7706 and E10A-USB from the Development Kit for SH7216

Hi!

I'm in the process of reverse engineering an old music peripheral (circa 2002 or so) that has a SH3-7706 processor in it.  My goal is to fix a few niggling bugs. 

I'm at a point where I need to be able to re-flash the device in the event I brick it (and being able to debug in situ would be a huge bonus).  I did some research and found that I needed an E10A-USB to connect to the U-HDI pads on the PCB.  I purchased a dev kit for the SH7216 which came with a E10A-USB and wired up a cable to connect the two.

I kept getting errors about targets not being supported in the Workshop program and went through the longer manual for the starter kit and found this line:

"E10A-USB for Starter Kit is a special emulator for only Renesas Starter Kit+ products."    :(

So, it seems I wasted a bit of money thinking this would be universal.

Is there any way to make this compatible with this processor, it seems these can be reflashed to support other processors?  If so, how would I go about doing this?

This is just a hobby project, not selling or manufacturing anything so I'm hoping this is still possible (and hopefully not expensive).

Any help would be greatly appreciated!  I've poured a lot of time into disassembling and reverse engineering the code and would hate to have all that go to waste.  I had assumed once I saw the U-HDI pads on the schematic that this would be something I could do.  In retrospect, I probably should have tried this first.

thanks for reading

  • Unfortunately you should really have talked to someone who knows a little about SH beforehand.
    The only E10A-USB suitable for you would be a yellow one (HS0005KCU01H).
    www.renesas.com/.../e10a-usb-hs0005kcu01h.html
    It will cost a little more than 1000€.
    Of course, the red one (HS0005KCU02H) would also work but it is more expensive.

    Digi-Key sell ab grey one (HS0005KCU11H). THIS CANNOT BE USED WITH SH7706. Problem is the same as with the one you have.

    E10A-USB are always programmed for a specific device family (H8, H8S, H8SX, SH2, SH-2A, SH3, SH3-DSP, SH4, SH-4A, ...).
    When an E10A is reprogrammed only this device support package is changed. The basic E10A-USB software cannot be changed.
    On the yellow and the red one, once it is programmed for a device family this cannot be changed by the end user. It is possible to add support for additional processor families, but this requires a special software package.
    This is also the reason why you have to be very careful when buying used E10A-USB. Once it is fixed you cannot change it. And it is most probably not programmed for SH3.
    White and grey can be reprogrammed but both support only very few device families.

    As SH3 does not have on-chip memory you may also need a debug utility that allows the emulator to write data to external flash. With SH and E10A-USB this is usually called "FMTOOL".

    The only alternative is to write the modified software to flash and check what happens, may be using some printf() to output debug status messages.
  • In reply to FrankL:

    Hi Frank,

    Thank for for the information, very helpful. And yes, I realized not long ago I should have done this first before investing so much time reverse engineering the code.

    I'm a little disappointed, but hopefully one will turn up somewhere that isn't as expensive. I had looked online and couldn't find a place to purchase one. Where would one do so if they wanted to? Do folks on the forums here sell their old devices?
  • In reply to telengard:

    Does anyone have thoughts on places to find a used E10A-USB? Given this is an older chip, I can't imagine there is much call for it anymore, but maybe there are places to find such gear?
  • In reply to telengard:

    And I just want to be absolutely sure before I put any more $$ into this endeavor:

    Will the E10A-USB allow me, with that program mentioned, to write to flash w/ the 7706?

    All I really need is the ability to write to flash in the event my code doesn't work correctly. I can debug the old fashioned way with prints, etc.
  • In reply to telengard:

    First a reply to the availability.
    if you buy a used E10A-USB you have to be sure it is programmed for SH-3 support. You will not be able to erase it if it is programmed for a different CPU family.

    As for flash programming, with the correct fmtool E10A-USB will be able to program external flash as part of the debug functionality. There is no flash programmer software that can use E10A-USB as programmer.
    I think the easier solution will be to use a standard flash programmer and connect this directly to the external flash for programming. It requires many more lines but it should be possible to by-pass SH7706 in this process.
  • In reply to FrankL:

    Thank you Frank, very helpful.

    Do you know if the 7706 supports JTAG in any way, or just U-HDI?

    And to be sure, if I purchased a new E10A-USB programmed for SH-3, with that program, I would be able to write to external NOR flash?
  • In reply to FrankL:

    Hi FrankL,

    It's been a while, but a red e10a has shown up on eBay and the back says SH3 on it

    www.ebay.com/.../293249969878

    I realize that doesn't mean it is programmed as such. If the seller runs the setup program as described in the SuperH E10a manual (page 48), if the top edit box "Device group of the emulator firmware" is empty, does that mean it has not been programmed? And I assume it needs to say SH3 if it has been programmed.

    If either is the case, I will be purchasing that item.

    thanks for any info