| Message |
Ok, so with all the bad news going on here today, I thought I would post a good news story :-) So I'm working on the Real Time Programmability section of ZControl now that ZTalk is working (beta, should be available for download soon). Through the RTP hardware that was designed (originally designed for Honda ECU programming) to actually write a data byte to an NVSRAM chip you have to use a 74HC logic chip and fool the ECU's micro controller because the stock EPROM is only 32k or 0000h - 7FFFh hex. You have to send the data byte over pin A15 of the MC which is responsible for 8000h -10000h communications. The RTP hardware uses the logic chip to take the address byte you send and subtract 8000h from it to arrive at the actual data byte which should fall between 0000h and 7FFFh. This requires a trace to be cut on the ECU from pin A15 since we are fooling it. Well, the consult port has a built in protocol for getting ROM byte values and the native way it does this is by using the 8000h pin (A15) to do this! 0000h - 7FFFh thru the consult port is RAM addresses and 8000h-FFFFh is ROM (Is that a bizaar coincidence or what?). This means that you send the byte that you want to read (or write heheh) over 8000h PLUS the actual data byte (0000h - 7FFFh) and it spits back the appropriate value (or writes it in this case). This means that no additional ECU modification will be needed at all! Drop the NVSRAM board in place of the EPROM, and you have RTP capability thru the consult port!!!! This is HUGE! Mike
 |
 |
