MPC57XX JTAG programming

[vincentbbbb]

Hi, Where can I get more information about flash programming via JTAG for MPC57XX.  I know my device has a 6-bit instruction register, but the only doc I could find was AN4365 which is for 5-bit instruction register.  Are there details somewhere?

Thanks

[davidtosenovjan]

It is the same in principle, but register has more bits. There is not further appnote, but instructions should be described in the RM as example below:

[vincentbbbb]

Is it possible to get more details.  Here is what I am doing to read memory from my chip:

1- Select e200Z4a TAP core by sending 0x28 with 6-bit instruction register

2- Sending 0x7C with 10-bit instruction register to select Nexus-3 Access in the OCMD register

3- Follow sequence to set RWA and RWCS to read memory (Section 64.16.3 in manual).

However, I always get 0's when reading memory using this method.  I also get all 0's when reding JTAG_ID from OCMD register (0x2).

Is there an additional step?

Regards

[davidtosenovjan]

Actually what is your MCU?

It should be the same (only with longer instructions) and AN4365 could be possible to use as well.

Here you may see example scripts, although again only prepared for MPC55xx/56xx devices:

https://community.nxp.com/t5/MPC5xxx-Knowledge-Base/Example-JTAG-access-Addendum-to-application-note...

[vincentbbbb]

Hello,

My chip is MPC5748G.  I am trying to download the example from the link provided, but the  

JTAG.cmm.zip file is not accessible.  Do you have an example for my chip?

[davidtosenovjan]

I can download the file without issues even I am not logged in.

[mintsee]

Spoiler

Hi,

So related to this, ive followed the commands in the example, however i still cant access the read function in nexus3. Ive used a logic analyser on my devboard to see what a third party tool does, and can access it fine, however when replicating the sequence of commands i cant read at all. Trying to learn more about JTAG and chose the SPC5748G Dev-Kit for this.


I can see this difference in response between my attempt with a DIY tap-controller using FTDI, and the 3rd party tool. Then everything after this is different, and any attempt at reading data i get 0's


Any ideas? It would be good if the examples were more fleshed out, or we could understand the MCU responses however i cant find anything on the expected MCU responses

[mintsee]

accidentally marked this as spoiler, please expand it