diff --git a/SpiNNaker-front-end/src/main/java/uk/ac/manchester/spinnaker/front_end/dse/HostExecuteDataSpecification.java b/SpiNNaker-front-end/src/main/java/uk/ac/manchester/spinnaker/front_end/dse/HostExecuteDataSpecification.java
index 64cb24ea25..3be4e65fd0 100644
--- a/SpiNNaker-front-end/src/main/java/uk/ac/manchester/spinnaker/front_end/dse/HostExecuteDataSpecification.java
+++ b/SpiNNaker-front-end/src/main/java/uk/ac/manchester/spinnaker/front_end/dse/HostExecuteDataSpecification.java
@@ -125,7 +125,7 @@ protected void writeRegion(HasCoreLocation core,
 			var address = baseAddress;
 			for (var buf : content) {
 				var data = buf.duplicate();
-				var size = buf.remaining();
+				var size = data.remaining();
 				txrx.writeMemory(core.getScampCore(), address, data);
 				address.add(size);
 			}