I have purchased a SIXNET IO EtherTrak DS1 which converts a field DTE or DCE Serial device communications device into an Ethernet network with the serial signal mapped back to a Windows PC COM port via Ethernet. I have been working with Sixnet's best tech, Jacob C, with progress only up to the point I've described in detail below.
A Sixnet ET DS-1 is a mini industrial hardened linux box that has Ethernet on one side and a serial port on the other in the form of a RJ45 - The box comes with a DE(Male -to RJ45 adapter so one can map out the serial functions as one wishes.
SHORT CUT: The Main issue is discovered between Observation#1 - #2 and is formed as the BIG QUESTION#1 below.
LONG DESCRIPTION:
ACTION#1: I have wired my SixNet provided adapter which is a DE9M- (aka DB9M) to-RJ45 to function exactly like a DE9Male port on a PC based on FACT#1 below
FACT#1 (Verified by Weston; source:
http://www.arcelect.com/rs232.htm):
A PC Male COM port has pin 1-5 left to right on the top row and pins 6-8 left to right on the bottom row
The color functions are as follows:
Top Row
Pin 1, DCD, BLUE (SixNet adapter color)
Pin 2, RxD, GREEN (SixNet adapter color)
Pin 3, TxD, RED (SixNet adapter color)
Pin 4, DTR, WHITE (SixNet adapter color)
Pin 5, SG (Signal Ground), YELLOW (SixNet adapter color)
Bottom Row
Pin 6, DSR, BLACK (SixNet adapter color)
Pin 7, RTS, ORANGE (SixNet adapter color)
Pin 8, CTS, BROWN (SixNet adapter color)
FACT#2
A PC COM Port is considered a DTE (Data Terminal Equipment)
FACT#3
My field equipment, a Naztec Chronomax timer is a DTE (Because it requires a Null-modem cable connected to a PC COM port in order to communicate)
FACT#4
My field equipment, a Naztec TS2 Controller is a DTE (Because it requires a Null-modem cable connected to a PC COM port in order to communicate)
COMPARISON#1
A PC COM1 can communicate with a Chronomax Timer (DTE) using a Null-modem cable & a Sixnet, ether-attached to a PC can communicate serially with a Chronomax using a Null-modem cable (Results are same as expected because the sixnet factory adapter is configured based exactly how a PC port operates see FACT#1)
COMPARISON#2:
A PC COM1 can communicate with a TS2 Controller (DTE) using a Null-modem cable BUT a Sixnet, ether-attached to a PC cannot communicate with a TS2 Controller (DTE) using a Null-modem cable (Results are unexpected because the sixnet factory adapter is configured based exactly how a PC port operates see FACT#1 and the first scenario in comparison#1 yields the expected results based on FACT#1
QUESTION#1 (This is not the most important question)
What is different? Both devices, (Chronomax Timer and TS2 Controller) communicate with a PC and a Null-modem cable. However only the Chronomax Timer communicates successfully with the Sixnet configured as a PC COM port and there is FAILED COMMS with the TS2 Controller WHY? See OBSERVATION#1 & OBSERVATION#2
OBSERVATION#1: (Purpose - determine normal pin voltage on a PC com port at rest as compared to the sixnet)
By connecting a standard PC COM port (DE9Male) to a LED-Break-out-Box via a straight cable, the default LED line status is:
Pin 2, (-)
Pin 4, (+)
Pin 20, (-)
OBSERVATION#2 (Purpose - determine normal pin voltage on the Sixnet configured as a PC com port as compared to the actual PC COM port)
By connecting a Sixnet adapter (DE9Male) as mentioned above in ACTION#1 & FACT#1, to a LED-Break-out-Box via a straight cable, the default LED line status is curiously different than seen in OBSERVATION#1:
Pin 2, (-)
Pin 4, (-) (Notice the Sixnet Pin 4 is NEGATIVE as compared to the PC POSITIVE output for Pin 4)
Pin 20, (-)
SURMISED SOLUTION#1
Based on all the above and the pinpointed difference between OBSERVATION#1 & OBSERVATION#2, the solution would seem to be focused on inverting the voltage state (Polarity from Negative to Positive) on Pin 4 on the Sixnet This raises a big question see BIG QUESTION #1
BIG QUESTION #1 (My Goal is to make the SixNet emulate pin function/voltage level exactly as a PC COM port)
How does one change that state to a POSITIVE for Pin 4?
BIG QUESTION #2 ( Does not need to be answered if I get the ?#1 answered)
What nuances exist between the Chronomax and the TS2 that allow the Chronomax to communicate via the SixNet despite the fact that the pin-voltage-state is one off from an actual PC Apparently the Chronomax is tolerant and the TS2 needs precision with pin 4
