Had some "fun" setting up my PC to control my TS440SAT HF rig.
One step is to install the two option chips in the rig, a CMOS 4040 and a UART chip 8251A. I had the 3030 but I had to order some 8251A's.
While waiting on the 8251A, I looked for and downloaded a few rig control programs off the 'net. One program wouldn't run, it said it needed some DLL file, and another program wanted a OCX file. Somewheres along the line I ended up installing an unwanted antivirus program, AVS, which required a special uninstall program to get rid of it (the Windows control panel uninstall wouldn't touch it). But I did find a good program, from DXLabs which did work.
While waiting for the UART chips to come, I looked around the web on what the ACC1 pinout was, and that Kenwood did something strange and inverted the CTS, RTS, TXD and RXD signals. So I figured I'd need a de-inverter circuit and built one external to the rig. To insert into the RS232 line. Considered removing the inverters in the rig, but I didn't really want to go there...
In the 6 pin ACC1 connector on my cable, I used some 5V zener diodes to clamp the RS232 voltages to not blow up the rig's 7404 TTL inverter chip. The zener clamps highs to 5V, and lows to -0.7V. I also used small 1K resistors inserted in the signal lines to avoid overloading the RS232 driver circuits in the USB to RS232 converter. This for the inputs to the rig signals, RXD (ACC1 pin 3) and CTS (ACC1 pin 4). The rig outputs, TXD (ACC1 pin 2) and RTS (ACC1 pin 5) go directly to the RS232 converter. Ground is ACC1 pin 1, and ACC1 pin 6 is NC (I connected pin 6 inside the rig to 5V to run my deinverter, turns out the control circuit board in the rig has circuit board holes to do just this, next to J56 and the 5 legged pull up resistor module RB52. I used one of those resettable fuses (they look like ceramic disk caps colored an orangeish yellow) I salvaged out of a dead PC motherboard. Turns out to be unnecessary.
Of course I had to figure out which pins on the DB9 connector are these CTS, RTS, TXD and RXD signals. To add to the fun, these signal names can vary depending on which device (PC or the rig) you are referencing to. Pick the reference that has the computer listening to signals from the rig TXD (ACC1 pin 2) and RTS (ACC1 pin 5), and the computer sending signals to the rig RXD (ACC1 pin 3) and CTS (ACC1 pin 4). Found a pdf that tells which pins of a DB25F Connector these connect to. for the 25 pin connector the pis are 2 (RXD), 3 (TXD), 4 (CTS), 5 (RTS), and 7 (GND). http://www.k6xx.com/radio/pctsinfc.pdf
is my source. Okay but my RS232 connector is the 9 pin type, so I have to find the translation.
DB9 DB25 what lammertbies called it what we call it here
1 8 Data carrier detect
2 3 Receive data TXD
3 2 Transmit data RXD
4 20 Data terminal ready
5 7 Signal ground ground
6 6 Data set ready
7 4 Request to send CTS
8 5 Clear to send RTS
9 22 Ring indicator
DB9 ACC1 what we call it
pin 2 pin 2 TXD
5 1 ground
8 5 RTS
3 3 RXD
7 4 CTS
ACC1 pin 6 connects to nothing.
And the ACC1 shell connects to the shield on the RS232 cable and DB9 connector shell.
And set the DXLab commander SW config to 4800 baud rate, 8 bit word, parity none, 2 stop bits, DTR ON, and RTS off (I used flow and it also works)
Received the UART chips today, so popped off the rig covers and installed it. I had a variety of UART chips, one was in a ceramic package, and having heard they hold up better, used it.
Hook the ACC1 to my deinverter and RS232 port (it's a USB to RS232 converter) and ran the DXLab's Commander program and no dice. I get an error message.
Start testing, decided to remove the deinverter, and that did it! Seems DXLab's Commander took care of the inverted signals in SW.