RS-232 HP 8595E Spectrum Analyzer DB-25 pinout

[candrian]

Hi all,

I own the HP 8595E which comes with 023 option (RS232). What I'm trying to, with no success yet, is to connect the HP with my PC to control it remotely.
I'm using a USB to RS232 adapter which is functional, confirmed by jumping RX/TX signals but i can't receive any replies from the SA while i can probe the commands I send on the SA DB-25 connector. The wiring on DB-25 connector is custom made. The RS232 configuration (baud rate etc) has been cross checked and is similar on both SA and RealTerm.
The commands i have tried with no results are
ID;
IP;
*IDN?

The strange thing now comes on DB-25 connector pinout. The HP 8590 Series Spectrum Analyzer Programmer's Guide https://www.keysight.com/us/en/assets/9018-01030/user-manuals/9018-01030.pdf gives the following pin out. Page 720 where the option it refers to is 043 which is different from 023 I have but both are RS232. I don't know if that makes any changes to the connector pinout but I couldn't find any relative info regarding option 023.

1. DCD Measured 0V
2. RxD  Measured -11V
3. TxD  Measured 0V
4. DTR  Measured +11V
5. GND Measured 0V
6. DSR Measured 0V
7. RTS Measured 0V
8. CTS Measured 0V
9. RI   Measured 0V

While the universal DB-25 pinout is

1. Shield Ground
2. TxD
3. RxD
4. RTS
5. CTS
6. DSR
7. GND
8. DCD
20. DTR

From the above measurements (reference the connector chassis) I may assume that the SA TxD is Pin 2 and RxD Pin 3 while the GND pin is still not clear which one is. Is it pin 5 or pin 7?
There is also a note "The spectrum analyzer checks its CTS input before transmitting data to the computer. If the CTS line is false, the spectrum analyzer will not transmit data. The spectrum analyzer transmits data when the CTS line is true"

So I tried
1. Connecting my PC USB-RS232 adapter TxD to pin 3 of SA DB-25, RxD to pin 2 and ground on pin 5. No results
2. Connecting my PC USB-RS232 adapter RxD to pin 3 of SA DB-25, TxD to pin 2 and ground on pin 5. No results
3. Connecting my PC USB-RS232 adapter TxD to pin 3 of SA DB-25, RxD to pin 2 and ground on pin 7. No results
4. Connecting my PC USB-RS232 adapter TxD to pin 3 of SA DB-25, RxD to pin 2 and ground on pin 7 and set CTS pin 8 to -6V using an external power supply in order to set it True. No results
5. I also tried connecting 8 CTS, 7 RTS and 1 DCD together but nothing changed in the communication.
6. I also tried different combinations of the above that i didn't note down.

Does anybody have the confirmed pinout of the DB-25 RS232 connector of SA 8595E?

[Emo]

Hi Candrian,

Besides the correct pinout you also need to check for baudrate and/or parity/stop bits
A safe guess for these old instruments is 9600 baud 8N1

Eric

[candrian]

I just teardown the instrument and removed the RS232 board so to confirm the pinout.

P1. GND ( It should be the shielding but it's shorted to GND)
P2. is MC1488 Output so it should be the TxD
P3. is SN75189 Input so it should be the RxD
P4. is MC1488 Output so if we follow the universal pinout it may be RTS
P5. is SN75189 Input so if we follow the universal pinout it may be CTS
P6. unconnected
P7. GND
P8. is SN75189 Input  so if we follow the universal pinout it may be DCD
P20. is MC1488 Output so if we follow the universal pinout it may be DTR

So following the Programmer's Guide I made the following connections and i gave it a try

SA             PC (USB RS232 adapter)
P1. GND     Unconnected
P2. TxD      RxD
P3. RxD      TxD
P4. RTS      DCD
P5. CTS      DTR   (measured -6V coming from the adapter)
P6. unconnected
P7. GND     GND
P8. DCD     RTS
P20. DTR   CTS

PS. SA is operating RS232 at -11V to +11V while my adapter is operating at -6V to +6V but this shouldn't be the case.

But still I don't receive any replies.

SA Baud rate is 9600, my RealTerm config is Parity None, Data bits 8, Stop bit 1, No hardware flow control

[candrian]

I'm coming back to my original post after a while.

It looks like option 23 RS232 that my Spectrum Analyzer came with isn't the correct interface to be used for remote control. The supported commands looks to be for a different use but not remote control. Maybe for a connection to a printer/plotter. After looking on the internet I found out that the 8595E with serial numbers starting with prefixes <3525U (as mine) have a single port instead of two! This is something I found completely by accident!
It sounds very strange to me, models with same part number to use different configuration boards. According to Keysight though, both kits / part numbers can be used for both editions but as I can suppose you should drill the holes on the back aluminum plate on your own for the second port to be mounted. That's why they recommend if you choose to go with the dual port when you already have a single port, to perform the installation in an Official Keysight service center. As I can imagine they will also replace the back aluminum plate with a new one.

https://docs.keysight.com/kkbopen/what-are-the-hardware-details-regarding-the-single-i-o-rs-232-gpib-parallel-interface-versus-the-dual-i-o-configurations-for-the-8590-series-588265631.html

Is there a chance any of you to have any of the following for sale?

5062-6454
or
08590-60380

[rcjoy]

When sending commands to the analyzer, are you sure you terminated each one with a semicolon?

It seems it should work with what you already have; the dual port option just adds a printer parallel port.

[candrian]

Well, if I click the copy button I can see raw data coming from the serial port. The same when I click CONFIG -> 1 of more -> 2 of more -> 3 of more -> Print config -> PRINTER SETUP , I get 0x1B 0x45.
But when I try to send IP; I don't get anything back.

[rcjoy]

The "IP;" command is not a query, so you will not get anything back from the instrument.  However you should see the instrument change it's settings back to the preset state.

Try  "ID?;" to get the instrument identification; that will return text.