DCC protocol dump from DCS50

The beast

The herb garden

First logic view

New Logic program that logs ALL data from scope output with PORTMON

THESE ARE NOT THE SAME OUTPUTS, JUST SOMETHING TO COMPARE VOLT/LOGIC

Partial view from Parallax scope app

Made a couple of basic parameters for the app named, Input Voltage Low (Vil) , Input Voltage High (Vih) , and finally Input Voltage (Vcc) variables. If the 30/70% of Vdd rule is exceeed the value is changed to a 1 or 0 giving a stepped logical view instead of scope type of view with little voltage spikes and dips.

Hex code decyphered, time to program

Here is a SS of the hex --> voltage chart. Simple pattern after the first .07. It is (5) .08 tehn a .07, all the way to the end.

I am in the processing of putting togethor a simple VB.NET with zedgraph component to read the output from PORTMON and plot it on a graph and if time permits ultimatly automaticall decipher the I2C messages.

App will be able to read the PORTMON data log file, look for the pattern of 55, data1, data2, AA and if all is valid (not more than 2 data sequences between the 55 and AA) output the data to a graph. The output captured from the scope is 50uS at 5V for both channels. Will also prob add in a logic mode that will use a couple of params at first to determine what is considered "HI" and "LOW" so it's not a voltage reference chart.

Portmon to the rescue

Well Portmon was able to capture all the messages sent/received to the oscilloscope, looks like data is sent. I setup a filter to include only IRP_MJ_READ and IRP_MJ_WRITE message types only. Here are the "good" messages that need to be deciphered or at least understood as a pattern.

******** SEND DATA REQUEST START ******
IRP_MJ_WRITE Length 1: AA
IRP_MJ_WRITE Length 1: 52
IRP_MJ_WRITE Length 1: F3
IRP_MJ_WRITE Length 1: 14
IRP_MJ_WRITE Length 1: 00
IRP_MJ_WRITE Length 1: 91
IRP_MJ_WRITE Length 1: 07
IRP_MJ_WRITE Length 1: 2D
IRP_MJ_WRITE Length 1: 05
******** SEND DATA REQUEST DONE ******

******** RECV ???ACCEPTED CMD??? ******
IRP_MJ_READ Length 1: 55

******** RECV DATA FROM SCOPE START ******
IRP_MJ_READ Length 1500: 7E 7E 7E 7E 7E 7E 7E 7E 7E .... (ch1 data)
IRP_MJ_READ Length 1500: 7E 7E 7D 7E 7E 7E 7E 7F 7E ....(ch2 data)
******** RECV DATA FROM SCOPE END ******

Above sequence loops until "STOP" button is pressed which shows up as a
IRP_MJ_WRITE Length 1: FF

Will decypher the data section tomorrow and post an excel file of results.

Osc. can't handle it

Well the oscilloscope does not do logical data logging and only captures what is on the screen and is unable to log to a file, what a limitation. I see the data flash on the screen but can not capture the entire data steam as an image or as a saved data file. Since it's USB probably has some USB --> Serial chip inside. Time to see what can be done to fix my needs w/o buying another scope.