# Unicode ftp-8 TCP communications **URL:** \ **Category:** Ignition\ **Created:** [February 17, 2022, 3:29pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259 "2022-02-17T15:29:02Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 17, 2022, 3:29pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/1 "2022-02-17T15:29:02Z")
I’ve set up an EMPERIA in-line printer as a TCP device and communication was working well. Then they wanted to put up and down arrows in the text being printed. When I added an up arrow, the printer showed this as a ‘?’ so it was not getting the coding correct. The documents say it is utf-8 coding for the command language. In the printer, I set a variable up and put in an up arrow (U+2191 on their popup keyboard) and then read out the variable to Ign. What I got was ‘→ . If I copy that into the message I send to the printer, it does receive it as an arrow. I have tried some things I found online for encoding to utf-8 but nothing helps if I start with an actual arrow in the sting. I thought I would just put in a brute force decoding of the string before sending it and substitute in the characters it wants but I ran into a problem. This all happened on v8.0.13 so I updated to 8.1.14 last night. Now when I pull in a variable from the printer with a symbol, I actually see the symbol in the string, not the hieroglyphics I was getting before. Now I can’t even use that trick to get the ‘code’ for additional symbols. Can anyone point me in the right direction on how to encode these things properly? ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [February 17, 2022, 4:10pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/2 "2022-02-17T16:10:00Z")
How are you definining your strings, exactly? Python 2 requires that strings that contain non-ASCII be prefixed with `u` to mark them as unicode literals, e.g.: `variable = u"â†"` ---
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 17, 2022, 4:21pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/3 "2022-02-17T16:21:26Z")
I gave them a button to add arrows when setting the text to print. newMsg = oldMsg + u’\u2191’ This shows an up arrow in the string but when I look in the printer it is a ‘?’. if instead I do this: newMsg = oldMsg + ‘↑’ it shows up in the printer as an arrow, but the messages in my db look like ↑↑Q↑↑ which nobody will understand. If I know how to get from u’\u2191’ to ↑ I can put an interpreter behind the scene, just before sending it to the printer. But I can’t find anything online. I assume it represents the utf-8 ‘0xE2 0x86 0x91’ for an up arrow, but I’m not sure how to translate to that and substitute it into the string as a character. Brute force would work if I knew the down arrow version of ↑ but then I would still only be handle those two characters. Tomorrow, they will want something else. ---
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 17, 2022, 4:24pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/4 "2022-02-17T16:24:28Z")
FYI, even in the post, you are not seeing what I am really pasting in there. It looks like this while I am editing. ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/e/b/ebf0eae3d75cd6fda5d0ecedd40596a06d58c051.png) ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [February 17, 2022, 5:12pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/5 "2022-02-17T17:12:35Z")
Let’s step back a bit - can you share the full code you’re using to write to this printer, and/or any docs you might have from the printer? An encoding loss could be happening at multiple steps along the process. ---
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 17, 2022, 5:44pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/6 "2022-02-17T17:44:51Z")
There are a lot of steps that passes this thing around. A lot of this was an attempt to make it clear to future me. I have a loop that constantly polls for data. In that loop I also have a step that checks if manual commands are in que to be sent. In a button, I add this manual command to that que to set a variable in the printer. ```auto var = self.getChild("Dropdown").props.value val = self.getChild("TextField_0").props.text #val = unicode(val, 'utf-8') #val = u'\u2191' if len(val) > 0: newRow = ['VAR_SET', var, val] oldDS = system.tag.read('[default]Printers/MPERIA/Send/PollingMessages').value newDS = system.dataset.addRow(oldDS, newRow) system.tag.write('[default]Printers/MPERIA/Send/PollingMessages',newDS) ``` Then it is picked up in the while loop (in an asynchronous thread function defined in a button for now) and then calls a script to build the msg in the format that the printer expects. ```auto elif index == 5: # special command (manual stuff) # pull the command off of the top of the stack and send it # then remove the command. specialMsgs = system.tag.read('[default]Printers/MPERIA/Send/PollingMessages').value if specialMsgs.rowCount > 0: cmd = specialMsgs.getValueAt(0, 0) p1 = specialMsgs.getValueAt(0, 1) p2 = specialMsgs.getValueAt(0, 2) msg = MPERIA.msg(cmd, p1, p2) removed = system.dataset.deleteRow(specialMsgs, 0) system.tag.write('[default]Printers/MPERIA/Send/PollingMessages', removed) ``` The script in the project Library that builds the message: ```auto def msg(name, p1, p2): ACK = chr(6) # Acknowledge. Sent from the Controller to indicate the success of a # command sent to the Controller NAK = chr(21) # Negative acknowledge. Sent from the Controller to # indicate the failure of a command sent to the Controller. ETB = chr(23) # End of Transmission Block. Used as the final character in # all commands sent to the Controller, and as the end of data # sent from the Controller as a response to a command. ESC = chr(27) # Escape. Used as the starting character in all commands # sent to the Controller. FS = chr(28) # Unit Separator. Separates the command and arguments # sent to the Controller, and multiple responses sent from # the Controller as a response to a command. GS = chr(29) # Group Separator. Separates components of command # arguments into groups. RS = chr(30) # Record separator used to separate groups into records. US = chr(31) # Unit separator used to separate records into units. if p1 == None: msg = ESC + name + ETB elif p2 == None: msg = ESC + name + FS + p1 + ETB else: msg = ESC + name + FS + p1 + FS + p2 + ETB return msg ``` Then at the end of the loop ```auto if index > 0: sentTS = system.date.now() result = system.tag.writeBlocking(['[default]Printers/MPERIA/Writable'],[msg],1000) ``` [Command-Protocol-Manual-11.2.x.pdf](https://forum.inductiveautomation.com/uploads/short-url/4tpqkcddwyiUpO9KLaZHt9TtPY0.pdf) (407.1 KB) ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [February 17, 2022, 5:56pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/7 "2022-02-17T17:56:04Z")
I think you want to send your data to the `WritableBytes` tag, not the `Writeable` tag, which does some automatic encoding of data. If you’re trying to send specific data, that’s your best bet. ---
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 17, 2022, 5:57pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/8 "2022-02-17T17:57:47Z")
Update: I changed all of the chr() statements to unichr() and changed the final statement to write the tag as u = msg.encode(‘utf-8’) result = system.tag.writeBlocking([’[default]Printers/MPERIA/Writable’],[u],1000) and now I see a rectangle in the printer instead of the ‘?’ ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [February 17, 2022, 5:59pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/9 "2022-02-17T17:59:55Z")
A rectangle on the actual output label? That would (to me) indicate that the printer doesn’t have a font to use to render the character. ---
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 17, 2022, 6:19pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/10 "2022-02-17T18:19:14Z")
I assume you are correct. I’m going down the road you suggested for the writablebytes tag. When I created the device I was on an older version that did not have that feature so I didn’t even know that was an option. I’ll figure that out and mark as solution if it works. Thanks. ---
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 18, 2022, 4:20pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/11 "2022-02-18T16:20:49Z")
I am writing to the WritableBytes tag and I am getting the same results as before. I am converting to bytes using this: def toBarray(string): from java.lang import \* from org.python.core.util import StringUtil ``` #Convert string into a byte array bArr = StringUtil.toBytes(string) #Read string into byte array return bArr ``` I received a suggestion from MPERIA: Can you try this in Hex? 1B 76 61 72 5F 73 65 74 1C 76 61 72 31 1C **E2 86 91** 17 Seen as ascii: var\_setvar1 **↑** Here is a convert from u+ (2191) to UTF8 > I cannot figure out how to send his string of hex. I do know that when I put var\_setvar1 **↑** (with the ascii commands send as chr equivalents, ie unichr( 27) for ) I get array(‘b’, [27, 83, 69, 84, 95, 86, 65, 82, 28, 118, 97, 114, 49, 28, 63, 23]) is it possible to send the hex version to the writeablebytes tag? ---
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 18, 2022, 4:46pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/12 "2022-02-18T16:46:34Z")
Again, when I put in the strings to this forum they look fine until I post it. Here is what the blurb from MPERIA actually looks like: ![image](https://us1.discourse-cdn.com/inductiveautomation/original/3X/9/6/964008e1d2b94eb09708f82875a4af4f7dc007fb.png) ---
**Author:** ![JordanCClark](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/jordancclark/32/83362_2.png) [@JordanCClark](https://forum.inductiveautomation.com/u/JordanCClark)\ **Post date:** [February 18, 2022, 5:22pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/13 "2022-02-18T17:22:06Z")
try using the array library ```python import array stringIn = 'ABCD ↑' # For display purposes. Printing the array will return decimals. hexValues = [elem.encode('hex') for elem in stringIn] bArray = array.array('B', stringIn) print hexValues print bArray ``` Output: ```nohighlight ['41', '42', '43', '44', '20', 'e2', '86', '91'] array('B', [65, 66, 67, 68, 32, 226, 134, 145]) >>> ``` ---
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 18, 2022, 6:07pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/14 "2022-02-18T18:07:33Z")
> [@JordanCClark](#): > > `hexValues = [elem.encode('hex') for elem in stringIn]` Thank-you That may have put me on to something. This reflects how I am adding the arrows to my strings and the results I get using your code: import array a = u'\u2191' strIn = 'ABCD ' + a print strIn hexValues = [elem.encode('hex') for elem in strIn] print hexValues ABCD ↑ ['41', '42', '43', '44', '20', 'e28691'] I'm not sure if you just used the keyboard shortcut to type your up arrow, but that is not an option for this application. It appears the way I am doing it is causing an error. ---
**Author:** ![JordanCClark](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/jordancclark/32/83362_2.png) [@JordanCClark](https://forum.inductiveautomation.com/u/JordanCClark)\ **Post date:** [February 18, 2022, 7:36pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/15 "2022-02-18T19:36:36Z")
Try wrapping your string with a bytes() function ```python import array stringIn = bytes(u'ABCD \u2191') hexValues = [elem.encode('hex') for elem in stringIn] bArray = array.array('B', stringIn) print hexValues print bArray ``` ---
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 18, 2022, 7:56pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/16 "2022-02-18T19:56:02Z")
That worked. Now I know how to recreate the hex code they want me to send which is good progress but I don’t seem to be able to send that to the WriteableBytes tag of my TCP device. ---
**Author:** ![bebel](https://avatars.discourse-cdn.com/v4/letter/b/43a26b/32.png) [@bebel](https://forum.inductiveautomation.com/u/bebel)\ **Post date:** [February 18, 2022, 8:28pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/17 "2022-02-18T20:28:54Z")
Thanks Jordan, your suggestion led to the solution. I ended up not needing the hex values at all. I was sending my strings to be printed to a script to turn them into a byte array. def toBarray(string): from java.lang import \* from org.python.core.util import StringUtil ``` #Convert string into a byte array bArr = StringUtil.toBytes(string) #Read string into byte array return bArr ``` I was sending them with the line bArr = MPERIA.toBarray(msg) I changed it to this: bArr = MPERIA.toBarray(bytes(msg)) now it works. It seems strange to need to change a string to bytes before sending it to a script I found that is supposed to make bytes itself but I’m not poking it with a stick. ---
**Author:** ![JordanCClark](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/jordancclark/32/83362_2.png) [@JordanCClark](https://forum.inductiveautomation.com/u/JordanCClark)\ **Post date:** [February 18, 2022, 9:30pm UTC](https://forum.inductiveautomation.com/t/unicode-ftp-8-tcp-communications/56259/18 "2022-02-18T21:30:01Z")
Unicode can be annoying. I’ve spent many hours pulling my hair out over similar stuff. 🙄