> For the complete documentation index, see [llms.txt](https://sandbox-docs.verifone.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sandbox-docs.verifone.com/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___l_e_d.md). # LED control [Modules](#groups) | [Data Structures](#nested-classes) | [Macros](#define-members) | [Typedefs](#typedef-members) | [Functions](#func-members) Collaboration diagram for LED control: ![](/files/hEoi2d7t0r2onfz8jDoH) | | | | ------- | -------------------------------------------------------------------------------------------------------------------------------------------------- | | Modules | | | | [Defines for LED IDs](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___l_e_d/group___a_d_k___l_e_d___d_e_f_i_n_e_s___i_d_s.md) | | |

LED numbers in EMV\_CTLS\_LED()

| | | [Defines for LED states](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___l_e_d/group___a_d_k___l_e_d___d_e_f_i_n_e_s___s_t_a_t_e_s.md) | | |

LED states to be used in EMV\_CTLS\_LED()

| | | [Defines for LED modes](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___l_e_d/group___a_d_k___l_e_d___d_e_f_i_n_e_s___m_o_d_e_s.md) | | |

LED modes to be used in EMV\_CTLS\_LED\_SetMode()

| | | [Defines for LED handling](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___l_e_d/group___a_d_k___l_e_d___d_e_f_i_n_e_s.md) | | |

LED numbers and modes to be used in EMV\_CT\_LED()

| | | | | --------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Data Structures | | | struct | [EMV\_CTLS\_LED\_COLORS\_STRUCT](#struct_e_m_v___c_t_l_s___l_e_d___c_o_l_o_r_s___s_t_r_u_c_t) | | |

Data structure for LED colors. Input for EMV\_CTLS\_LED\_ConfigDesign\_Extended() More...

| | struct | [EMV\_CTLS\_LED\_CONFIG\_STRUCT](#struct_e_m_v___c_t_l_s___l_e_d___c_o_n_f_i_g___s_t_r_u_c_t) | | |

Data structure for LED configuration. Input for EMV\_CTLS\_LED\_ConfigDesign\_Extended() More...

| | | | | ------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Macros | | | #define | [EMV\_CTLS\_LED\_SHAPE\_RECTANGLE](#ga7c2b396064512cb0467af8f9af3a4a3f) 0 | | |

Data structure for LED colors. Used in EMV\_CTLS\_LED\_CONFIG\_STRUCT::shape. More...

| | | | | ------------------------------------------------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Typedefs | | | typedef struct [EMV\_CTLS\_LED\_COLORS\_STRUCT](#struct_e_m_v___c_t_l_s___l_e_d___c_o_l_o_r_s___s_t_r_u_c_t) | [EMV\_CTLS\_LED\_COLORS](#gadd614d38c9bc0aebba3090672eafbe37) | | |

Data structure for LED colors. Input for EMV\_CTLS\_LED\_ConfigDesign\_Extended() More...

| | typedef struct [EMV\_CTLS\_LED\_CONFIG\_STRUCT](#struct_e_m_v___c_t_l_s___l_e_d___c_o_n_f_i_g___s_t_r_u_c_t) | [EMV\_CTLS\_LED\_CONFIG](#ga925c2fa10d6fa315adf31f35a265e130) | | |

Data structure for LED configuration. Input for EMV\_CTLS\_LED\_ConfigDesign\_Extended() More...

| | | | | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Functions | | | [DLL\_CLC](/s-adk-5.1-programmers-guide/readme/files/dir_f2a776acea245b054b8e462971041f2d/dir_11dd2805a17b345163bcda0bbda50405/dir_47d451f83ac668365bf475eea7a5e317/dir_ba55f31769dc4aed085c5be441e39791/_e_m_v___c_t_l_s___interface_8h.md#a0c075561565f443dd054da7871da8462) unsigned char | [EMV\_CTLS\_LED\_SetMode](#ga62eb0e6232dad59e94b75205493fa06d) (unsigned char ucLedMode) | | |

Set mode of LED control. More...

| | [DLL\_CLC](/s-adk-5.1-programmers-guide/readme/files/dir_f2a776acea245b054b8e462971041f2d/dir_11dd2805a17b345163bcda0bbda50405/dir_47d451f83ac668365bf475eea7a5e317/dir_ba55f31769dc4aed085c5be441e39791/_e_m_v___c_t_l_s___interface_8h.md#a0c075561565f443dd054da7871da8462) unsigned char | [EMV\_CTLS\_LED](#gabd80a7d1c3dbc5604604b02c20620f51) (unsigned char ucLedId, unsigned char ucLedState) | | |

Switch on LED. More...

| | [DLL\_CLC](/s-adk-5.1-programmers-guide/readme/files/dir_f2a776acea245b054b8e462971041f2d/dir_11dd2805a17b345163bcda0bbda50405/dir_47d451f83ac668365bf475eea7a5e317/dir_ba55f31769dc4aed085c5be441e39791/_e_m_v___c_t_l_s___interface_8h.md#a0c075561565f443dd054da7871da8462) unsigned char | [EMV\_CTLS\_LED\_ConfigDesign](#gaabbf98fcb94592b96bee2c680bfccee9) (unsigned short width, unsigned short height, unsigned char \*color\_off, unsigned char \*color\_on, unsigned short xRegion, unsigned short yRegion, unsigned short wRegion, unsigned short hRegion) \_\_attribute((deprecated)) | | |

Configure the desing for the framebuffer LEDs used for virtual CTLS LEDs
Only required when using virtual LEDs.
. More...

| | [DLL\_CLC](/s-adk-5.1-programmers-guide/readme/files/dir_f2a776acea245b054b8e462971041f2d/dir_11dd2805a17b345163bcda0bbda50405/dir_47d451f83ac668365bf475eea7a5e317/dir_ba55f31769dc4aed085c5be441e39791/_e_m_v___c_t_l_s___interface_8h.md#a0c075561565f443dd054da7871da8462) unsigned char | [EMV\_CTLS\_LED\_ConfigDesign\_Extended](#ga8b647b4c8f995795b250bd2df10c2796) (const [EMV\_CTLS\_LED\_CONFIG](#ga925c2fa10d6fa315adf31f35a265e130) \*led\_config) \_\_attribute((deprecated)) | | |

Configure the design for the framebuffer LEDs used for virtual CTLS LEDs
Only required when using virtual LEDs.
. More...

| ### DetailedDescription *** ### DataStructure Documentation ### EMV\_CTLS\_LED\_COLORS\_STRUCT struct EMV\_CTLS\_LED\_COLORS\_STRUCT Data structure for LED colors. Input for [EMV\_CTLS\_LED\_ConfigDesign\_Extended()](#ga8b647b4c8f995795b250bd2df10c2796) | | | | | ---------------- | ----------- | ------------------------------------------------------------------------------------------------------------------------ | | Data Fields | | | | unsigned char \* | colors | Array of colors, each color is 3 bytes (24 bit RGB), so length of array must be num\_colors \* 3. | | unsigned char | num\_colors | number of different colors; set to 1 if all LEDs should have the same color, set to 4 if all LEDs have different colors. | ### EMV\_CTLS\_LED\_CONFIG\_STRUCT struct EMV\_CTLS\_LED\_CONFIG\_STRUCT Data structure for LED configuration. Input for [EMV\_CTLS\_LED\_ConfigDesign\_Extended()](#ga8b647b4c8f995795b250bd2df10c2796) Collaboration diagram for EMV\_CTLS\_LED\_CONFIG\_STRUCT: ![Collaboration graph](/files/IkTIkWMrIIiZezjZNIy5) \[[legend](/s-adk-5.1-programmers-guide/graph_legend.md)] | | | | | ------------------------------------------------------------- | -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | Data Fields | | | | unsigned char \* | bg\_color | background color, only used if shape == EMV\_CTLS\_LED\_SHAPE\_CIRCLE | | [EMV\_CTLS\_LED\_COLORS](#gadd614d38c9bc0aebba3090672eafbe37) | colors\_off | colors of LEDs in off state | | [EMV\_CTLS\_LED\_COLORS](#gadd614d38c9bc0aebba3090672eafbe37) | colors\_on | colors of LEDs in on state | | unsigned char \* | options | RFU, set to NULL. | | unsigned short | region\_height | height of the LED Region | | unsigned short | region\_width | width of the LED Region | | unsigned short | region\_x | x coordinate of the LED Region (upper left corner) | | unsigned short | region\_y | y coordinate of the LED Region (upper left corner) | | unsigned char | shape | shape of LEDs, one of EMV\_CTLS\_LED\_SHAPE\_RECTANGLE, EMV\_CTLS\_LED\_SHAPE\_CIRCLE | | unsigned short \* | shape\_params | if shape == EMV\_CTLS\_LED\_SHAPE\_RECTANGLE: first value: width of LED, second value: height of LED; if shape == EMV\_CTLS\_LED\_SHAPE\_CIRCLE: first value: radius of LED (width=height=2\*radius+1) | ### MacroDefinition Documentation ### EMV\_CTLS\_LED\_SHAPE\_RECTANGLE \#define EMV\_CTLS\_LED\_SHAPE\_RECTANGLE 0 Data structure for LED colors. Used in [EMV\_CTLS\_LED\_CONFIG\_STRUCT::shape](#a9d7f77334f11d266e824cb9b0ec6871e). rectangular LEDs ### TypedefDocumentation ### EMV\_CTLS\_LED\_COLORS typedef struct \[EMV\_CTLS\_LED\_COLORS\_STRUCT]\(#struct\_e\_m\_v\_\_\_c\_t\_l\_s\_\_\_l\_e\_d\_\_\_c\_o\_l\_o\_r\_s\_\_\_s\_t\_r\_u\_c\_t) \[EMV\_CTLS\_LED\_COLORS]\(#gadd614d38c9bc0aebba3090672eafbe37) Data structure for LED colors. Input for [EMV\_CTLS\_LED\_ConfigDesign\_Extended()](#ga8b647b4c8f995795b250bd2df10c2796) ### EMV\_CTLS\_LED\_CONFIG typedef struct \[EMV\_CTLS\_LED\_CONFIG\_STRUCT]\(#struct\_e\_m\_v\_\_\_c\_t\_l\_s\_\_\_l\_e\_d\_\_\_c\_o\_n\_f\_i\_g\_\_\_s\_t\_r\_u\_c\_t) \[EMV\_CTLS\_LED\_CONFIG]\(#ga925c2fa10d6fa315adf31f35a265e130) Data structure for LED configuration. Input for [EMV\_CTLS\_LED\_ConfigDesign\_Extended()](#ga8b647b4c8f995795b250bd2df10c2796) ### FunctionDocumentation ### EMV\_CTLS\_LED() [DLL\_CLC](/s-adk-5.1-programmers-guide/readme/files/dir_f2a776acea245b054b8e462971041f2d/dir_11dd2805a17b345163bcda0bbda50405/dir_47d451f83ac668365bf475eea7a5e317/dir_ba55f31769dc4aed085c5be441e39791/_e_m_v___c_t_l_s___interface_8h.md#a0c075561565f443dd054da7871da8462) unsigned char EMV\_CTLS\_LED Switch on LED. Using this function instead of ADK-GUI API (\[ADK-GUI Programmers Guide]) may be useful as * ADK-GUI does not control physical (hardware) LEDs * in standard mode the SDI has control of the UI * blinking functionality for 1st LED can be used * application can use common code for terminals with and without physical LEDs * "end of transaction" handling (e.g. [CONTACTLESS\_LED\_HANDLE\_EOT\_SUCCESS](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___l_e_d/group___a_d_k___l_e_d___d_e_f_i_n_e_s___s_t_a_t_e_s.md#ga4bab0d93ec30b5127e214c20ef0dd5a3)) can be used for domestic cards Transport tags used for serialization: [CLA\_LED](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___s_e_r_i_a_l_i_z_a_t_i_o_n___c_t/group___a_d_k___t_r_a_n_s_p_o_r_t___t_a_g_s___c_t.md#gad1c3412f36620771889c9691889f80b1) [INS\_LED\_SWITCH](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___s_e_r_i_a_l_i_z_a_t_i_o_n___c_t/group___a_d_k___t_r_a_n_s_p_o_r_t___t_a_g_s___c_t.md#ga0c455b1cdcb1ad1513e54c823f1d07a8) [Explanation in programmers guide](/s-adk-5.1-programmers-guide/readme/system_overview/pg_all_components/pg_emv_contactless_users_guide.md#anchor_emv_ctls_leds_switch_leds) #### Author GSS R\&D Germany **Parameters** \[in] **ucLedId** LED number, see Defines for LED IDsThis is a combination of LEDs. (use binary bitwise inclusive OR of LED-Bit-masks defined in Defines for LED IDs)Bits which are not defined in Defines for LED IDs should be 0. They are reserved for future use and will be ignored. \[in] **ucLedState** LED state, see Defines for LED states #### Returns [EMV\_ADK\_OK](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga1456bb13b42906927f8a8942169b62e7): success [EMV\_ADK\_TLV\_BUILD\_ERR](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga4837e54c589150debdef49afb8f9b5db): TLV processing problem [EMV\_ADK\_INTERNAL](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#gab0e8158b5e7019f0da44c5cbc37bae3d): internal communication problem, illegal file content, memory allocation [EMV\_ADK\_NOT\_ALLOWED](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga3a1d800696b9d7a86c0e39068d3fde57): function not allowed in a concurrent call or not allowed within callback ### EMV\_CTLS\_LED\_ConfigDesign() [DLL\_CLC](/s-adk-5.1-programmers-guide/readme/files/dir_f2a776acea245b054b8e462971041f2d/dir_11dd2805a17b345163bcda0bbda50405/dir_47d451f83ac668365bf475eea7a5e317/dir_ba55f31769dc4aed085c5be441e39791/_e_m_v___c_t_l_s___interface_8h.md#a0c075561565f443dd054da7871da8462) unsigned char EMV\_CTLS\_LED\_ConfigDesign Configure the desing for the framebuffer LEDs used for virtual CTLS LEDs **Only required when using virtual LEDs.** . [**Deprecated:**](/s-adk-5.1-programmers-guide/readme/deprecated.md#_deprecated000049) The direct framebuffer approach is deprecated - use LED callbacks and LED-API from ADK-GUIPRT instead Transport tags used for serialization: [CLA\_LED](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___s_e_r_i_a_l_i_z_a_t_i_o_n___c_t/group___a_d_k___t_r_a_n_s_p_o_r_t___t_a_g_s___c_t.md#gad1c3412f36620771889c9691889f80b1) [INS\_LED\_CONF\_DESIGN](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t_l_s/group___a_d_k___s_e_r_i_a_l_i_z_a_t_i_o_n___c_t_l_s/group___a_d_k___t_r_a_n_s_p_o_r_t___t_a_g_s___c_t_l_s.md#gac4b89905db7b0371dba0ec2a42f73071) #### Author GSS R\&D Germany **Parameters** \[in] **width** width of the rectangular LED \[in] **height** height of the rectangular LED \[in] **color\_off** off color (24bit) (usually black == 0) \[in] **color\_on** color of the LED (24bit) \[in] **xRegion** x coordinate of the LED Region (upper left corner) \[in] **yRegion** y coordinate of the LED Region (upper left corner) \[in] **wRegion** width of the LED Region \[in] **hRegion** height of the LED Region #### Returns [EMV\_ADK\_OK](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga1456bb13b42906927f8a8942169b62e7): success [EMV\_ADK\_TLV\_BUILD\_ERR](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga4837e54c589150debdef49afb8f9b5db): TLV processing problem [EMV\_ADK\_INTERNAL](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#gab0e8158b5e7019f0da44c5cbc37bae3d): internal communication problem, illegal file content, memory allocation [EMV\_ADK\_PARAM](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga89c11346e5e636e7c9d42c6a772674bf): bad color\_off or color\_on input params [EMV\_ADK\_NOT\_ALLOWED](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga3a1d800696b9d7a86c0e39068d3fde57): function not allowed in a concurrent call or not allowed within callback [EMV\_ADK\_NO\_EXEC](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga7ffea44a30b0451d393487eae4035b4e): terminal is not VOS or VOS2 ### EMV\_CTLS\_LED\_ConfigDesign\_Extended() [DLL\_CLC](/s-adk-5.1-programmers-guide/readme/files/dir_f2a776acea245b054b8e462971041f2d/dir_11dd2805a17b345163bcda0bbda50405/dir_47d451f83ac668365bf475eea7a5e317/dir_ba55f31769dc4aed085c5be441e39791/_e_m_v___c_t_l_s___interface_8h.md#a0c075561565f443dd054da7871da8462) unsigned char EMV\_CTLS\_LED\_ConfigDesign\_Extended Configure the design for the framebuffer LEDs used for virtual CTLS LEDs **Only required when using virtual LEDs.** . [**Deprecated:**](/s-adk-5.1-programmers-guide/readme/deprecated.md#_deprecated000050) The direct framebuffer approach is deprecated - use LED callbacks and LED-API from ADK-GUIPRT instead Coloured LEDs should be used together with [INPUT\_CTLS\_TRM\_FLOWOPT\_LED\_EP\_OPTION\_2](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___c_o_n_f_i_g_u_r_a_t_i_o_n___c_t_l_s/group___d_e_f___c_o_n_f___t_e_r_m___c_t_l_s/group___t_e_r_m___f_l_o_w___o_p_t_i_o_n_s.md#ga2c5f919832e3ec1d5c5054291b27191c). Transport tags used for serialization: [CLA\_LED](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___s_e_r_i_a_l_i_z_a_t_i_o_n___c_t/group___a_d_k___t_r_a_n_s_p_o_r_t___t_a_g_s___c_t.md#gad1c3412f36620771889c9691889f80b1) [INS\_LED\_CONF\_DESIGN](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t_l_s/group___a_d_k___s_e_r_i_a_l_i_z_a_t_i_o_n___c_t_l_s/group___a_d_k___t_r_a_n_s_p_o_r_t___t_a_g_s___c_t_l_s.md#gac4b89905db7b0371dba0ec2a42f73071) #### Author GSS R\&D Germany **Parameters** \[in] **led\_config** LED configuration, see EMV\_CTLS\_LED\_CONFIG\_STRUCT #### Returns `0` ... okay `!=0` ... error ### EMV\_CTLS\_LED\_SetMode() [DLL\_CLC](/s-adk-5.1-programmers-guide/readme/files/dir_f2a776acea245b054b8e462971041f2d/dir_11dd2805a17b345163bcda0bbda50405/dir_47d451f83ac668365bf475eea7a5e317/dir_ba55f31769dc4aed085c5be441e39791/_e_m_v___c_t_l_s___interface_8h.md#a0c075561565f443dd054da7871da8462) unsigned char EMV\_CTLS\_LED\_SetMode Set mode of LED control. {% hint style="info" %} For special needs only. Usage of [EMV\_CTLS\_LED()](#gabd80a7d1c3dbc5604604b02c20620f51) is possible without using this function. {% endhint %} Before starting a contactless transaction, it must be set to `CONTACTLESS_LED_MODE_EMV`. In case the application wants to switch LEDs independent of EMV, it may set the mode to `CONTACTLESS_LED_MODE_API`. The status is saved when switching to EMV mode at the beginning of a transaction and restored once switching back to API mode. This use case is optional. By default, the application may simply use the EMV mode. In EMV mode, the application has even the ability to change the LEDs after the end of the transaction (e.g. switch on idle blinking). Transport tags used for serialization: [CLA\_LED](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___s_e_r_i_a_l_i_z_a_t_i_o_n___c_t/group___a_d_k___t_r_a_n_s_p_o_r_t___t_a_g_s___c_t.md#gad1c3412f36620771889c9691889f80b1) [INS\_LED\_MODE](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t_l_s/group___a_d_k___s_e_r_i_a_l_i_z_a_t_i_o_n___c_t_l_s/group___a_d_k___t_r_a_n_s_p_o_r_t___t_a_g_s___c_t_l_s.md#ga62d51f45ace79bf1afa60498d84b17ad) #### Author GSS R\&D Germany **Parameters** \[in] **ucLedMode** LED mode, see Defines for LED modes #### Returns [EMV\_ADK\_OK](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga1456bb13b42906927f8a8942169b62e7): success [EMV\_ADK\_TLV\_BUILD\_ERR](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga4837e54c589150debdef49afb8f9b5db): TLV processing problem [EMV\_ADK\_INTERNAL](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#gab0e8158b5e7019f0da44c5cbc37bae3d): internal communication problem, illegal file content, memory allocation [EMV\_ADK\_NOT\_ALLOWED](/s-adk-5.1-programmers-guide/readme/modules/group___a_d_k___g_e_n_e_r_a_l___c_t/group___a_d_k___r_e_t___c_o_d_e___c_t.md#ga3a1d800696b9d7a86c0e39068d3fde57): function not allowed in a concurrent call or not allowed within callback --- # Agent Instructions This documentation is published with GitBook. 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