ETM debug - Mictor 38-pin pinout & EMIF pins sharing

Jiri,

I am attaching the schematic of TI EVM. You can use it for reference.

2555.schematicgladiator337rev20.pdf

Please let me know if it provides the information you need.

Thanks and regards,

Zhaohong

Hi Zhaohong,

thanks for these information in detail - it will help a lot.

I just had a quick look at it - on page 2 where ETM-EMIF-MUX is depicted - honestly I would assume that SDRAM should be connected "behind" the bus switch U21. Either only ETM function (debugging) is enabled (means the switch outputs are blocked by S1=S2=L) or external interface is used (debug probe is not plugged in). OK, bus access of SDRAM can be controlled by chip select signal.

A block U20C is a bit strange for me - are inner and outer sides just defined e.g. for some design purpose? I would expect that all signals should be linked with pinout balls E9--R8 as also described in the datasheet spns162a. Most of balls D9--T8 are in a list of "no connects" (datasheet page 34).

May you clarify this?

Thanks in advance,

cheers, Jiri

Hi Zhaohong,

thanks for your feedback!

Ad (2)

OK, obviously TMS570LS30376U has been some development revision (not available in the current production roadmap) - it clarifies a lot ;-) 

Ad (1)

According to the switch datasheet a propagation time can be about 11 ns and if we consider a trace clock rate = 200 MHz... OK ;-)

I guess that we do not need a bus switch (U21 - sn74cbtlv16212) for our design - there is no intention to mount some EMIF DATA Mictor as depicted in the schematics. These pinouts shall be linked with ETM Mictor connector and parallel EMIF bus on which further devices shall be connected (e.g. SRAM) - meas similar role as played by SDRAM/TESTPIN within your Gladiator board.

You have designed two ETM Mictor connectors to cover all 32 data signals. Well, this can be useful for some special probe. However I mean that for normal ETM debugging it is sufficient to mount and connect just ETM Mictor 1 (J23 in your schematics) because most of available emulators (Segger J-Trace, Signum JTAGjet Trace,..) provide this interface. Am I right?

Thanks in advance,

cheers, Jiri

Jiri,

Do you need more information on this topic? Would you please select the "verified" button if you consider that this question is answered?

Thanks and regards,

Zhaohong

Hello Zhaohong,

yes, I am very satisfied with your hints and advises - however I have one further question (the last one on this topic, I hope ;-)):

My intention is to mount only Mictor-38 connector on the board for being the trace feature available. On the other side, I also want to have a possibility to connect with simpler emulator without trace feature and Mictor interface. So I will need an adapter between on-board Mictor-38 connector and JTAG 20 pin connector supplied with the emulator.

(1) May you recommed me some commercial adapters - I have found e.g. ADP-ETM-JTAG20 and ADP-JTAG20-ETM (I think the second one is determined for my purpose) by hitechglobal.com

(2) I guess that is easy to interface ETM Mictor-38 connector with SWD JATAG 20-pin connector and produce a simple home adapter ;-) My question is - can I directly link the ETM pins with JTAG pins - e.g. no additional resistors needed?

In best case I would like to finalize that with similar route table as described here - http://e2e.ti.com/support/microcontrollers/hercules/f/312/t/208528.aspx

many thanks in advance,

cheers Jiri

Hello Zhaohong,

thanks for your hints! 

Information you provided me are very useful and sufficient definitely. Maybe I will re-open the discussion when encountering another issue ;-)

Best regards

Jiri