RS-232 port crashes when upgrading software for my HK AVR255

[Ivor Barnett]

Hi
I am using my P.C. (Windows 10 Pro 64 bit, Asrock H81/Core i7 etc.) to upgrade the software on my Harman Kardon AVR255 Home Theatre Amplifier. The interface is RS-232. The upgrade is in 4 parts. The first 3 parts complete successfully. When I try to start part 4, I get a window saying that communication between the computer and the amplifier has failed. Please check the RS-232 cable. The program will now close. I have tested the cable which is perfect in all respects. The situation is very frustrating, to say the least.
Can anybody shed light on this subject?

 

[Tim Locke]

Are both ends actually rs232 not one of the more modern variants?

Could it be that maybe part 3 of the update alters the rs232 settings on the amplifier?
Or of course that the part 4 alters the rs232 settings on the PC.

is the rs232 cable using all the pins? specifically CTS, RTS and DTR. Back in the day we often used just Tx,Rx and signal ground between a DCE and a DTE . ( pins 2, 3 and 7)

I know there is a specific signalling sequence and I wonder if a modern piece of equipment still bothers to use it.

 

[Comp Cmndo]

I see more than 4 parts.
http://br.harmankardon.com/tl_files...tructions - AVR 255, AVR 355 (English EU).pdf

 

[Ivor Barnett]

Are both ends actually rs232 not one of the more modern variants?

Could it be that maybe part 3 of the update alters the rs232 settings on the amplifier?
Or of course that the part 4 alters the rs232 settings on the PC.

is the rs232 cable using all the pins? specifically CTS, RTS and DTR. Back in the day we often used just Tx,Rx and signal ground between a DCE and a DTE . ( pins 2, 3 and 7)

I know there is a specific signalling sequence and I wonder if a modern piece of equipment still bothers to use it.

I think that the RS-232 cable is pin-to-pin male-female. Could this be the problem? Which pins do I need for normal RS-232 operation and is it possible that Harman Kardon use a proprietary system through the RS-232 interface?
But, it seems to me that part 4 is altering the RS-232 settings rather than the former.
Thanks for your interest and assistance
Ivor

 

[Ivor Barnett]

I see more than 4 parts.
http://br.harmankardon.com/tl_files/catalog//harman-kardon/Home/Manuals/Audio Video Receivers/AVR 255, AVR 355/Software Upgrade Instructions - AVR 255, AVR 355 (English EU).pdf

I think that there are only 4 parts. DSP x 2, MCU and Video.

 

[Ivor Barnett]

I think that there are only 4 parts. DSP x 2, MCU and Video.

Anyhow, it's when I get to part 4 that the crash occurs. I can't see what's beyond there.

 

[Norton]

I would check with Harman Kardon before attempting to make changes to the RS 232 pin out.

 

[Tim Locke]

H-K probably uses formal RS232 signalling as the amplifier is quite old. So you don't want to change anything.