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I built a tristate slave sopc component and I'm using it to access external memory.
I have two problems: The first one, I found it was already discussed in following post: http://www.alteraforum.com/forum/showthread.php?p=77491 My external device is 16bit wide but any IORD call results in two slave accesses, as complained in the linked post At the moment I must define the tristate slave with a fake 32bit data port and leave the upper bits unconnected. I ask if in the meantime the bug has been solved or if a patch is available (I'm using 9.0 sp2). The second issue is about tristate slave configuration. I can't add wait states to the read operation. In the tcl component definition I wrote:# Interface avalon_tristate_slave
add_interface "avalon_tristate_slave" "avalon_tristate" "slave" "asynchronous"
set_interface_property "avalon_tristate_slave" "isNonVolatileStorage" "false"
set_interface_property "avalon_tristate_slave" "readLatency" "0"
set_interface_property "avalon_tristate_slave" "holdTime" "1"
set_interface_property "avalon_tristate_slave" "printableDevice" "false"
set_interface_property "avalon_tristate_slave" "readWaitTime" "2"
set_interface_property "avalon_tristate_slave" "setupTime" "1"
set_interface_property "avalon_tristate_slave" "writeWaitTime" "1"
set_interface_property "avalon_tristate_slave" "timingUnits" "Cycles"
set_interface_property "avalon_tristate_slave" "minimumUninterruptedRunLength" "1"
set_interface_property "avalon_tristate_slave" "activeCSThroughReadLatency" "false"
set_interface_property "avalon_tristate_slave" "isMemoryDevice" "true"
set_interface_property "avalon_tristate_slave" "writeWaitStates" "1"
set_interface_property "avalon_tristate_slave" "maximumPendingReadTransactions" "0"
clk=100MHz, then I assumed that readWaitTime=2 should lengthen the read strobe to 30ns. This is correctly shown in the waveform in Component Editor (Interface section). But measuring with oscilloscope I always have a 20ns value. Any ideas? Regards
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