tnt 5002 interface

[theotigan]

i have write

Write(0x02,AUXMR).. also reset chip for the test

it es correct??

[Collin M]

That means that SRQ is asserted somehow. The TNT5002 cannot assert SRQ when pon is asserted or when the hardware reset is asserted.

Disconnect the GPIB cable from the TNT5002 and power it off. Then measure the resistance from the SRQ signal to ground. I think they will be shorted.

[Collin M]

Yes, writing 0x02 to AUXMR sets the pon message which holds the TNT5002 in reset. Also see my last message.

[theotigan]

i have measure 0,7Mohm it is true? or i make a mistake??

[Collin M]

That seems reasonable like a reasonable value.

Try connecting the TNT5002 back to the PCI-GPIB while keeping the TNT5002 in reset. Measure the voltage on the SRQ signal. Also do an iblines on the PCI-GPIB to see if SRQ is asserted.

[theotigan]

Hello Mr Collin

I have measure the SRQ whit the tnt5002 (connecting to PCI-GPIB) in reset and whit power on(vcc)

I measure V_srq = 0.115v and the iblines on PCI-GPIB give me SRQ = 1, I always so the same whit

 ATN;IFC,NDACS,NRFD,DAV,REN and EOI

I measure

V_ATN = 3.3v

V_IFC = 3.3v

V_NDACS = 3.3v

V_NRFD = 3.3v

V_DAV = 3.3v

V_REN = 3.3v

V_EOI = 3.3v

and the iblines on PCI-GPIB give  me

EOI  ATN  SRQ  REN  IFC  NRFD  NDAC  DAV

 0        0       1         1      0         1          1         0

And  i Read(BSR)=0x04,  I have done all the measure after Write(0x02, AUXMR), that mint after reset..

Thanks ....

[theotigan]

 

I have make another test…

I write Write(0xFF, BCR);  I read Read(BSR) = 0xFF; and iblines give me

EOI  ATN  SRQ  REN  IFC  NRFD  NDAC  DAV

 0        0       1        1     0       0          0        0

 And  I measure

V_SRQ = 0.35v

V_ATN = 3.3v

V_IFC = 3.3v

V_NDACS = 0.3v

V_NRFD = 0.3v

V_DAV = 0.3v

V_REN = 3.3v

V_EOI = 0.3v

[Collin M]

Things still are not matching up. Connecting the TNT5002 to a PCI-GPIB should not cause SRQ to assert (SRQ is active-low). My theory at this point is that some GPIB signals have been switched somehow.

Can you describe the board that uses the TNT5002? Who designed it? Have you been able to get a schematic yet? Who is the manufacturer of the PCI-GPIB?

You can try a different GPIB cable and see if that changes anything.

Another test would be to check continuity from one board to the other board when the cable is connected and both systems are powered off.

Can you also check for solder shorts at the TNT5002 and GPIB connector?

If I had a pdf copy of the schematic it would really help.

[theotigan]

I have already tested the pci_gpib board whit a (testronik) Oscilloskop and he work propertly, he reconize and i always  test some comand like  id? whit succes

i thing the board and the cable work corectly 

[Collin M]

Thanks for the schematic. What is the function of J7? Is there any cable ever connected to this?

Earlier you did an experiment where you saw SRQ was asserted by checking iblines when the TNT5002 was powered on and held in reset. Can you try the same experiment but do not apply power the TNT5002?