Help with creating a buffer of hex bytes from a string of hex words

General
6

So you realise you can inject a buffer from the inject node right?

But if you want to convert a string like "0201 0141 4000 0841 1E90 0000 0000 8203 45" to a buffer then you can do this...

msg.oldPayload = msg.payload; //save it for later debugging
var noSpaces = msg.payload.replace(/ /g, '');// remove spaces
msg.payload = Buffer.from(noSpaces, "hex"); //convert to buffer
return msg;

demo flow...

image
image588×622 21.3 KB

[{"id":"7b50a866.e6d048","type":"inject","z":"3ffdd389.c6e0bc","name":"fake mqtt","topic":"","payload":"0201 0141 4000 0841 1E90 0000 0000 8203 45","payloadType":"str","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":460,"y":540,"wires":[["bbea88eb.a001a8"]]},{"id":"bbea88eb.a001a8","type":"function","z":"3ffdd389.c6e0bc","name":"funky string to buffer","func":"msg.oldPayload = msg.payload; //save it for later debugging\nvar noSpaces = msg.payload.replace(/ /g, '');// remove spaces\nmsg.payload = Buffer.from(noSpaces, \"hex\"); //convert to buffer\nreturn msg;","outputs":1,"noerr":0,"x":650,"y":540,"wires":[["ddf36481.e0a718"]]},{"id":"ddf36481.e0a718","type":"debug","z":"3ffdd389.c6e0bc","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","x":830,"y":540,"wires":[]}]
3 Likes