SDO datalength should be the bytes that does NOT contain data.

FabianPetersen · Oct 5, 2021 · 8c9d130 · 8c9d130
1 parent b2b6e0f
commit 8c9d130
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diff --git a/go.sum b/go.sum
@@ -1,4 +1,8 @@
+github.com/FabianPetersen/can v0.0.3 h1:AvNdtYRx/Qqd9ecVmPPk4/U27GT5kyvurtriWyASoMU=
+github.com/FabianPetersen/can v0.0.3/go.mod h1:K+0T7NSTiAhcH/zIYFPj4o256RKIwQ1Y/uHTC9MyK4I=
 github.com/brutella/can v0.0.1 h1:Rz+2Zuje3NT79daon8wPN9+VphH3/kl1DP8Dhf/k1NI=
 github.com/brutella/can v0.0.1/go.mod h1:NYDxbQito3w4+4DcjWs/fpQ3xyaFdpXw/KYqtZFU98k=
 golang.org/x/sys v0.0.0-20181213200352-4d1cda033e06 h1:0oC8rFnE+74kEmuHZ46F6KHsMr5Gx2gUQPuNz28iQZM=
 golang.org/x/sys v0.0.0-20181213200352-4d1cda033e06/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190429190828-d89cdac9e872 h1:cGjJzUd8RgBw428LXP65YXni0aiGNA4Bl+ls8SmLOm8=
+golang.org/x/sys v0.0.0-20190429190828-d89cdac9e872/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
diff --git a/sdo/download.go b/sdo/download.go
@@ -50,8 +50,9 @@ func (download Download) Do(bus *can.Bus) error {
 		n = byte(size)
 	}
 
+	// If valid "n" indicates the number of bytes in d that do not contain data. Hence 4 -
 	bytes := []byte{
-		byte(ClientIntiateDownload | e | s | ((int(n) << 2) & TransferMaskSize)),
+		byte(ClientIntiateDownload | e | s | ((4 - (int(n) << 2)) & TransferMaskSize)),
 		download.ObjectIndex.Index.B0, download.ObjectIndex.Index.B1,
 		download.ObjectIndex.SubIndex,
 	}