I programmed 9s52. Thats not a problem. But I had a doubt that it is the need for TxD and RxD. Reply Delete reply Mikromatik Mladen September 24 2012 at 11:34 AM can I use this programmer to program AT9S253 with 12MHz Crystal Response Delete Response reply Sprem October 7th 2012 at 1:50 PM Hai Gaurav. Very NIC e posts.: I have a USB programmer for the 9S series from Electronics for you. This is the link. They say they should make students not able to work in industries and ruin their professional life. I use the 9s series MCU is pretty much because they are cheap and easy to program no fuses or other problems. The cars ISP programmer supports in-system programming via the PC RS232 serial port. I programmed 9s52. Thats No problem. But I had a doubt that what is the need of TxD and RxD.Reply Delete Replies Reply Mikromatik Mladen September 24 2012 at 11:34 AM Can I use this programmer to program AT9S253 with 12MHz crystal Reply Delete Replies Reply sprem October 7 2012 at 1:50 PM hai gaurav.very nice post.: i have a USB programmer for 9S series from electronics for you.this is the link.They say that theyll make students not capable to work in the industries and ruin their professional life.I use the 9S series mcus quite a bit because they are inexpensive and easy to program no fuses or other problems .The on-board ISP Programmer supports in-system programming via PC RS232 serial port.