What DSUB9 to DSUB9 cable is this?
It's close to a plain old null modem cable.
DB9 female according to RS-232:

DCD (data carrier detect)
Tx  (transmit, pair with Rx)
Rx  (receive, pair with Tx)
DTR (data terminal ready, pair with DSR)
GND (signal ground)
DSR (data set ready, pair with DTR)
CTS (clear to send, pair with RTS)
RTS (ready to send, pair with CTS)
RI (ring indicator)

Everything in your pin list matches this except on a proper null modem, you are supposed to connect CTS with RTS rather than with DCD. So you appear to have some specialized, non-standard version. It's somewhat common in non-standard pinouts to give supply voltage on one pin, such as 1.

Edit: in case this was used for MCU programming over RS-232 bootloader, then it's quite likely that some of these pins are used for reset, reference voltages, mode select or similar. Older flash parts often required a high programming voltage &gt; TTL levels at some pin.