To add to this, the reason that the RAM was available with 9 bits in the first place is so that it could be used to make systems with ECC. It's just that you didn't have to use that 9th bit for error correction, you could use it for extra data, if you designed the system to use it that way.
To add to this, the reason that the RAM was available with 9 bits in the first place is so that it could be used to make systems with ECC. It's just that you didn't have to use that 9th bit for error correction, you could use it for extra data, if you designed the system to use it that way.