Sorry I just saw you also asked about the unexpected start and end addresses.
Why would you expect the initial address to be 641? In DAF files (including PCK), we have the following structure of records (each record is 1024 bytes):
- We always start with a single File Record
- Then, a variable number of optional comment records (there might be none present)
- Then one summaries record
- This is immediately followed by one names record
- Then a number of data records, variable, as many as required to store all the segments whose summaries were given in the previous summaries-names records pair
- The set of (1 summary record - 1 names record - X data records) is repeated until we cover all the included segments
So this means in the minimum case of a file with no comment records, we would have 3 full records (file record + 1 summary record + 1 name record) before the beginning of the first data record. This would mean the earliest address available for array data would be the 3073th byte (note that SPICE describes addresses as double precision words, but I’m handling them as byte addresses currently).
Why did you expect the start address to be 641?
Thanks!