fix slip protocol argument padding

README.adoc

@@ -24,8 +24,8 @@ but significantly reqritten and no longer protocol compatible, thanks to tuanpmt
 inspiration!
 
 Many thanks to https://github.com/brunnels for contributions in particular around the espduino
-functionality. Thank you also to https://github.com/susisstrolch and https://github.com/bc547 for
-additional contributions!
+functionality. Thank you also to https://github.com/susisstrolch, https://github.com/bc547,
+and https://github.com/katast for additional contributions!
 
 [float]
 Table of Contents

cmd/cmd.c

@@ -63,7 +63,7 @@ cmdResponseBody(const void *data, uint16_t len) {
   cmdProtoWriteBuf(data, len);
   resp_crc = crc16_data(data, len, resp_crc);
 
-  uint16_t pad = (4-(len&3))&3; // get to multiple of 4
+  uint16_t pad = (4-((len+2)&3))&3; // get to multiple of 4
   if (pad > 0) {
     uint32_t temp = 0;
     cmdProtoWriteBuf((uint8_t*)&temp, pad);