diff --git a/linux/boardtest/SpiTestClass.cpp b/linux/boardtest/SpiTestClass.cpp
index 575bd6cb..91e8893c 100644
--- a/linux/boardtest/SpiTestClass.cpp
+++ b/linux/boardtest/SpiTestClass.cpp
@@ -555,9 +555,10 @@ void SpiTestClass::max1227PlPcduTest(int fd) {
     uint8_t n = 11;
     size_t tmpSz = spiTransferStruct[0].len;
     max1227::prepareExternallyClockedRead0ToN(sendBuffer.data(), n, tmpSz);
-    max1227::prepareExternallyClockedTemperatureRead(sendBuffer.data() + spiTransferStruct[0].len,
-                                                     tmpSz);
     spiTransferStruct[0].len = tmpSz;
+    size_t dummy = 0;
+    max1227::prepareExternallyClockedTemperatureRead(sendBuffer.data() + spiTransferStruct[0].len,
+                                                     dummy);
     // + 1 to account for temp conversion byte
     spiTransferStruct[0].len += 1;
     transfer(fd, gpioIds::PLPCDU_ADC_CS);