Skip to main content
cosmapa
Associate III
January 19, 2008
Question

Chaining STM32 and FPGA JTAG ports

  • January 19, 2008
  • 5 replies
  • 1441 views
Posted on January 19, 2008 at 12:15

Chaining STM32 and FPGA JTAG ports

    This topic has been closed for replies.

    5 replies

    cosmapa
    cosmapaAuthor
    Associate III
    May 17, 2011
    Posted on May 17, 2011 at 12:18

    Is it OK to share the JTAG connector with both an STM32 and an FPGA?

    The circuit would be as follows:

    JTAG Connector TDI -> STM32 TDI -> STM32 TDO -> FPGA TDI -> FPGA TDO -> JTAG Connector TDO.

    Would the IAR tool be able to still work with the FPGA in the chain?

    francis
    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 12:18

    The STM32 TAPs are standard, and they support chaining.

    Don't know whether IAR supports chaining (OK with the Raisonance RLink), but I guess they do...

    Note that if you need to describe the chain for your FPGA, you will have to declare 2 TAPs in the STM32.

    slawcus
    Associate II
    May 17, 2011
    Posted on May 17, 2011 at 12:18

    What about other ST micros such as STR9? I know this is STM32 forum, but the topic was created here.

    16-32micros
    Associate III
    May 17, 2011
    Posted on May 17, 2011 at 12:18

    Dear Cosmap, Francis,

    I confirm that our STM32 is standard and could be chained to other JTAG compatible devices ( for more details refer to RM0008 reference Manual Section 2.4 and Section 2.5 ). Here (attached) I'm designing a board with both STM32 and a small CPLD from Altera and I'm using Altium designer Tool and it is working fine where I'am able to connect to both STM32 and CPLD.

    For IAR and Keil I beleive that they support this configuration in their tool in addition to Raisonance and you can ask them in their forums ( www.iar.com & www.keil.com )if they have a specific configuration file for that, if it is fixed manually and not detected upon connection.

    16-32micros
    Associate III
    May 17, 2011
    Posted on May 17, 2011 at 12:18

    It should be the same for STR9 and STR7 devices as well.