More UCB testing...

Hi all,

I've been running comms tests on my powercomms board (v1.2) and ucb (v1.2.0 - the one without silkscreen) - the poke utility and minicom echo
Powercomms on its own: data echoes back to screen & poke echo returns with
<54><51><31><02><00><00>[54][51][31][02][00][00][d0]Read fail 2
<54><51><31><02><00><00>[54][51][31][02][00][00][d0]Read fail 2
<54><51><31><02><00><00>[54][51][31][02][00][00][d0]Read fail 2
<54><51><31><02><00><00>[54][51][31][02][00][00][d0]Read fail 2

as expected.

With a UCB connected, no PIC, and jump pin 7 & 8, i got the same results.
With PIC inserted (stepmotor.hex from sourceforge) i got <54><51><31><02><00><00>[54][52][30][00][02][bd][ACK Received]

I then ran the RepRap host software stepper tester:
The X axis slider is in high contrast, the Y and Z are greyed out. I moved the slider up. It moved for a few seconds and LED flashed. The stepper tester GUI closes. The following errors are displayed:
'Native lib Version = RXTX-2.1-7
Java lib Version = RXTX-2.1-7
Receive error, re-sending: Timeout receiving byte
0->8: 0
Receive error, re-sending: Timeout receiving byte
0->8: 0
Device at address 8 not present
Receive error, re-sending: Timeout receiving byte
0->2: 3 3e 2
Device at address 3 not present
Device at address 4 not present
CRC error
Receive error, re-sending: CRC error
0->2: 5 ec dd 5
Receive error, re-sending: Timeout receiving byte
0->2: 5 ec dd 5
Receive error, re-sending: Timeout receiving byte
0->2: 4
Device at address 2 not present
Ignored IO exception in position update: java.io.IOException: Device at address 2 not present'

Then (just for fun!) i ran the poke utility again. This time it gives me the proper message!
<54><51><31><02><00><00>[54][51][31][02][00][00][d0]Read fail 2 (X4)

so i ran dance.sh and got <54><51><33><02><00><03><00><00>[54][51][33][02][00][03][00][00][d2]Read fail 2
<54><51><33><02><00><03><00><00>[54][51][33][02][00][03][00]
it stops there.

Is this all still just a Rx/Tx mix-up?

> With PIC inserted (stepmotor.hex from sourceforge) i got
> <54><51><31><02><00><00>[54][52][30][00][02][bd][ACK Received]

And if you repeat that, does it work repeatedly? Like 10 times in a row? The "[ACK Received]" is a very good sign, serial wiring is fine if you see that.

> Is this all still just a Rx/Tx mix-up?

Maybe not. If you can run poke once as above, and then after that it fails (until you power cycle the UC, then you most likely forgot to jumper the sync connector, P3. The PIC is then in a loop waiting for a SYNC pulse and ignores all incoming serial packets until its gets that sync pulse. There is now a note about this in the Wiki page.

You actually appear to have correct serial wiring -- you should congratulate yourself and be very happy about this :-)

Jonathan

Excellent!!><

Although, there was a jumper on P3.
When i ran dance.sh again i got ...[ACK Received] repeatedly. I ran the host software again, x axis moved up and down a few times and the slider went grey and got the same errors as above. I tried poke again and it gave me the <54><51><31><02><00><00>[54][51][31][02][00][00][d0]Read fail 2 message. When i power the board down and up and try poke again i get the [ACK Received] again.

I'm guessing somewhat, but my hunch would be that either the serial wiring is going intermittent, or the sync wiring is. I'd suggest checking solder joints from PIC to the SYNC jumper, and the sync jumper itself, carefully. Maybe when it next fails, wiggle the sync jumper and see whether things come back to life?

As a further test, maybe get things working and then deliberately remove the sync jumper and see whether the symptoms are the same as you are seeing when you don't deliberately remove it?

Jonathan

Hi,

We couldn't find this note about jumpering P3/SYNC on the wiki, is it still there?

We also ran into the problem that the communications tests in [www.reprap.org] seem to only intermittently work until you have installed the resistors (R10, R11) mentioned in [www.reprap.org].

Before installing the resistors, we discovered that the serial communication only works reliably when someone touches the sync pins, providing some resistance

pix.

The jumpering worked for me, but was removed as not needed ... by someone
for whom it was not needed :-)

Whether those resistors are needed before the test works seems to vary from
board to board, a couple of people have noted things work better with them
installed. Without them the SYNC pin at the PIC is (I think) floating, and
apparently it floats one way on some boards and the other way on others!

We should probably document this on the wiki. If someone with more
electronics background than I have can confirm the need for R10 and R11
for me, I'll go ahead and make the change to the instructions. It would
also be good to verify that adding them doesn't "hurt" if the board later
becomes an Extruder Controller rather than a Stepper Controller.

Jonathan

---

---

Jonathan