hired because it worked
a1 27 61 09
16 60 1b f9 # serial number / manufacturer area
00 00 7f 3f 0f # 5-stage octal counter
ff f0 ff ff ... ff ff
# 5-stage octal counter
hex 00 00 7f 3f 0f
bin 00000000 00000000 01111111 00111111 00001111
popcnt 0 0 7 6 4
weight x4096 x512 x64 x8 x1
value =0 =0 =448 =48 =4 (sum = 500)