I have gone through the VB_RFID3_Host_Sample2 application that comes with the EMDK and was trying to figure out the filtering and am having some trouble setting filters and I guess fully understanding them. I went through the help content and found a section on coding pre and post filters, along with RSSI filters. I was able(I think) to get the RSSI filters to work, but I am having some trouble with the pre and post. Below is the VB.net code I have added to the sample, that if I am understanding the help sample correctly, should not read tags starting with the character 6(hex 36). i have tags that have different id's and when i run this, it finds no tags, but when i clear the filter and try again, it reads all the tags. Basically what i did in the sample app was added another button that ran this code(along with another button to clear the filters), and then i just clicked the start reading and I expect tags without a start value of six to be read, but they are not.
Can someone assist me in figuring out the issue?
Dim filter As New PreFilters.PreFilter()
Dim tagMask As Byte() = New Byte(0) {&H36}
filter.AntennaID = 1
filter.TagPattern = tagMask
filter.TagPatternBitCount = CUInt(tagMask.Length) * 8
filter.BitOffset = 32
filter.MemoryBank = MEMORY_BANK.MEMORY_BANK_TID
filter.FilterAction = FILTER_ACTION.FILTER_ACTION_STATE_UNAWARE
filter.StateUnawareAction.Action = STATE_UNAWARE_ACTION.STATE_UNAWARE_ACTION_UNSELECT
' do not select the tags that match the pre-filter criteria
m_ReaderAPI.Actions.PreFilters.Add(filter)