Wired remote for Alpine

[fratello]

Hello !
Since I have good results with "wired remote for Pioneer HU" (see : http://www.picbasic.co.uk/forum/showthread.php?t=15229 ) one friend ask me to build something similar for his Alpine ...
I found a good topic here : http://www.mp3car.com/input-devices/...ol-pinout.html , where it's described the "protocol".
I intend to use the same hardware : PIC 16F628A and remote control stalk near the steering wheel, from Renault.
But...I need help to put in PBP this :

Vol Up    110101111101101110101011110110111101011011010101
Vol Dn    110101111101101110101011011011011111011011010101
Mute    110101111101101110101011101011011110111011010101
Pst up    110101111101101110101011101010111110111101010101
Pst dn    110101111101101110101011010101011111111101010101
Source    110101111101101110101011101101111101101101010101
Trk up    110101111101101110101011101110111101101011010101
Trk dn    110101111101101110101011010111011111101011010101
Power    110101111101101110101011011101111110101101010101
Ent/Play    110101111101101110101011010101111111110101010101
Band/prog    110101111101101110101011011010111111011101010101


Note that the same series of 1's and 0's is at the start and end of each command, so here are the unique parts of each:


(Start)    110101111101101110101011

Vol Up    11011011110101101
Vol Dn    01101101111101101
Mute    10101101111011101
Pst up    10101011111011110
Pst dn    01010101111111110
Source    10110111110110110
Trk up    10111011110110101
Trk dn    01011101111110101
Power    01110111111010110
Ent/Play    01010111111111010
Band/prog    01101011111101110

(End)    1010101

So if "0" is low for 1000 us, and "1" is high for 500 us AND low for 500 us, how can I write the code ?!
Something like this (pseudo-code):

;(Start)    110101111101101110101011
 ; Vol Up    11011011110101101

check: select case key  case 1     ; volume down 
portb.7 = high
pauseus 500
portb.7 = low
pauseus 500  ' this is first "1"
portb.7 = high
pauseus 500
port.7 = low
pauseus 500 ' this is second "1"
... so on, so on ?!?

I need "a clue" ! Thanks in advance !!!