# IOT-003 source register

Evidence cutoff and access date for every entry: **2026-10-17**. Issuers are the manufacturers. These are scoped documentation reads for a theoretical overview, not hardware tests or purchasing checks. No source identifies any particular product design.

| ID | Primary source / edition | Relevant material read | Claims and limits |
|---|---|---|---|
| S01 | [TI CC2640R2F datasheet](https://www.ti.com/lit/ds/symlink/cc2640r2f.pdf), SWRS204C, revised September 2020 | Features, description, functional block diagram; conceptual subsystem identities only | C01; chip resources and package-dependent I/O. Does not establish application headroom, board consumption or final RF behavior |
| S02 | [TI LAUNCHXL-CC2640R2](https://www.ti.com/tool/LAUNCHXL-CC2640R2), live product documentation, publication date unspecified | Board identity and linked SDK | C02; evaluation-board identity only, no assumed hardware revision |
| S03 | [TI SDK download](https://www.ti.com/tool/download/SIMPLELINK-CC2640R2-SDK) and [release notes](https://software-dl.ti.com/simplelink/esd/simplelink_cc2640r2_sdk/5.30.01.11/exports/release_notes_simplelink_cc2640r2_sdk_5_30_01_11.html), 5.30.01.11, 2024-09-03 | Introduction and device/development-board support sections | C03; documentation baseline, no installation/build/feature or security validation |
| S04 | [Arduino UNO R4 WiFi manual](https://docs.arduino.cc/resources/datasheets/ABX00087-datasheet.pdf), ABX00087, displayed modified 2026-10-15 | Main MCU, connectivity module, features, power and pin voltage; §§5–6, 11 | C04; distinct processors and external CAN transceiver requirement. No electrical interchangeability or complete peripheral claims |
| S05 | [Espressif ESP32-DevKitC V4 guide](https://docs.espressif.com/projects/esp-idf/en/v4.4/esp32/hw-reference/esp32/get-started-devkitc.html), ESP-IDF documentation v4.4, publication date unspecified | Board variants, functional description and pin restrictions | C05; versioned board-description reference, not a recommendation to use this SDK release. Current documentation route also checked, but produced little extractable body text |
| S06 | [Nordic nRF52840 DK documentation](https://www.nordicsemi.com/Products/Development-hardware/nRF52840-DK/Download), live page, publication date unspecified | Kit description, protocol scope, hardware revisions | C06; protocol-development categories only. No concurrency or exact SDK-support promise; hardware files list 3.0.3 but no physical kit was inspected |
| S07 | [ST NUCLEO-F446RE](https://www.st.com/en/evaluation-tools/nucleo-f446re.html), live page, publication date unspecified | Product identity, description, connectivity and integrated ST-LINK | C07; STM32F446RE platform and programming/debug facilities. Shared family feature list is not attributed wholesale to this board |
| S08 | [Raspberry Pi 5](https://www.raspberrypi.com/products/raspberry-pi-5/), live product documentation, publication date unspecified | SBC identity and platform overview | C08; gateway category example, no benchmark, thermal or deadline claim |
| S09 | [Raspberry Pi Compute Module hardware](https://www.raspberrypi.com/documentation/computers/compute-module.html), live documentation, publication date unspecified | CM5 identity, carrier/IO-board responsibilities, boot and OS context | C09; integration division, no assembly qualification or assumed variant |
| S10 | [Arduino Portenta Machine Control manual](https://docs.arduino.cc/resources/datasheets/AKX00032-datasheet.pdf), AKX00032, displayed modified 2026-10-15 | Features, power and channel types | C10; supply and field-interface examples. Isolation must be examined by domain/channel; no blanket isolation claim |
| S11 | [Arduino Opta collective datasheet](https://docs.arduino.cc/resources/datasheets/AFX00001-AFX00002-AFX00003-datasheet.pdf), AFX00001/2/3, displayed modified 2026-10-15 | §§3–5, interfaces, input/output and product view | C11; micro-PLC product category and terminal/relay structure. Variant capabilities and load limits need exact selection; no safety claim |

## Sources added for v1.1

Access date for these records: 2026-10-17. Scope is exact documented features and conceptual execution, not target execution.

| ID | Primary source / edition | Relevant material read | Claims and limits |
|---|---|---|---|
| S12 | [TI technical reference manual](https://www.ti.com/lit/ug/swcu117i/swcu117i.pdf), SWCU117I, June 2020 | Main/system architecture, power management, AUX/Sensor Controller chapter 17 and toolchain interface | C18/C20; family architecture applied only where exact-part S01 confirms applicability |
| S13 | [TI software architecture](https://software-dl.ti.com/simplelink/esd/simplelink_cc2640r2_sdk/5.30.01.11/exports/docs/ble5stack/ble_user_guide/html/ble-stack-5.x-guide/software_architecture.html), SDK 5.30.01.11 / BLE5-Stack guide 1.01.15.00 | Single-device/network-processor configurations, C interface, task ownership, link configuration | C17/C18; conceptual workflow. Opening Cortex-M4F description conflicts with exact-part S01; use Cortex-M3 from S01 instead |
| S14 | [TI GAP guide](https://software-dl.ti.com/simplelink/esd/simplelink_cc2640r2_sdk/5.30.01.11/exports/docs/ble5stack/ble_user_guide/html/ble-stack-5.x/gap-cc2640.html), same SDK/guide | Roles, discovery/advertising and connection states | C19; conceptual connected example, not a reproduced sample project |
| S15 | [TI GATT guide](https://software-dl.ti.com/simplelink/esd/simplelink_cc2640r2_sdk/5.30.01.11/exports/docs/ble5stack/ble_user_guide/html/ble-stack-5.x/gatt.html), same SDK/guide | Services/characteristics, independent roles, notification subscription/client configuration | C19; application consumption and historical transfer require their own policy |
| S16 | [SDK documentation overview](https://software-dl.ti.com/simplelink/esd/simplelink_cc2640r2_sdk/5.30.01.11/exports/docs/Documentation_Overview.html), 5.30.01.11 | Distinct BLE-Stack/BLE5-Stack components, drivers and RTOS routes | C20; no mixing of stack footprint/features or actual compiler compatibility claim |
| S17 | [Nordic nRF52840 product specification overview](https://www.nordicsemi.com/products/nrf52840), live page, publication date unspecified | CPU, flash/RAM, radio/protocol and peripheral feature list | C21; silicon totals only, not available application space or measured energy |
| S18 | [ESP32-S3 datasheet](https://documentation.espressif.com/esp32_s3_datasheet_en.pdf), v2.2 | CPU, SRAM and wireless features | C22; exact S3 silicon, not all ESP32 devices |
| S19 | [ESP32-S3-DevKitC-1 guide](https://documentation.espressif.com/esp-dev-kits/en/latest/esp32s3/esp32-s3-devkitc-1/user_guide_v1.1.html), board guide v1.1 | N8R8 variant/module flash and PSRAM table; board facilities | C22; N8R8, not a generic unpinned S3 board or ESP32-DevKitC V4 |
| S20 | [ESP-IDF external RAM](https://docs.espressif.com/projects/esp-idf/en/v5.4.2/esp32s3/api-guides/external-ram.html), v5.4.2 | External allocation integration and restrictions | C22; explains why external PSRAM is not interchangeable with all internal SRAM; no selected firmware build |
| S21 | [Pico-series documentation](https://www.raspberrypi.com/documentation/microcontrollers/pico-series.html), live docs, publication date unspecified | Pico 2 W RP2350, CPU alternatives, RAM, board flash, PIO and wireless | C23; MCU board, Arm/RISC-V alternatives not four cores in parallel |
| S22 | [STM32F446RE](https://www.st.com/en/microcontrollers-microprocessors/stm32f446re.html) and [datasheet](https://www.st.com/resource/en/datasheet/stm32f446re.pdf), exact part / DS10693 | 180 MHz CPU, 512 KB flash, 128 KB main SRAM, timers/ADC/DMA | C23; selected part resources, not generic STM32 capabilities; separate backup SRAM not counted in main RAM |
| S23 | [Siemens IOT2050 operating instructions](https://cache.industry.siemens.com/dl/files/016/109779016/att_1018122/v2/iot2050_operating_instructions_en_en-US.pdf), A5E39456816-AE, 04/2023 | Scope/variants, gateway role, serial/Ethernet interfaces, supply §§1, 9–10 | C24; historical model-specific manual read alongside current gateway product page; no claim it covers every current revision |
| S24 | [Siemens IOT2050 product page](https://www.siemens.com/en-gb/products/simatic-iot-gateways/iot2050/), live page | Gateway/integration role | C24; no factory control/safety or runtime timing qualification |
| S25 | [Bluetooth Core Specification](https://www.bluetooth.com/specifications/specs/), version not pinned in this revision | Connection interval range (7.5 ms to 4 s), default ATT MTU of 23 bytes, little-endian attribute values, CCCD (0x2902) | C28, C30; general protocol facts, not TI-specific behavior; exact clause numbers to be added at the next source read |
| S26 | [RFC 7228](https://www.rfc-editor.org/info/rfc7228/), May 2014 | Table 1 constrained-node classes (Class 1 about 10 KiB RAM / 100 KiB code; Class 2 about 50 KiB / 250 KiB) | C27; informational classification, re-read 2026-10-17 |

## Status, errata and freshness limits

The TI product catalog lists datasheet Rev. C and device errata Rev. A (2019-12-03). The errata body could not be retrieved through the research browser. Its contents are **not** used as evidence. No absence-of-errata assertion is made. A target-specific design must read the actual errata and applicable SDK security notices before relying on peripheral/radio behavior.

Other board pages and manuals were checked for the narrow overview claims, not exhaustively audited for every erratum, security advisory or product certification. Exact physical revisions were not inspected. Volatile distributor stock, pricing, current SDK suitability, supply commitments and safety/compliance conclusions are excluded. The chapter does not recommend ordering a specific board.

S01–S24 are source identifiers, not confidence scores. Tables in the chapter contain engineering interpretations beside narrowly sourced product features. C12–C26 record those distinctions. The software guide CPU conflict is recorded under S13; exact-part silicon identity takes precedence. No vendor text or diagrams are reproduced.

## Focused editorial recheck — 2026-10-19

The [pinned TI BLE5-Stack 1.01.15.00 GATT guide](https://software-dl.ti.com/simplelink/esd/simplelink_cc2640r2_sdk/5.30.01.11/exports/docs/ble5stack/ble_user_guide/html/ble-stack-5.x/gatt.html) was read for notification configuration and the default 23-byte ATT MTU with a 20-byte notification value. This narrows the current source register’s S13/S25 claims; it is not a new SDK, radio or board qualification. The acquisition-time explanation now distinguishes sampling semantics from conversion/result availability and queue time; it does not prescribe a new device timing API. No broad manufacturer-document refresh was performed for this style revision. Earlier errata, exact-clause and vendor-PDF verification limits remain open.

## Claim recheck for C34 to C36 — 2026-10-26

- **S19, ESP32-S3-DevKitC-1 user guide v1.1** ([link](https://documentation.espressif.com/esp-dev-kits/en/latest/esp32s3/esp32-s3-devkitc-1/user_guide_v1.1.html)) was fetched and read on 2026-10-26. It states that GPIO35, GPIO36 and GPIO37 are used for communication between the ESP32-S3 and the SPI flash/PSRAM and are not available for external use on boards with embedded octal flash/PSRAM modules. C36 is confirmed for the N8R8 variant; no chapter text changed.
- **S25, Bluetooth Core Specification:** the specs page ([link](https://www.bluetooth.com/specifications/specs/)) was fetched, but it lists only version pages (6.3 current) and the specification text was **not** read. C34 (CCCD persistence only for bonded clients, Vol 3 Part G) and C35 (supervision timeout above (1 + latency) x interval x 2, Vol 6 Part B) are corroborated only by secondary quotations in vendor and issue-tracker posts, which agree with the chapter wording. Those are not primary re-reads, so S25 stays "version not pinned; clause numbers to be added" and the chapter's `Sources checked` date is unchanged.