MythTV -- IR Blaster -- lirc -- Samsung SIR-S300W

Anyone got a good recipe for getting their MythTV box talking to a samsung SIR S300W DirectTV Set-top box?

I've dug-up the following links which are all promising. It's looking like I'm going to need a trip to Fry's to make an ir Blaster.

Does LiRC work by bitbashing over the serial port? Is it wiggling the RTS/CTS/DTR lines? Anyone ... anyone ... Bueller ... anyone?

http://www.irblaster.info/#RS232_IR

http://losdos.dyndns.org:8080/public/mythtv-info/MythTV_DISH_IR_LED_TX_via_Modified_LIRC.html

http://www.lirc.org/transmitters.html


(lirc config file: SIR-S300W)