OSP Telegrams aoosp

Library "OSP Telegrams aoosp", usually abbreviated to "aoosp", is one of the aolibs; short for Arduino OSP libraries from ams-OSRAM. This suite implements support for chips that use the Open System Protocol, like the AS1163 ("SAID") or the OSIRE E3731i ("RGBi"). The landing page for the aolibs is on GitHub.

Introduction

Library aoosp is at the heart of the dependency graph.

It contains functions to construct telegrams (byte arrays) to be send to OSP nodes. It also contains functions to destruct response telegrams received back from OSP nodes. Both functions are hidden behind the API; the API allows sending and receiving telegrams, which involves constructing, transmit-out, transmit-in and destructing.

For telegram transmission this library relies on a communications layer, typically aospi. That library expects a board like the OSP32 board in the evaluation kit.

Examples

This library comes with the following examples. You can find them in the Arduino IDE via File > Examples > OSP Telegrams aoosp > ...:

• aoosp_crc (source)
  This demo computes the CRC of a telegram (byte buffer). Once to compute the required CRC for sending a command. Once to check the CRC in an incoming response.

• aoosp_min (source)
  This "blinky" demo sends a minimal set of OSP telegrams that light up an LED connected to a SAID channel. Once using BiDir, once using Loop. Then repeats.

• aoosp_topo (source)
  This demo scans all nodes and prints out the chain configuration: comms for both SIOs, direction, power state, number of RGBs and I2Cs.

• aoosp_cur (source)
  This demo configures channel 1 of node 001 to use a high drive current, and it configures channel 1 of node 002 to use a low drive current. Next it broadcasts setpwm with max brightness (FFFF FFFF FFFF). This results in the two white lights with different brightness.

• aoosp_error (source)
  This demo shows how error handling works in SAID. The STAT register has error flags denoting which errors occurred. The SETUP register has flags denoting which errors need to be trapped. When an error occurs (is flagged in STAT) whose trap bit is set (in SETUP), then the error is handled by switching to SLEEP state. This switches off the PWMs.

• aoosp_group (source)
  This demo groups two SAIDs, then sends PWM commands to that group. One command to switch the group to red, one command to switch the group to green. Then repeats.

• aoosp_i2c (source)
  This demo first performs an I2C scan using the I2C bridge in a SAID. Then it issues I2C read and write transactions to an 256 byte EEPROM memory. The EEPROM is assumed to have I2C device address 0x50 and to be connected to the first SAID. Finally it polls the INT line and shows its status on SAID1.RGB0.

• aoosp_i2c12 (source)
  This demo shows how to read and write to an I2C devices using 12 bits mode. The demo assumes an empty 8k byte EEPROM (i.e. filled with FFs) is connected to the I2C port of the OSP32. The demo resets and initializes the OSP chain, configures the SAID on the OSP32 board for 12 bits mode, then writes five bytes to location 0x12E of the EEPROM. After that a memory dump is made. To clean up, the five bytes are reset to 0xFF again.

• aoosp_sync (source)
  This demo shows how to use the SYNC feature; a feature that switches on all LEDs at the same time. We first enable (channels) of nodes for SYNC (AOOSP_CURCHN_FLAGS_SYNCEN). Next, set those channels to some PWM value. Finally we issue a SYNC by broadcasting the SYNC telegram. This makes all (channels) of all nodes that are configured for SYNC to activate their PWM settings.

  It is also possible to pulse a pin as hardware SYNC. The demo has that as secondary feature, but The OTP password must be known and enabled for this to work.

• aoosp_ledst (source)
  This demo shows the behavior of LOS (LED Open Short) status which is obtained via the telegram readledst[chn].

• aoosp_adcled (source)
  This sketch uses the ADC inside the SAID to measure the forward voltage of the LEDs connected to it.

• aoosp_adcpot (source)
  This sketch configures a SAID pin as ADC input (instead of driving an LED). Attached to this pad is a potentiometer to vary the voltage. The measured voltage is printed on Serial and mapped to a color (red to blue) of an RGB LED.

• aoosp_time (source)
  This demo sends a series of telegrams. The series originally comes from aomw_topo_build. We measure how long it takes to run that series. Once we use the high level aoosp API, and once we use low level aospi API. The conclusion is that the software overhead can be ignored.

• aoosp_cluster (source)
  This demo shows how clustering works - even on the evaluation kit, where none of the SAIDs is wired for clustering. The OTP password must be known and enabled or this example will not work.

• aoosp_tinfo (source)
  This demo shows how to use the ASKTINFO feature. The asktinfo telegram collects the minimum and maximum temperature over an OSP chain using a mechanism called "serial cast". This demo also explains serial cast.

• aoosp_otp (source)
  This demo reads and writes from/to the mirror of the OTP (one time programmable memory) of a SAID. The OTP password must be known and enabled or this example will not work.

• aoosp_otpburn (source)
  This demo burns a bit in the OTP (one time programmable memory) of a SAID. The demo aoosp_otp.ino only writes in the non-persistent OTP mirror, this demo actually updates the OTP persistently. The OTP password must be known and enabled or this example will not work. A lab power supply is needed. A SAID is needed whose OTP can be modified - this can not be undone.

Module architecture

This library contains 4 modules, see figure below (arrows indicate #include).

• aoosp_crc (aoosp_crc.cpp and aoosp_crc.h) is a small module that implements one function. It computes the OSP CRC checksum of a byte array. The module is stateless.

• aoosp_prt (aoosp_prt.cpp and aoosp_prt.h) is a slightly bigger module that implements several functions to pretty print telegrams. It is normally not used in production code. It is extensively used by the logging feature of module aoosp_send.

• aoosp_send (aoosp_send.cpp and aoosp_send.h) is the core module of the library. It contains functions that send commands and receive the responses if there is any. The module supports both RGBi's and SAIDs. Not all telegrams are implemented yet. The module is stateless, with one exception: it records if logging is enabled or disabled.

• aoosp_exec (aoosp_exec.cpp and aoosp_exec.h) is contains higher level features, which typically send multiple telegrams. A very prominent example is aoosp_exec_resetinit() which sends a RESET and INIT telegram, but auto detects if BiDir (terminator) or Loop (cable) is configured. Other high level functions help in accesses I2C devices connected to the SAID, or the OTP memory inside the SAID. Also stateless.

Each module has its own header file, but the library has an overarching header aoosp.h, which includes the module headers. It is suggested that users just include the overarching header.

API

The header aoosp.h contains the API of this library. It includes the module headers aoosp_crc.h, aoosp_prt.h, aoosp_send.h and aoosp_exec.h. The headers contain little documentation; for that see the module source files.

aoosp

• aoosp_init() not really needed (aoosp has no state to init), but added for forward compatibility.
• AOOSP_VERSION identifies the version of the library.

The module also implements the rarely used store for the SAID password to enter test mode, see aoosp_said_testpw_get() and aoosp_said_testpw_set(...).

aoosp_crc

• aoosp_crc(...) the only function implemented in this modules; computes the CRC of a byte array.

aoosp_prt

Contains several functions to print telegram fields more user friendly. Examples are:

• aoosp_prt_temp_said(...) to convert a SAID raw temperature to Celsius.
• aoosp_prt_stat_state(...) to convert a node stat to a string describing the power state.
• aoosp_prt_bytes(...) to convert a byte array (like a telegram) to a string.
• ...

These functions are publicly accessible, but are intended for logging in this library.

Warning: pretty print functions that return a char * all use the same global character buffer for returning the string. This means that only one such function can be used at a time. For example this will not work:

  printf("%s-%s", aoosp_prt_stat_rgbi(x), aoosp_prt_stat_said(x) ); // ERROR: double prt

aoosp_send

This is the core of the library. In principle it contains one function per telegram type. Examples are

• aoosp_send_reset(addr) resets all nodes in the chain (all "off"; they also lose their address).
• aoosp_send_initloop(addr,...) assigns an address to each node; also configures all nodes for Loop.
• aoosp_send_clrerror(addr) clears the error flags of the addressed node.
• aoosp_send_goactive(addr) switches the power state of the addressed node to active ("on").
• aoosp_send_setpwmchn(addr,...) configures the PWM settings of one channel of the addressed node ("lit").
• ...

It should be noted that some telegrams come in variants like setpwm and setpwmchn. The ...chn variant is for nodes with multiple RGB channels, like SAID, the other variant is for nodes with one channel, like RGBI.

There are several macros to help composing telegrams or analyzing responses.

• AOOSP_ADDR_XXX to pass (AOOSP_ADDR_BROADCAST, AOOSP_ADDR_GROUP5) or check (AOOSP_ADDR_ISUNICAST) addresses.
• To analyze identity, e.g. AOOSP_IDENTIFY_IS_SAID.
• To analyze various status bytes, e.g. AOOSP_STAT_FLAGS_OV, AOOSP_COMST_SIO1_MCU, AOOSP_SETUP_FLAGS_UV.
• To configure current drivers, e.g. AOOSP_CURCHN_FLAGS_DITHER, or AOOSP_CURCHN_FLAGS_SYNCEN.
• To configure/test I2C, e.g. AOOSP_I2CCFG_SPEED_400kHz, or AOOSP_I2CCFG_FLAGS_NACK.

This module supports logging. Via aoosp_loglevel_set(level) and aoosp_loglevel_get() the log level can be managed:

• aoosp_loglevel_none nothing is logged (default).
• aoosp_loglevel_args logging of sent and received telegram arguments.
• aoosp_loglevel_tele also logs raw (sent and received) telegram bytes.

aoosp_exec

Some operations on OSP nodes require multiple telegrams. Some frequent ones have been abstracted in this module.

• aoosp_exec_resetinit() sends RESET and INIT telegrams, auto detecting BiDir or Loop.
• aoosp_exec_resetinit_last() returns the address of the last node as determined by the last call to aoosp_exec_resetinit().
• aoosp_exec_otpdump(...) reads the entire OTP (mirror) and prints details requested in flags.
• aoosp_exec_setotp(...) updates one byte in the OTP (mirror).
• aoosp_exec_i2cenable_get(...) reads the I2C_BRIDGE_EN bit in OTP (mirror).
• aoosp_exec_i2cenable_set(...) writes the I2C_BRIDGE_EN bit in OTP (mirror).
• aoosp_exec_i2cpower(...) checks if the SAID has an I2C bridge, if so, powers the I2C bus.
• aoosp_exec_syncpinenable_get(...) reads the SYNC_PIN_EN bit from OTP (mirror).
• aoosp_exec_syncpinenable_set(...) writes the SYNC_PIN_EN bit to OTP (mirror).
• aoosp_exec_i2cwrite8(...) writes to an I2C device connected to a SAID with I2C bridge.
• aoosp_exec_i2cread8(...) reads from an I2C device connected to a SAID with I2C bridge.

Version history aoosp

• 2025 September 17, 0.9.0

  • Improved documentation for aoosp_adcled.ino, aoosp_adcpot.ino, aoosp_cluster.ino, aoosp_sync.ino, and aoosp_otp.ino.
  • aoosp_exec_otpdump() now dumps fields in table format (when passing AOOSP_OTPDUMP_CUSTOMER_FIELDS); old format retained via AOOSP_OTPDUMP_CUSTOMER_FIELDSLIST; updated examples and doc.
  • aoosp_exec_otpdump() now includes the EVK fields (at address 0x1F).
  • Added aoosp_exec_skipchns_get() and aoosp_exec_skipchns_set().
  • Added example aoosp_i2c12.ino (12 bits I2C).
  • Added support for 12 bit I2C: aoosp_send_i2cread12(), aoosp_send_i2cwrite12(), and macros aoosp_exec_i2cread12(), aoosp_exec_i2cwrite12().
  • Improved comments in aoosp_send.cpp/h.
  • Added link to examples.

• 2025 May 21, 0.8.0

  • Added examples aoosp_adcled.ino and aoosp_adcpot.ino.
  • Added aoosp_send_setadc(), aoosp_send_readadc() and aoosp_send_readadcdat().
  • Added ADC conversion aoosp_prt_adc() and aoosp_prt_adcmux().
  • All char * aoosp_prt_xxx() are now const char * aoosp_prt_xxx().
  • Fixed bug: aoosp_prt_bytes() printed old content when size was 0.
  • Fixed warning in aoosp_otpburn.ino.
  • Fixed: example aoosp_cur.ino mixed up AOOSP_CURCHN_FLAGS_DEFAULT and AOOSP_CURCHN_CUR_DEFAULT.
  • Improved API doc.
  • Changed examples to use max PWM.
  • Documentation (of examples) extended with new RGB names on OSP32 V11 ("L2.1 aka IN1").
  • Improved explanation of aoosp_sync.
  • Added link towards training slides in aoosp_otpburn.ino.

• 2025 March 3, 0.7.0

  • WARNING: AI constants AOOSP_I2CCFG_SPEED_XXX have been renamed to match new formula.
  • I2C speeds now conform datasheet (formula in aoosp_prt_i2ccfg_speed(), aoosp_send.h, introduced, AOOSP_I2CCFG_SPEED_MIN and AOOSP_I2CCFG_SPEED_MAX).

• 2025 February 21, 0.6.0

  • Corrected documentation for aoosp_said_testpw_get().
  • Added aoosp_send_aread(), aoosp_send_load() and aoosp_send_gload(), extended API doc on OTP management.
  • Corrected mapping to degrees C in aoosp_prt_temp_said().
  • Added aoosp_otpburn.ino.
  • Explained delay in aoosp_ledst.ino.
  • API documentation improvements, e.g. "(system) status", temperature conversion, i2c count.

• 2024 November 29, 0.5.0

  • Added example aoosp_ledst.ino.
  • aoosp_exec_setotp() now uses new aoosp_send_settestpw_sr().
  • Added telegram aoosp_send_settestpw_sr().
  • Explicit errors in aoosp_otp.ino.
  • Added telegrams aoosp_send_readledst() and aoosp_send_readledstchn().
  • Added aoosp_prt_ledst(); all aoosp_prt now use "-" as field separator.
  • Added telegram aoosp_send_godeepsleep().
  • Added example aoosp_tinfo explaining serial cast (with ASKTINFO).
  • Added telegrams aoosp_con_asktinfo() and variant aoosp_con_asktinfo_init().
  • Added API documentation for aoosp_loglevel_set() and aoosp_loglevel_get().
  • Removed old datasheet names for telegrams (in aoosp_send.cpp).

• 2024 October 24, 0.4.5

  • Added example aoosp_cluster.ino.
  • Documented (telegram) macros in readme.
  • SAID test password now in a store aoosp_said_testpw_get() and aoosp_said_testpw_set().
  • OTP write aoosp_exec_setotp() uses that store.

• 2024 October 22, 0.4.4

  • Response telegrams now checked for mismatch between payload size and PSI.

• 2024 October 8, 0.4.3

  • Prefixed modules.drawio.png with library short name.
  • Documentation update in: readme.md, aoosp_exec.cpp, aoosp_prt.cpp, and aoosp_send.cpp.
  • Added example aoosp_cur.ino (drive current demo).
  • Fixed white lines in aoosp_exec.h.
  • Log of aoosp_send_initxxx() now prints 3 digits.
  • Moved domain from github.com/ams-OSRAM-Group to github.com/ams-OSRAM.

• 2024 September 10, 0.4.2

  • Fixed TID bug in aoosp_con_seti2ccfg().
  • aoosp_exec_i2cpower(addr) now also checks if addr is a SAID.
  • Detailed addressing for aoosp_send_xxx() and removed old datasheet names.
  • Corrected documentation on addr in aoosp_exec_xxx() functions.
  • Added topology check to aoosp-time.ino.
  • Added explanation for SYNC via pin in aoosp_sync.ino.
  • Added remark on OTP password for aoosp_otp.ino.
  • I2C in aoop_i2c.ino description updated and device address changed to match OSP32.
  • Now also powering I2C bus in aoosp_i2c.ino for EEPROM.
  • Role of 'mult' in aoosp_error.ino explained.
  • Added BEHAVIOR section to explanation in examples.

• 2024 September 5, 0.4.1

  • API section in readme now shows parameter names.
  • Added aoosp_exec_resetinit_last().
  • Made output parameters of aoosp_exec_resetinit() optional (adapted an example).
  • Bug fix: when aoosp_exec_resetinit had NULL for output parameters they were still assigned.
  • Bug fix: changed AOOSP_ADDR_NOTNIT to AOOSP_ADDR_UNINIT in AOOSP_ADDR_GROUP.

• 2024 August 28, 0.4.0

  • Renamed/split AOOSP_ADDR_MIN|MAX to AOOSP_ADDR_UNICASTMIN|MAX and AOOSP_ADDR_GLOBALMIN|MAX.
  • Added AOOSP_OTPADDR_CUSTOMER_MIN|MAX.
  • Added links in readme.md for all example sketches.

• 2024 August 9, 0.3.1

  • Typos fixed in aoosp_send.cpp.
  • In aoosp_send.h cleaned up AOOSP_ADDR_xxx.
  • Typos fixed in readme.md, aoosp.cpp, aoosp_crc.cpp, aoosp_exec.h.
  • Typos fixed in aoosp_i2c.ino, aoosp_sync.ino, aoosp_topo.ino.
  • Typos fixed in aoosp_exec.cpp.

• 2024 August 5, 0.3.0

  • In aoosp_send.h all non-implemented TIDs tagged as not-yet-implemented or reserved.
  • Corrected link to GitHub from aotop to OSP_aotop.
  • Remove "oalib" from sentence= in library.properties.
  • Added #include "../../said-password.h".
  • Added aoosp_exec_syncpinenable_get() and aoosp_exec_syncpinenable_set() and hw sync in aoosp_sync.ino.
  • Arduino name changed from OSP Telegrams - aoosp to OSP Telegrams aoosp.
  • Renamed dir extra to extras.
  • license.txt, examples\xxx.ino line endings changed from LF to CR+LF.
  • Fixed argument test in aoosp_con_setcurchn().

• 2024 July 02, 0.2.4

  • Initial release candidate.

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