A few more hundred lines of code have been written. I still have not absolutely verified the lower level communications protocols to my satisfaction, but I hope to get that done before the end of September. I am satisfied with the hardware design though, and have submitted the gerber files to my manufacturer for cost estimates. I should know more in a few weeks.

Real progress today...The second round of boards was received in the mail. I quickly ran down to the basement and mounted all of the tiny SMD components. The first impressions are excellent. The USB device appears in Windows correctly. All of the initial testing is going well. The next level of testing, will be to make sure that the physical protocol layers on the devices different channels are all working properly with the Rovers. This is a major milestone in the project!!!

 I am on a 2 week vacation coming up, so you will not hear back from me for awhile.

Update: I have completed the testing of all of the lower level physical layer protocols. Everything is perfect and working properly. The EAS line protocol is working great and I can get responses from the EAS ECU. The ISO9141-2 line protocol is functions perfectly and I can also get a response back into the software. The last minute addition of the seperate slow initialization K and L line hardware also works as designed. All of the LED signaling works as designed as well. Although I am a bit concerned about the power consumption of the LEDs. I need to investigate that further. The USB bridge chip gets a bit warm, I think I chose the wrong LEDs. They may be a bit inefficient. Overall, this is wonderful news. I only have a few minor changes to the board and then the hardware is done.

The first round of boards have bee received. Good News, the boards fit the enclosures. When the second round of boards is received next week, I will actually complete the first prototype board.

The corrected boards have now been ordered. I was able to add the L Line using the RTS line of the Serial Data Bus Interface. I also was able to add a duplicate K Line using the DTR Line. I added the duplicate K Line because it will be impossible to get the normal Tx Serial UART to go down to the 5 baud wake up necessary for initialization of the ISO protocol. So the second K line will be used to pragmatically perform the 5 baud wake up sequence and then go quiet when the normal 10400 communications commence with the standard Tx UART.

Although..., if memory serves me, it is possible to emulate the slow 5 baud wake up using a higher more obtainable UART speed, like 9600 or 10400, using a manual bit-bang method. But I am not sure if I have access to this type of control with the UART chip that I am using. I will have to go digging through my notes. But now at least I have a secondary K Line in case I can not get the slow init to operate as designed through the normal Tx line. More flexibility through redundancy is usually never a bad thing.

I am diving deeply into the programming of the insane ammounts of fault codes that this project requires sifting through. The different model years across the models does not help either. As always, this will take longer than usual. 

I also realized that in my rush to get the circuit boards out to the manufacturer, I completely forgot to add the L Line in the ISO 9141-2. The L Line is a throw back to the very early ISO 9141-2 protocol implementations. This usually would not be a problem with newer cars. But the P38a Range Rover needs the L line on several vehicle computers. This embarasing omission will of course have to be fixed. It will not slow down the development, it will simply cost me more money for the second board revision.

Gives me time to get the programming well underway.

It is official, the circuit boards have been ordered. This step will allow me to construct the first handfull of working tools. Assuming that the boards work and everything was constructed correctly, then I can submit these designs to the manufacturer for full production and assembly. The boards take 10 business days to manufacturer and about 3 days for shipping. So I will not be getting the boards for awhile.