As far as I know, the 1400 is the player/recorder version in the series. There are 232 to 422 converters, but that still won’t do it because you need capstan over-ride for frame accurate edits. Generally the player/recorders in a company’s deck line don’t offer this. You have to get up into the edit feeder/recorders for that. The 1600 and above are edit feeder/recorders (and have 422).
However, I see on Sony’s site that the 1400A claims frame accurate editing. Whether that’s via RS-232 or not, it doesn’t say. Maybe it’s the “A” version, but I still doubt it would perform well in a studio editing situation.