|
Finished building the LPF Control board, no detectable shorts or
opens and no smoke escaped. The board is configured for I2C
addressing and the address jumpers are set for address "25"(Open,
Short, Open). However address LPF not found at 25, running SDT
Ver66-9. I ran I2C Scan and an address of "28" is showing up on
wire 2. How is that possible?
--
73
Bob W3RDL
|
Soldering JP2 while leaving JP1 and JP3 open makes the address bits 101 (they are high by default and soldering the junction pulls them to ground). This should correspond to the address 0x25, as you say.
The AD7991 chip that is also on the LPF control board has an address of 0x28 or 0x29, so I think that's what you're detecting with the I2C scan. This confirms that the cable isn't broken -- something must be wrong regarding the MCP23017 chip on your board. Look for solder bridges, missing parts, misalignments, etc.
On Wednesday, April 23rd, 2025 at 2:41 PM, Robert Luken W3RDL via groups.io <now.w3rdl@...> wrote:
Finished building the LPF Control board, no detectable shorts or
opens and no smoke escaped. The board is configured for I2C
addressing and the address jumpers are set for address "25"(Open,
Short, Open). However address LPF not found at 25, running SDT
Ver66-9. I ran I2C Scan and an address of "28" is showing up on
wire 2. How is that possible?
--
73
Bob W3RDL
|
The LPF control cable connects to the “BANDS” connector on the MAIN board, J12…. and to the “BANDS” connector on the LPF Control board J21.? ?It should be on on WIRE2 at hex address x25 which is “101”… or JP1 and JP3 open, and JP2 closed.? Address x28 on WIRE2 is the AD7991 A/D for the power/ swr.? Have a look here: ? ? So if you are not getting a response at x25, then something is up with U15… the MCP23017 multiplexer… ? ? Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ?
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From: [email protected] <[email protected]> On Behalf Of Robert Luken W3RDL via groups.io
Sent: Wednesday, April 23, 2025 1:41 PM
To: [email protected]
Subject: [SoftwareControlledHamRadio] LPF Control Board addressing help? Finished building the LPF Control board, no detectable shorts or opens and no smoke escaped. The board is configured for I2C addressing and the address jumpers are set for address "25"(Open, Short, Open). However address LPF not found at 25, running SDT Ver66-9. I ran I2C Scan and an address of "28" is showing up on wire 2. How is that possible? --
73  Bob W3RDL
|
OOPS… was reading linearly and missed this response. ? ? Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ ? Owner - Operator Big Signal Ranch – K9ZC Staunton, Illinois ? Owner – Operator Villa Grand Piton – J68HZ Soufriere, St. Lucia W.I. Rent it: ? Moderator: North American QRO Group at Groups.IO. Moderator: Amateur Radio Builders Group at Groups.IO. ? email:? bill@... ? ?
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Show quoted text
From: [email protected] <[email protected]> On Behalf Of Oliver KI3P via groups.io
Sent: Wednesday, April 23, 2025 3:42 PM
To: [email protected]
Subject: Re: [SoftwareControlledHamRadio] LPF Control Board addressing help? Soldering JP2 while leaving JP1 and JP3 open makes the address bits 101 (they are high by default and soldering the junction pulls them to ground). This should correspond to the address 0x25, as you say. The AD7991 chip that is also on the LPF control board has an address of 0x28 or 0x29, so I think that's what you're detecting with the I2C scan. This confirms that the cable isn't broken -- something must be wrong regarding the MCP23017 chip on your board. Look for solder bridges, missing parts, misalignments, etc. On Wednesday, April 23rd, 2025 at 2:41 PM, Robert Luken W3RDL via groups.io <now.w3rdl@...> wrote:
Finished building the LPF Control board, no detectable shorts or opens and no smoke escaped. The board is configured for I2C addressing and the address jumpers are set for address "25"(Open, Short, Open). However address LPF not found at 25, running SDT Ver66-9. I ran I2C Scan and an address of "28" is showing up on wire 2. How is that possible? -- 73  Bob W3RDL
?
|
Oliver, thanks for the reply. I thought I had traced out all of
the pins on the 23017, but I may have missed something. I'll check
things again. About the AD7991, "BIT" has been showing an Ad7991
at x29 without the LPF board installed. I've always wondered about
that.
On 4/23/2025 4:41 PM, Oliver KI3P via
groups.io wrote:
Soldering
JP2 while leaving JP1 and JP3 open makes the address bits 101
(they are high by default and soldering the junction pulls them
to ground). This should correspond to the address 0x25, as you
say.
The
AD7991 chip that is also on the LPF control board has an address
of 0x28 or 0x29, so I think that's what you're detecting with
the I2C scan. This confirms that the cable isn't broken --
something must be wrong regarding the MCP23017 chip on your
board. Look for solder bridges, missing parts, misalignments,
etc.
On Wednesday, April 23rd, 2025 at
2:41 PM, Robert Luken W3RDL via groups.io
<now.w3rdl@...> wrote:
Finished building the LPF Control board, no detectable
shorts or opens and no smoke escaped. The board is
configured for I2C addressing and the address jumpers are
set for address "25"(Open, Short, Open). However address LPF
not found at 25, running SDT Ver66-9. I ran I2C Scan and an
address of "28" is showing up on wire 2. How is that
possible?
--
73 
Bob W3RDL
--
73
Bob W3RDL
|
No joy. I checked continuity from U15 to the band header pins,
OK. I checked all IC pins for solder bridges and opens and all
resistors and capacitors. Powered the board externally and checked
all voltages on ICs. A0, A1, and A2 on U15 show 5v, 0v, and 5v.
Checked the cable(pin for pin) used for the BPF board. When
connected to the LPF board, BIT reports "23017 not found at x25".
Since I2SCAN showed a device at x28, I recompiled with LPF at x28,
BIT reports "LPF 23017 not found at x28".?
Made a daisy chain cable for Main to BPF to LPF band. BIT reports
"BPF 23017 not found at x24 and LPF 23017 not found at x25".?
The I2C lines show continuity between the Band connector header
pins and U15. Could U15 be bad?I'll reheat all of the pins again
before I swap it out, assuming I have a spare.
On 4/23/2025 5:30 PM, Robert Luken
W3RDL via groups.io wrote:
Oliver, thanks for the reply. I thought I had traced out all of
the pins on the 23017, but I may have missed something. I'll
check things again. About the AD7991, "BIT" has been showing an
Ad7991 at x29 without the LPF board installed. I've always
wondered about that.
On 4/23/2025 4:41 PM, Oliver KI3P via
groups.io wrote:
Soldering
JP2 while leaving JP1 and JP3 open makes the address bits 101
(they are high by default and soldering the junction pulls
them to ground). This should correspond to the address 0x25,
as you say.
The
AD7991 chip that is also on the LPF control board has an
address of 0x28 or 0x29, so I think that's what you're
detecting with the I2C scan. This confirms that the cable
isn't broken -- something must be wrong regarding the MCP23017
chip on your board. Look for solder bridges, missing parts,
misalignments, etc.
On Wednesday, April 23rd, 2025 at
2:41 PM, Robert Luken W3RDL via groups.io <now.w3rdl@...>
wrote:
Finished building the LPF Control board, no detectable
shorts or opens and no smoke escaped. The board is
configured for I2C addressing and the address jumpers are
set for address "25"(Open, Short, Open). However address
LPF not found at 25, running SDT Ver66-9. I ran I2C Scan
and an address of "28" is showing up on wire 2. How is
that possible?
--
73 
Bob W3RDL
--
73
Bob W3RDL
--
73
Bob W3RDL
|
The daisy chain test sounds like it might be a clue. Does your radio find the BPF if that board is connected to the main board? It uses the same I2C bus, so this will confirm that the problem is not on the main board side. If adding the LPF board to the daisy then prevents the main board from discovering both the BPF and the LPF boards, then this implies that something on the LPF board is messing with the I2C lines, likely by pulling them high or low.
If the test above indicates that the I2C lines are being messed with on the LPF board then check the other parts of the board where the I2C lines run for shorts. - Are the pullup resistors R14 and R12 present and not shorted?
- Are there any shorts around pins 1 and 2 of U20?
On Thursday, April 24th, 2025 at 12:51 PM, Robert Luken W3RDL via groups.io <now.w3rdl@...> wrote:
No joy. I checked continuity from U15 to the band header pins,
OK. I checked all IC pins for solder bridges and opens and all
resistors and capacitors. Powered the board externally and checked
all voltages on ICs. A0, A1, and A2 on U15 show 5v, 0v, and 5v.
Checked the cable(pin for pin) used for the BPF board. When
connected to the LPF board, BIT reports "23017 not found at x25".
Since I2SCAN showed a device at x28, I recompiled with LPF at x28,
BIT reports "LPF 23017 not found at x28".
Made a daisy chain cable for Main to BPF to LPF band. BIT reports
"BPF 23017 not found at x24 and LPF 23017 not found at x25".
The I2C lines show continuity between the Band connector header
pins and U15. Could U15 be bad?I'll reheat all of the pins again
before I swap it out, assuming I have a spare.
On 4/23/2025 5:30 PM, Robert Luken
W3RDL via groups.io wrote:
Oliver, thanks for the reply. I thought I had traced out all of
the pins on the 23017, but I may have missed something. I'll
check things again. About the AD7991, "BIT" has been showing an
Ad7991 at x29 without the LPF board installed. I've always
wondered about that.
On 4/23/2025 4:41 PM, Oliver KI3P via
groups.io wrote:
Soldering
JP2 while leaving JP1 and JP3 open makes the address bits 101
(they are high by default and soldering the junction pulls
them to ground). This should correspond to the address 0x25,
as you say.
The
AD7991 chip that is also on the LPF control board has an
address of 0x28 or 0x29, so I think that's what you're
detecting with the I2C scan. This confirms that the cable
isn't broken -- something must be wrong regarding the MCP23017
chip on your board. Look for solder bridges, missing parts,
misalignments, etc.
On Wednesday, April 23rd, 2025 at
2:41 PM, Robert Luken W3RDL via groups.io <now.w3rdl@...>
wrote:
Finished building the LPF Control board, no detectable
shorts or opens and no smoke escaped. The board is
configured for I2C addressing and the address jumpers are
set for address "25"(Open, Short, Open). However address
LPF not found at 25, running SDT Ver66-9. I ran I2C Scan
and an address of "28" is showing up on wire 2. How is
that possible?
--
73 
Bob W3RDL
--
73
Bob W3RDL
--
73
Bob W3RDL
|
Oliver, success, I went back and re-flowed all of the connections
on U15 on the LPF control board and checked continuity on all the
pins again. Everything was ok. Then I remembered that there was a
7991 at U20 which was also connected to the I2C lines. I checked
the pins and found a short and an open and I couldn't tell if the
IC was on correctly. It's so small and the markings are impossible
to read. So I removed it, cleaned up the pads and the IC leads.
Was able to verify an alignment dot and replaced it. Continuity
checks went ok, and now it's working. It was probably on
backwards. Thanks for the help. Now I can get back to winding
Toroids.
On 4/24/2025 7:55 PM, Oliver KI3P via
groups.io wrote:
The
daisy chain test sounds like it might be a clue. Does your radio
find the BPF if that board is connected to the main board? It
uses the same I2C bus, so this will confirm that the problem is
not on the main board side. If adding the LPF board to the daisy
then prevents the main board from discovering both the BPF and
the LPF boards, then this implies that something on the LPF
board is messing with the I2C lines, likely by pulling them high
or low.
If
the test above indicates that the I2C lines are being messed
with on the LPF board then check the other parts of the board
where the I2C lines run for shorts.
- Are the pullup resistors
R14 and R12 present and not shorted?
- Are there any shorts around
pins 1 and 2 of U20?
On Thursday, April 24th, 2025 at
12:51 PM, Robert Luken W3RDL via groups.io
<now.w3rdl@...> wrote:
No joy. I checked continuity from U15 to the band header
pins, OK. I checked all IC pins for solder bridges and opens
and all resistors and capacitors. Powered the board
externally and checked all voltages on ICs. A0, A1, and A2
on U15 show 5v, 0v, and 5v. Checked the cable(pin for pin)
used for the BPF board. When connected to the LPF board, BIT
reports "23017 not found at x25". Since I2SCAN showed a
device at x28, I recompiled with LPF at x28, BIT reports
"LPF 23017 not found at x28".
Made a daisy chain cable for Main to BPF to LPF band. BIT
reports "BPF 23017 not found at x24 and LPF 23017 not found
at x25".
The I2C lines show continuity between the Band connector
header pins and U15. Could U15 be bad?I'll reheat all of the
pins again before I swap it out, assuming I have a spare.
On 4/23/2025 5:30 PM, Robert
Luken W3RDL via groups.io wrote:
Oliver, thanks for the reply. I thought I had traced out
all of the pins on the 23017, but I may have missed
something. I'll check things again. About the AD7991,
"BIT" has been showing an Ad7991 at x29 without the LPF
board installed. I've always wondered about that.
On 4/23/2025 4:41 PM, Oliver
KI3P via groups.io wrote:
Soldering
JP2 while leaving JP1 and JP3 open makes the address
bits 101 (they are high by default and soldering the
junction pulls them to ground). This should correspond
to the address 0x25, as you say.
The
AD7991 chip that is also on the LPF control board has an
address of 0x28 or 0x29, so I think that's what you're
detecting with the I2C scan. This confirms that the
cable isn't broken -- something must be wrong regarding
the MCP23017 chip on your board. Look for solder
bridges, missing parts, misalignments, etc.
On Wednesday, April 23rd,
2025 at 2:41 PM, Robert Luken W3RDL via groups.io <now.w3rdl@...>
wrote:
Finished building the LPF Control board, no
detectable shorts or opens and no smoke escaped. The
board is configured for I2C addressing and the
address jumpers are set for address "25"(Open,
Short, Open). However address LPF not found at 25,
running SDT Ver66-9. I ran I2C Scan and an address
of "28" is showing up on wire 2. How is that
possible?
--
73 
Bob W3RDL
--
73
Bob W3RDL
--
73
Bob W3RDL
--
73
Bob W3RDL
|
K9HZ