As for the TMS1400 ROM decode: page,pc,bit order is the same as on TMS1xxx, but chapters are interleaved in the columns, like so:

ch1 bit 0, ch2 bit 0, ch1 bit 1, ch2 bit 1, etc.

As you can see, the last 2 columns (of total of 32) have the fewest bits in them. This is bit 7, used on branch/call opcodes.