Hmm, interesting results...I've decided to go with just a single READ command and that come back with essentially 5 bytes. The problem is the first 3 are NOT consistent (at least I haven't figure them out yet, however the last two are the actual data at the location and a STOP (00). Oh, and if you do a REPEAT you get two additional different results. The first REPEAT after a new read gives you a one byte less of info, but still with the data and stop, and the second and any subsequent REPEATS ALWAYS is following three bytes "05 data 00" I assume the 05 is sent to the pod and it replies with the data and 00. Thus 05 means "read same location" Note that MAINSTAT goes Low about 50 us before PODSTAT and it rises midway through PODSTAT (about 150us I think, but this SoftLA has no grid or scale). So if you are collecting data you MUST read from a different location each time... Here is a listing of my results for a few locations and see if you can figure out the pattern Read @ Location Data Stop 0000 AA = 00 23 00 AA 00 (result) 0101 FE = 00 21 00 FE 00 0200 EF = 01 35 02 00 EF 00(result - a little longer this time...) 0300 EF = 00 26 03 EF 00 8000 EF = 02 26 80 EF 00 C000 FF = 80 26 C0 FF 00 F800 FF = C0 26 F8 FF 00 FC00 8E = F8 26 FC 8E 00 FC05 8D = FC 16 05 8D 00 FCEE EE = 05 16 CC EE 00 0200 EF = CC 35 02 EF 00 (same length as others now...) 0000 AA = 00 23 00 AA 00 Now I'll try some writes: Write @ Location Data (results) 0000 55 = 00 03 55 00 0100 AA = 55 25 01 AA 00 0200 AA = CC 23 02 AA 00 8000 44 = CC 23 80 44 00 EF08 11 = 0C 33 EF 08 11 00 (longer) Well, that's all for tonight, I'm getting tired... John :-#()#