DIYDan

I have a JZ20-J-R31-Z and a PC with a DB9 Female serial port. I fancy the making a serial programming cable for it, because I can. I see the Jazz Jack inside the case is just a standard 10 pin IDC motherboard header, see image below. https://ibb.co/74tfYJ3 I have an drawing of the pins 1 to 9 on the DB9 and pins 1 to 10 on the Jazz jack 10 pin IDC header, see below. https://ibb.co/fGthgVH After a bit of internet research I believe pins 2 (RxD < TxD), 3 (TxD > RxD), 4 (DTR > Power), 5 (Signal Ground) & 7 (RTS > Power) are used on the DB9 but not sure where these connect to on the Jazz IDC header, I see the DB9 to RJ11 is 2-3, 3-4, 4-6, 5-2+5, 7-1. Does anyone have any ideas on the IDC side?