in oscam reader give your cards a group ID
edit oscam.server
add group id to each reader, so reader one will have
group = 1
reader two will have
group = 2
reader three will have
group = 3
then add each user to the groups you want them to have access to.
edit oscam.user
for access to reader one add
[account]
user = test
pwd = pass
group = 1
monlevel = 0
caid = 0963
for access to reader one and two add
[account]
user = test
pwd = pass
group = 1,2
monlevel = 0
caid = 0963
for access to reader one, two and three add
[account]
user = test
pwd = pass
group = 1,2,3
monlevel = 0
caid = 0963
great if you want to give people access to certain cards