From ed59d33f68233f6a73dee8e60634f10fb5a23920 Mon Sep 17 00:00:00 2001
From: Patrick Rohner <patrick.rohner@chemspeed.ch>
Date: Thu, 25 Mar 2021 08:34:22 +0100
Subject: [PATCH] Send full 8 byte of SDO message or full 4 byte of data
 according to CiA301 specification

---
 sdo/download.go | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/sdo/download.go b/sdo/download.go
index 4e05591..2db6098 100644
--- a/sdo/download.go
+++ b/sdo/download.go
@@ -56,6 +56,11 @@ func (download Download) Do(bus *can.Bus) error {
 		download.ObjectIndex.SubIndex,
 	}
 
+	// CiA301 Standard expects all bytes to be sent
+	for len(data) < 4 {
+		data = append(data, 0x0)
+	}
+
 	// Initiate
 	frame := canopen.Frame{
 		CobID: download.RequestCobID,