JUMA Amateur Radio Forum

Hi Adrian
I would like to update the firmware on my PA-100D amplifier with your latest code but have run into a problem early in the process.

I have followed your Firmware Updating guide and made up the Juma PA-100D cable as per Annex A of your document.
I am using a Prolific USB to RS232 adaptor to a Windows 10 laptop (Surface Pro 4)

With the stereo plug plugged into the PA-100D, I measure -9.9V between Pin 5 and Pin 2 of the DB9 connector on the cable. (Black multimeter lead connected to Pin 5).
This would be the TX data on idle from the PA-100D.

With the stereo plug disconnected from the PA-100D and the DB9 connected to the USB to RS232 adaptor I measure -6.33V between the tip and ground. (Black multimeter lead connected to Ground on the stereo plug). This would be the TX data on idle from the RS232 adaptor.

One question here is -6.33 volts too low for the PA-100D?

In both of the above cases I have the links in the NORMAL position.

When I use HyperTerminal to send the "I" command to the PA-100D I get no response. I have tried 115,200 baud, 9600 baud, 1200 baud and 110 baud, 8 bit, 1 stop bit no parity with no response.

Do you have any suggestions on where to look?

Kind Regards

Greg
VK4GRM

Hi, Greg
I'm sorry to hear that you are having a problem, let's see if we can determine the cause. To answer your questions, -6.3V for the TX Data line from your USB-RS232 converter is perfectly OK. I have measured the voltage from several of these converters, and both the FTDI and Prolific chipsets give about the same voltage. The MAX232 chip is quite able to accept this.

I have to first ask whether you have ever managed to communicate with your amplifier using the serial port. If not, then we need to investigate.

As you have made the connecting lead up as shown in my notes, for communication with the PA-100D with the internal jumpers set to the NORMAL mode, then you should indeed measure the TX Data idle voltage of -6V from your DB9 on the tip of the 3.5mm plug, then RX Data will be on the ring connection. You could always swap the jumpers over to the PROGRAM position, it would not damage anything, but with your data lead the connections are already correct.

Although you are getting the PA-100D Tx Data idle voltage of -9V and this verifies that at least the MAX232 level converter chip's charge pump is working, it does not mean that you are getting serial data from the microprocessor. Similarly, although you are sending data to the PA-100D, it does not mean that the microprocessor is receiving this data. If you have not already done so, I suggest you download the Juma PA-100D Control Board CPU & LCD schematics, Rev B dated 1.11.2008 from the website. If you cannot find them, then send me an email and I'll forward them to you.

If you examine the schematics, you will see the MAX232 chip on the right-hand side. The TX DATA from the PA-100D is pin 14, and the RX DATA to the PA-100D is pin 13. As you can see the TX DATA idle voltage, then there is a connection between the MAX232 chip pin 14 and your serial cable. With a multi-meter, check that there is also a connection from the ring of the 3.5mm socket to pin 13. These connections come first to the jumpers on the Frequency Sense board, and then from there to the CPU & LCD board. Check carefully all the connections to and from the Frequency Sense board.

If these are OK, then you need to verify that there is a connection between pin 11 of the MAX232 and pin 41 of the microprocessor, as well as a connection between pin 12 of the MAX232 chip and pin 42 of the microprocessor. Carefully examine the solder connections, most faults are caused by open or poorly soldered pin connections.
73, Adrian, 5B4AIY

Hi Adrian

Thanks for your detailed reply.

I will follow through with your instructions and let you know how I go.
It may be a few days as I can only look at this at night and I will need to pull the amplifier to bits to check the connections to the micro I suspect.

Will see how I go.

Thanks again

73s Greg VK4GRM

Hi Adrian

I have checked the connections and all appear to be OK.

TX and RX from tip and ring have 100ohm to the relevant connections on the MAX232 chip. This is the full path so I assume that the connections are good all the way through.

Pin 11 and 12 of the MAX232 to 41 and 42 of the PIC are zero ohms.

I will touch up with a soldering iron tomorrow or Wednesday night just to make sure.

Any other suggestions while I have the Digital board disconnected?

Have I maybe got a faulty MAX232 chip?

Thanks again for your help

73s Greg VK4GRM

Hi Adrian

Another update.

I have checked the solder connections etc and all appear to be OK.

I have checked the connections with a multi-meter and read 100 ohms between the following:

DB9 Pin 2 and Pin 14 on the MAX232
DB9 Pin 3 and Pin 13 on the MAX232

This is consistent with the 100 ohm resistors R4 and R5 on the Frequency Sense board.

With the PA-100D powered up and the Annex A cable (Juma PA-100D) connected to the PC via the USB to Serial Adapter (Prolific) I measure the following voltages on the MAX232 chip:

Pin 14 -9V Transmit Data from the MAX232
Pin 13 -6V Transmit Data from the Prolific USB to Serial adaptor
Pin 11 +5V
Pin 12 +5V

Not sure what voltage to expect on these last two as they are the TTL inputs / outputs from the microprocessor.

I tried to communicate using HyperTerminal (115200 baud, 8 data bits, 1 stop bit, no parity, no hardware flow control) and there is no response to the "I" command.
Can you confirm that this is "capital i" as in I for Information?

Are there any other commands that I can try?


I will try to replace the MAX232 chip on the weekend when I can get to a supplier and see what happens.

If you have any other suggestions please let me know.

Kind Regards

and

73s Greg VK4GRM

Hi, Greg,

This is a puzzle! Before you try and replace the MAX232 chip, it's wise to see if it is working. The old RS-232 standard inverted the data, so on the PA-100D TX Data side a +5V TTL signal is a logic '1' and this should indeed result in a -9V output signal on the TX DATA line, similarly a -6V signal on the RX DATA line should give a +5V signal to the microprocessor, so at least from a DC standpoint it looks as if your MAX232 chip is working. You could certainly see if the RX DATA line is working by simply disconnecting the DB-9 connector and taking the RX DATA pin to a positive voltage of about +3V, this should then give a logic '0' meaning 0V on the output of the MAX232 chip, pin 12. Ideally we need an oscilloscope to check that we are indeed seeing the proper data transitions on the pins of the MAX232, and if you have access to a 'scope, then you could check that the output of the MAX232 on pin 12 is a reasonable square waveform in response to RS-232 data on the RX DATA input. You could also then check to see if there are any data transitions occurring on the PA-100D TX DATA line. Failing this, perhaps by setting the PA-100D port speed to its lowest setting, 1200 Baud, and obviously setting the terminal program to 1200 Baud, you should be able to see your digital multimeter's display flickering when you look at the TX and RX DATA lines as you send data to the PA-100D.

I am somewhat surprised that you are using HyperTerminal with Windows 10. To be perfectly honest, I have never managed to get that Windows terminal program to work properly. I much prefer a simpler program such as Termite. I would suggest you try Termite and at least eliminate your terminal program as the source of the problem. I have to say that replacing chips on the board would be a last resort, and I would have to be absolutely convinced that the chip was indeed faulty.
73, Adrian

Hi, Greg,

One other suggestion. We need to be absolutely sure that there really is data going to the PA-100D. To verify this we need to loop the TX DATA to the RX DATA line of your USB-RS-232 converter. Then when you send something from your terminal program it should be immediately echo'ed back. So, get a DB-9 socket, and connect pin 2 to pin 3 and plug it in to your USB-RS232 lead, then launch your terminal program and simply type characters, you should see them being sent back to you.

73, Adrian, 5B4AIY

Hi Adrian

To answer your last post first:
I conducted the loop back test you suggested, just connected the ring and the tip together and was able to observe data being echoes back to the terminal program. I ran "the quick brown fox" to see a string of data.

I have downloaded Termite and am running it now rather than HyperTerminal. I have the free downloaded version of HyperTerminal and was using it as that is what I used years ago in a previous job. Termite seems as easy to use and simpler to change parameters on so I will stick to it from now on.

I have an oscilloscope so I soldered two small wires to pins 11 and 12 to provide easy access for the oscilloscope probe to the pins.

Pin 12 looks fine. Sending "quick brown fox" I can see plenty of square wave transitions at 1200 baud indicating that the receive path to the PIC would appear to be OK. At 115200 it is a bit harder to see but you can at least see a burst of data happening. The voltage here is 5V with downward transitions for the data so that appears to be OK.

For Pin 11 which is the output of the PIC chip I sent the "I" at 15200 and occasionally saw a transition from 5V down. I am not 100% sure on this as when I repeated it after moving the wire from pin 12 to pin 14 to see the Transmit transitions on the RS232 side of the chip I see no transition on either Pin 11 or Pin 14 so I am not sure if either the PIC or the RS232 chip has a problem. Maybe the RS232 chip is loading the output of the PIC in some fashion but I would have expected a voltage other than 5 Volts on Pin 11.

You mentioned in your first post about Setting the PA-100D port speed to its lowest setting 1200 baud.

Can you please advise how to do this?

I thought that I had read in one of the posts that the PIC would auto board to what ever data rate was sent to it. Maybe my interpretation of that post was incorrect. Alternatively if you are only sending a single character can it auto baud?
NOTE: I am using the original software supplied by JUMA in the PA-100D. I have also not found any instructions on how to do setups and calibrations on the PA-100D other than those for your software updates. If you can point me to the instructions for the original version of the software that would be appreciated?

It would be nice to monitor the transitions at 1200 as it is a bit slower and I should be able to see the transitions a bit easier on the oscilloscope.

Also I have been sending a "I" as per your instructions. Is there some other command set that is a few more characters long that should generate a longer response from the PIC to allow me to monitor the transmit side?

When I was getting what I thought was a response from the PIC it appeared to only be a single character and from your earlier instructions on loading a new software update I was expecting string of information. This potentially points to the PIC Transmit driver being the problem?

Any further thoughts or suggestions would be appreciate?

Thanks again for your help

Kind Regards

and

73s, Greg VK4GRM

Hi, Greg,

Obviously it's now time to get really serious. It has been more than 7 years since I last used the original firmware, but looking through my firmware archive the amplifier with the original firmware should respond to the following commands:

Command: I
Response: The message:

JUMA-TRX2 copyright OH7SV & OH2NLT
Software version 1.04, copyright Juha Niinikoski OH2NLT

Command: A
Response: All the A-D channels and their current data values

Command: E
Response: Dump the EEPROM contents in hexadecimal.

Command: W
Response: Write ASCII characters to the LCD. Type a character, and it should appear on the LCD, in both hexadecimal and ASCII format. Sending a CR/NL (ENTER key) will clear the display, send the ESC character will terminate the test.

Command: w
Response: Write HEX character to display: To display A for example, type 41, to clear the LCD send the CR/NL sequence, (ENTER key) again, sending the escape character in this case 1B will terminate the test.

Command: b
Response: The LCD will cycle through all possible characters from hexadecimal 00 to FF. Pressing any key will terminate the test.

If an invalid key is sent, then the message returned will be:

Key is: x, c
Try: Valid commands.

Where x is the decimal value of the key sent, and c is the ASCII character.

There is also a port loop-back test that can be invoked from the front panel at switch-on. This will take any character sent on the serial port and echo it back and display it on the LCD. To start this test from the power off state, press and hold the DISPLAY/CONFIG button, and then press the power button. Continue to hold the DISPLAY CONFIG button until the LCD displays "RS232 test" on the first line and "Waiting data..." on the second, and then release the button. Enter characters on the terminal and these should be echoed back. Obviously the serial port speed and the terminal speed must agree. The default is 9600 Baud. The amplifier will only auto-sense the port speed when loading a new firmware. I suggest you try this test first.

To change the port speed you have to enter the User Configuration menu pages. Press and hold the DISPLAY/CONFIG button, and select the desired User Configuration page by pressing the DISPLY/CONFIG button. The displayed page's data can be changed with the UP and DOWN buttons.

Briefly press the DISPLAY/CONFIG button to select a page, and when you get to the RS232 page, ensure that the TEST mode is selected. On the next page set the port speed to 9600 Baud if it is not already set. Save the current User Configuration settings by pressing and holding the PWR button, and when the long push beep sounds release the button, and the configuration will be saved.

I am also attaching a scope screen dump of the typical serial port waveform.

Let me know how you get on.
73, Adrian, 5B4AIY

Hi Adrian

I think I have it sorted. As you surmised the MAX232 chip was OK!

I am not sure but I think the default port settings may have been corrupted so it was not talking or responding to commands. Alternatively and this is perhaps more likely you need to be in the TEST mode for the port to be operational.

It took me a while to work out how to access it properly and I will document the process here for others should they need to get it working.
Following your instructions in your last post I accessed the User Configuration menu pages as follows:
Note I will list all the pages so there is a record of them all in this version of the software.

1. Power on the PA100-D


2. Press and hold the DISPLAY/CONFIG button until a long beep is heard. Release the DISPLAY/CONFIG and the following will be displayed on the LCD screen:

Auto Band Detect
Select = F-Sense

Press UP button to select the following:
Select = TRX2
Select = FT-817

Press DOWN button to return to the F-Sense.


3. Press the DISPLAY/CONFIG button and release. The following will be displayed on the LCD screen:

Serial Protocol
RS232 = JUMATRX2

Press UP button to Select
RS232 = Test

NOTE: I had to leave it in the Test mode to allow the port to be accessed for your other commands.

4. Press the DISPLAY/CONFIG button and release. The following will be displayed on the LCD screen:

Serial Speed
Baud Rate=9600

Pressing the UP and DOWN buttons allows access to the following baud rates:

115200
57600
38400
19200
9600
4800
2400
1200

I have left mine on 9600


5. Press the DISPLAY/CONFIG button and release. The following will be displayed on the LCD screen:

Displ Brightness
LCD BL = 100

Pressing the UP and DOWN buttons allows the level to be incremented or decremented by one for each UP or DOWN button press


6. Press the DISPLAY/CONFIG button and release. The following will be displayed on the LCD screen:

Display Contrast
Contrast = 2000

Pressing the UP and DOWN buttons allows the level to be incremented or decremented by fifty for each UP or DOWN button press


7. Press the DISPLAY/CONFIG button and release. The following will be displayed on the LCD screen:

SWR Protection
Limit = 3.00

Pressing the UP and DOWN buttons allows the level to be incremented or decremented by 0.1 for each UP or DOWN button press


8. Press the DISPLAY/CONFIG button and release. The following will be displayed on the LCD screen:

Temp Protection
Limit = 70 C

Pressing the UP and DOWN buttons allows the level to be incremented or decremented by 1 for each UP or DOWN button press


9. Press the DISPLAY/CONFIG button and release. The following will be displayed on the LCD screen:

Fan Control
Start = 40 C

Pressing the UP and DOWN buttons allows the level to be incremented or decremented by 1 for each UP or DOWN button press


10. Press the DISPLAY/CONFIG button and release. The following will be displayed on the LCD screen:

Auto Band Detect
Select = F-Sense

This brings us back to the beginning of the menu list.

Based on your other instructions this will be saved if the PA100-D is now powered off.

Powering up with the RS232 Serial Port connected to the PC running Termite the following screens are provided on the Termite popup:
Note Termite is configured for 9600 baud, 8 bit, 1 stop bit, no parity.


EEPROM checksums, Cal = 0, Def Cs = 0, Factory default resets = 1


JUMA-PA100 / v1.04 / 16.12.2008

Copyright Juha Niinikoski, OH2NLT


System Clock = 7372 kHz


Sending the following commands via Termite provides the responses indicated

1. Command: I


I


JUMA-TRX2 copyright OH7SV & OH2NLT


Software version v1.04, copyright Juha Niinikoski OH2NLT

Key is: 10

Try: Valid commands


2. Command: A


A


ADC 9 = 5

ADC 10 = 2269

ADC 11 = 0

ADC 12 = 0

ADC 13 = 0

ADC 14 = 400Key is: 10

Try: Valid commands


3. Command: E


E
Dump EEPROM contents


0000 0 0 0 1 1 1 1 1

0010 0 1 2 A 0 7D0 64 1

0020 3 12C 46 28 1 1 F61A FFFF

0030 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF

0040 204A 0 87 0 780 0 8 0

0050 8 0 32 1F40 B82D FFFF FFFF FFFF

0060 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF

0070 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF

0080 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF

0090 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF

00A0 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF

00B0 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF

00C0 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF

00D0 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF

00E0 FFFF FFFF FFFF FFFF FFFF FFFF FFFF FFFF

00F0 1 FFFF FFFF FFFF FFFF FFFF FFFF FFFF

Last success code = 7F Key is: 10

Try: Valid commands

I tested your other commands:
Command W: Response: Write ASCII characters to the LCD. Type a character, and it should appear on the LCD, in both hexadecimal and ASCII format. Sending a CR/NL (ENTER key) will clear the display, send the ESC character will terminate the test.

Command w: Response: Write HEX character to display: To display A for example, type 41, to clear the LCD send the CR/NL sequence, (ENTER key) again, sending the escape character in this case 1B will terminate the test.

Command b: Response: The LCD will cycle through all possible characters from hexadecimal 00 to FF. Pressing any key will terminate the test.

And they appeared to work. I could not work out how to send an ESC character in the W Command so I ended up just powering off to get out of that mode.

I also ran the Port Loop Back Test which is invoked from the power up but found this difficult to access. Sometimes I could get into this easily and other times it went into the Service and Calibration Mode. The options for the Service and Calibration Mode are detailed below:

1. Beep Length

Beep len, 0=OFF
Beep = 50 ms

Pressing the UP and DOWN buttons allows the level to be incremented or decremented by 1 for each UP or DOWN button press

2. Forward Power

Forward PWR---W
Cal mult = 8

Pressing the UP and DOWN buttons allows the level to be incremented or decremented by 1 for each UP or DOWN button press

3. RF Amplifier Current

RF Amp. I --.-A
Cal mult = 8266

Pressing the UP and DOWN buttons allows the level to be incremented or decremented by 1 for each UP or DOWN button press

4. TRX2 Polling Rate

TRX2 Poll Rate
Rate = 8000 ms

Pressing the UP and DOWN buttons allows the level to be incremented or decremented by 100 for each UP or DOWN button press

5. Set Factory Defaults

Push OPER long =
Factory defaults

6. Set Supply Voltage Calibration

Supply 11.94V
Cal mult = 135

Pressing the UP and DOWN buttons allows the level to be incremented or decremented by 1 for each UP or DOWN button press

7. Returns to Beep Length

This will do for this post.
I will follow with another on how i got on with installing your new software

73s Greg VK4GRM