# Long char messages

**URL:** <https://forum.opencyphal.org/t/long-char-messages/832>\
**Category:** Applications & Usage\
**Created:** [May 14, 2020, 5:54pm UTC](https://forum.opencyphal.org/t/long-char-messages/832 "2020-05-14T17:54:39Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![phoenixcomm](https://forum.opencyphal.org/user_avatar/forum.opencyphal.org/phoenixcomm/32/486_2.png) [@phoenixcomm](https://forum.opencyphal.org/u/phoenixcomm)\
**Post date:** [May 14, 2020, 5:54pm UTC](https://forum.opencyphal.org/t/long-char-messages/832/1 "2020-05-14T17:54:39Z")

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Hi how can I send 8-byte or longer char strings?? ie:  
SYSTEM  
TEST 1 OK  
This message is sent from the system to the DIGITAL FUEL DISPLAY the display is composed of 2 x 8 smart LED display hdps-2111 which can be addressed separately. I can address all eight displays separately. So maybe:  
display 0/1/2 where 0 is a command?  
char 0 - 7  
alpha letter  
ie to write to the entire display would take 16 writes ☹  
plus I have to be able to send commands to it like reset and clear  
or  
can I create a “custom” for this device which will take 8 chars at a time.

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**Author:** ![pavel.kirienko](https://forum.opencyphal.org/user_avatar/forum.opencyphal.org/pavel.kirienko/32/9_2.png) [@pavel.kirienko](https://forum.opencyphal.org/u/pavel.kirienko)\
**Post date:** [May 14, 2020, 10:22pm UTC](https://forum.opencyphal.org/t/long-char-messages/832/2 "2020-05-14T22:22:24Z")

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You can define your own type:

```auto
uint8[<=2*8] text

```

And assign a dedicated subject per display. Alternatively, you can throw a key field in there and share the same subject for all displays, depending on your objectives:

```auto
uint16 display_id
uint8[<=2*8] text

```

Or you could just use the standard type [`uavcan.primitive.String`](https://github.com/UAVCAN/public_regulated_data_types/blob/master/uavcan/primitive/String.1.0.uavcan).

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<div class="post-metadata">

**Author:** ![phoenixcomm](https://forum.opencyphal.org/user_avatar/forum.opencyphal.org/phoenixcomm/32/486_2.png) [@phoenixcomm](https://forum.opencyphal.org/u/phoenixcomm)\
**Post date:** [May 17, 2020, 3:49pm UTC](https://forum.opencyphal.org/t/long-char-messages/832/3 "2020-05-17T15:49:57Z")

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Thank you!!