller) to a defined starting point: the Run-Test/Idle state. This procedure can also be used at any time during JTAG communication to reset the JTAG port.

GUID-A781059B-625B-49F4-8B43-5C207D017D28-low.gifFigure 2-14 Fuse Check and TAP Controller Reset

Following the same sequence in SBW mode has the side effect of changing the TAP controller state while the fuse check is performed. As described in Section 2.2.3.1, the internal signal TCK is generated automatically in every TDI_SLOT. Performing a fuse check in SBW mode, starting directly after a reset of the TAP controller, ends in its Exit2-DR state. Two more dummy TCK cycles must be generated to return to Run-Test/Idle state; one TCK with SBWTDIO being high during the TMS_SLOT followed by one TCK with SBWTDIO being low during the TMS_SLOT (reference function: ResetTAP_sbw).

Note:

A dedicated fuse check sequence (toggling TMS twice) is not required for the MSP430F5xx and F6xx families. These families implement a software mechanism rather than a hardware fuse (which needs to be checked or burned) to enable JTAG security protection.