[linuxsh-dev] Frustrated with our 7750 board....

[NIIBE Y. <gn...@ch...>]

To the lin...@li..., mj...@al... wrote:
 > We seem to be having a run of bad luck with our Hitachi 7750
 > board, and we're wondering if anyone else can give us some
 > tips.

I've changed the forum to lin...@m1..., where I think the
topic is relevant.

 > First, we are able to upload S-records from Windows 
 > Hyperterminal to the board just fine, but we're unable
 > to upload even the smallest programs using Minicom or
 > "cat" or the mouse from Linux.  The symptoms are that
 > the board starts spitting a message saying 
 > "Error: InDev0Buff was full.".  Any ideas?

I believe that the error is from the ROM monitor.  As there's
no flow control feature, the buffer is overflowed.

You need ****PAUSE**** here, as there's no flow control.

 > Second, we would like to try Niibe-san's gdb stub.  But
 > we are unable to get the "fl" command to write to the
 > flash memory.
 > 
 > We type "fl", the flash image gets moved to RAM, we upload
 > the S-records for a short program, the flash gets programmed,
 > but when we do a "md 01000000" to see the flash, it's still
 > all 0xff.  Any ideas?
 > 
 > Any help would be most appreciated.

You need to specify ***OFFSET*** to the fl command here.

---------------------- Excerpt from the article I posted:

In my case, I have to set MD[2:0] ON-OFF-OFF and specify the clock
rate 6:2:1 (CPU 200MHz, Bus 66MHz, Module 33MHz), to stabilize it.

In case of Busclock=33MHz, I faced sudden stop/reset of the system, as
I've reported.  I don't know why.

Currently, it works fine for me.

To write gdb-stub image to the flash rom, I used Kermit like follows.

---------------------- Kermit
> set line /dev/ttyS0
> set speed 115200
> binary
> set transmit pause 1
----------------------  On the monitor (FLash command)
Ready> fl a0000000
---------------------- Kermit to send gdb-stub S-record
> transmit gdb-sh-stub/sh-stub.srec
----------------------

You need some "pause" as there's no protocol to control the flow.

But I don't recommend so much using GDB stub, as it's not good, no
user interface.  If you'd like hacking, please try it out.
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