On 09/25/2017 11:40 PM, Steve Malikoff via cctalk wrote: > Yes, you will need the controller to at least format, but not sure about just > reading/writing.
Looking at the interface, it's pretty much a "raw" interface. As in a lot of things in life, timing is everything in tapes. Tape blocks are separated by blank gaps--it's the gap that defines the block boundaries. In addition, check characters (LRCC in 7 track; CRC+LRCC in 9 track) are separated from block data by a specified number of bit times of empty space. External logic has to generate/check vertical and horizontal parity, and insert the required spacing between check characters and inter-block gaps. In addition, most formatters will correct any single-bit errors in a block (using the vertical and horizontal parity(LRCC) to locate the bit in error). Logic should also include generation/detection of tapemarks. It's not simple, but it's also not rocket science. --Chuck
