Re: [ECOS] Can't connect to remote Evaluator 7T

Mark Salter
2003-02-19T19:22:58Z

>>>>> Jonathan Larmour writes:

> Gary D. Thomas wrote:
>> On Wed, 2003-02-19 at 10:41, Mark Salter wrote:
>>
>>>>>>>> Quality Quorum writes:
>>>
>>>> On Wed, 19 Feb 2003, Mark Salter wrote:
>>>
>>>>> Not only that, from my experiments with a cable tap, nothing is going out
>>>>> of the PC to the target. The write(2) succeeds, but nothing is sent on
>>>>> the wire. Closing and reopening the serial device usually clears up the
>>>>> problem.
>>>
>>>> Connect through minicom and make sure that target responds with gdb packet
>>>> when you send enter. My $0.02.
>>>
>>> The target is sitting at the RedBoot prompt. I physically tapped the
>>> serial line and watched from another host. The packet from GDB never
>>> makes it to the wire. If I startup minicom on the host with GDB still
>>> trying to connect, then data starts flowing on the wire again although
>>> GDB and minicom are fighting over the read data.
>>>
>>
>>
>> Maybe it's a handshake issue? Perhaps GDB is leaving or setting
>> the port into a handshake mode (that may not work) and minicom does
>> not. Or some such combination. Checking with "stty </dev/XXX"
>> from another window while both applications are running might
>> give some useful insights.

> As I said earlier :-). I think making sure it's off using minicom would be
> more reliable (from user error) though.

% stty -a </dev/ttyS0
speed 115200 baud; rows 0; columns 0; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>;
eol2 = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W;
lnext = ^V; flush = ^O; min = 1; time = 5;
-parenb -parodd cs8 hupcl -cstopb cread clocal -crtscts
ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr -icrnl -ixon -ixoff
-iuclc -ixany -imaxbel
-opost -olcuc -ocrnl -onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0
ff0
-isig -icanon -iexten -echo -echoe -echok -echonl -noflsh -xcase -tostop
-echoprt -echoctl -echoke

Starting minicom does not reliably get it going again. If I wait for GDB
to timeout and retry a target command, it usually works. The act of closing/
opening the tty device seems to get it unclogged.

--Mark