[En-Nut-Discussion] Weird Ethernut Issue (I'm a noob, so it's probably something simple)

[Harald Kipp]

Hello Kyle,

on the ATmega128 the programming pins are shared with
the UART0 lines. The 4053 multiplexer on Ethernut 1.x
switches these pins from the RS232 to the ISP connector,
when -PROG_ENABLE is driven low. Most ISP adapters drive
this line, but STK500 doesn't. So you can short JP4 to
force the switch. It must be removed after programming
to enable RS232 again.

Some other boards use the ISP's -RESET signal. With
a little bit soldering skill you may modify your Ethernut,
tying -RESET to -PROG_ENABLE, but this may stress other
ISP adapters. With some more skills you may cut the
-PROG_ENABLE from the ISP and connect it to the ISP's
-RESET line.

After about a minute, Basemon should initiate the Ethernet
link automatically. However, in case of problems you need
the RS232 to see Basemon's output. So you need to open
JP4. One more hint: If Basemon fails to receive space
characters, it will use 38400 baud.

Harald

At 18:28 23.07.2004 -0400, you wrote:
>I have an Ethernut 1.3 rev F that had had the webport program
>installed on it. I wanted to reinstall basemon (as downloaded from
>ethernut.de) to help me learn the program. I tried and tried to get
>the computer to communicate with the ethernut through stk500.exe in
>the AVR studio package (I'm just using the basic ISP dongle). The prg
>LED was not on, only the Link and Pwr, and occasionally the act LED. I
>found some reference somewhere to jumping JP4 (the jumper right next
>to the 10-pin connector on the board), so I tried it. This lit the prg
>LED. That let me write to the ethernut. However, after writing the
>basemon hex file and reseting the board, the Link LED did not come on,
>but the Activity LED is constantly on. I tried removing the jumper on
>J4 and the programming connector, and the only change is that the prg
>light goes off then. I've tried reseting it, erasing it, re-writing to
>it, etc. What's wrong with it?