I=action.bin
O=action_128.rom
i=0
z=""
while [[ $i -lt 512 ]]; do 
z+=FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
(( i = i + 1 ))
done
function out8k() {
echo "$z" | xxd -r -ps
}

echo -n >$O
dd iseek=0 if=$I of=/dev/stdout bs=4096 count=1 >>$O
dd iseek=3 if=$I of=/dev/stdout bs=4096 count=1 >>$O

for t in 1 2 ; do out8k >>$O ; done

dd iseek=1 if=$I of=/dev/stdout bs=4096 count=1 >>$O
dd iseek=3 if=$I of=/dev/stdout bs=4096 count=1 >>$O

dd iseek=2 if=$I of=/dev/stdout bs=4096 count=1 >>$O
dd iseek=3 if=$I of=/dev/stdout bs=4096 count=1 >>$O

for t in 1 2 3  1 2 3 4 5 6 7 8 ; do out8k >>$O ; done