Actuation Module (AM) Design Specification

Status: In Review Project: Enigma-NG Author: Izzyonstage & GitHub Copilot Version: v.0.1.0 Associated Hardware Revision: Rev A Last Updated: 2026-05-22

1. Overview

The Actuation Module (AM) is a small shared service PCB used anywhere Enigma-NG needs one local servo-driven single-step actuation cycle without continuous CM5 supervision. The same AM is fitted:

• once on the Controller to actuate the main depression bar for virtual keypress injection
• once on each Extension to regenerate a group-boundary carry event into a local single-step actuation of the next 5-rotor group

The host board only provides power and a single active-low ACTUATE_REQUEST_N line. The AM owns the power-up homing sequence, request latching / one-shot behaviour, servo PWM generation, and local LED diagnostics.

2. Functional & Design Requirements

Functional Requirements

ID	Functional Requirement	Notes	Satisfied By / Cross-Ref
FR-AM-01	Accept a local power feed from a host board	Host provides 5V_MAIN, 3V3_ENIG, and multiple GND returns	§3 Connectivity; BOM J1
FR-AM-02	Accept a single active-low ACTUATE_REQUEST_N input from the host board	Same electrical contract works for a CM5-driven request on the Controller and a switch-derived request on an Extension	§3 Connectivity; BOM J1
FR-AM-03	Auto-home the local servo on power-up without host feedback wires	Host waits a fixed startup window; AM shows local LED state only	§4 Local control behaviour; BOM J3, D1-D3
FR-AM-04	Convert each valid request into exactly one complete servo cycle	Held request inputs must not retrigger until the current cycle completes and the input has released	§4 Local control behaviour; BOM U1
FR-AM-05	Drive one external hobby servo through a local loom connection	Servo is mechanically mounted near the actuation bar, not on the AM PCB	§3 Connectivity; BOM J2
FR-AM-06	Monitor a local home switch through a separate loom connection	Home switch is physically mounted near the mechanism and wired back to the AM	§3 Connectivity; BOM J3
FR-AM-07	Provide local diagnostic indication without any host-side status return pins	PWR, HOMED, and ACT LEDs are sufficient for bench and service diagnostics and shall remain visible from the AM board edge during maintenance	BOM D1-D3, R1-R3
FR-AM-08	Provide a dedicated local SWD programming / service header on the AM itself	Required so the STM32 can always be programmed and debugged before first use without depending on the host board	§3.4; BOM J4
FR-AM-09	Provide a dedicated local UART bootloader / service header on the AM itself	Keep a second programming path available for ad-hoc USB-to-UART use, with explicit boot-entry control exposed on the header pinout	§3.5; BOM J5
FR-AM-10	Provide a local momentary reset control next to the UART service header	Required so the UART bootloader path can be entered without awkward clip leads on RESET_N	§3.6; BOM SW1
FR-AM-11	Provide a local momentary BOOT0 control next to the UART service header	Required so the UART bootloader path can be entered directly at the AM without needing a temporary jumper on the header	§3.7; BOM SW2

Design Requirements

ID	Design Requirement	Specification	Satisfied By / Cross-Ref
DR-AM-01	PCB stackup	Inverted stackup per design/Standards/Global_Routing_Spec.md §2.3.2	Board_Layout.md
DR-AM-02	Host dock connector	J1 = Hirose DF40C-20DP-0.4V(51) (module-side 20-pin plug, 0.4mm pitch); host uses matching DF40HC(3.5)-20DS-0.4V(51) receptacle; stacking height = 3.5mm; carries 5V_MAIN, 3V3_ENIG, ACTUATE_REQUEST_N, and GND on a single connector	§3.1; BOM J1; design/Standards/Global_Routing_Spec.md §7.1
DR-AM-03	AM mounting holes	MH1-MH4 shall be M2.5mm NPTH through-holes with copper annular ring using the KiCAD built-in MountingHole_Pad footprint (no purchasable BOM component); pads shall be connected to GND. Matching 3.5mm SMT standoffs (9774035151R) on the host board (EXT MH5-MH8 or CTL MH5-MH8). Placement shall follow the asymmetric pattern: MH1 (top-left) and MH3 (bottom-left) at 7 mm from the left edge and 7 mm from the top and bottom edges respectively; MH2 (top-right) and MH4 (bottom-right) at 7 mm from the right edge and 12 mm from the top and bottom edges respectively. This non-square pattern enforces a single valid mating orientation, compensating for the polarity-free DF40 connector body. Exact coordinates to be confirmed at PCB layout stage. Per DEC-057 daughterboard exception — AM mounts to CTL/EXT via M2.5 standoffs and uses GND (not GND_CHASSIS).	Board_Layout.md; §3.1
DR-AM-04	Servo loom header	J2 = Adam Tech PH1-05-UA, manually fitted post-PCBA; only pins 1-3 are active in Rev A	§3.2; BOM J2
DR-AM-05	Home-switch loom header	J3 = Adam Tech PH1-05-UA, manually fitted post-PCBA; twisted-pair wiring required for the active signal and return	§3.3; BOM J3
DR-AM-06	Local controller architecture	U1 shall be a small 3.3V local controller with native hardware PWM, at least 2 digital inputs, at least 4 spare / LED-capable GPIOs, power-on reset, and a package suitable for low-profile service-module assembly	§4; BOM U1
DR-AM-07	Diagnostics LED parts and placement	Reuse the existing green 0603 status LED and 330Ω 0402 resistor already used on Encoder boards, but place the LED footprints at the visible board edge on the PCBA side so their light remains observable when the AM is installed upside-down	BOM D1-D3, R1-R3; Board_Layout.md
DR-AM-08	Home-input biasing	ACTUATION_HOME_N uses a local 10kΩ pull-up to 3V3_ENIG plus a 1µF local RC debounce capacitor - RC time constant 10 ms	BOM R4, C1
DR-AM-09	Mounting orientation and layer assignment	Module mounts upside-down on host board using intentionally inverted 4-layer assignment per design/Standards/Global_Routing_Spec.md §2.3.2 and DEC-016; L1 (component/connector-facing side) faces host PCB, L4 (exterior face) is user-visible side	Board_Layout.md; DEC-016
DR-AM-10	SWD service connector	J4 = Adam Tech PH1-05-UA, manually fitted 1x5 2.54mm SWD header using the common compact 5-pin STM32/ST-LINK flying-lead order (VTref, SWCLK, GND, SWDIO, RESET_N)	§3.4; BOM J4
DR-AM-11	Inter-board component envelope	All PCBA-fitted parts on the enclosed connector-facing side of the AM shall remain low profile and shall not exceed 2.0 mm installed height above the PCB; all manual-fit loom / service headers remain on the opposite side	Board_Layout.md; §4
DR-AM-12	UART bootloader connector	J5 = Adam Tech PH1-05-UA, manually fitted 1x5 2.54mm UART bootloader header; pins 1-4 shall follow the common 3.3V TTL serial order (GND, 3V3, TX, RX) and pin 5 shall expose BOOT0	§3.5; BOM J5
DR-AM-13	Local reset button	SW1 = Omron B3F-1070 or equivalent SPST NO through-hole tactile switch, wired to pull RESET_N low momentarily and placed adjacent to J5 for convenient UART bootloader entry	§3.6; BOM SW1
DR-AM-14	Local BOOT0 button	SW2 = Omron B3F-1070 or equivalent SPST NO through-hole tactile switch, wired to assert BOOT0 HIGH while pressed and placed adjacent to J5 / SW1 for convenient UART bootloader entry	§3.7; BOM SW2
DR-AM-15	Local decoupling and reservoir caps	AM is exempt from the full 5x bulk-entry-bank rule used on larger boards, but it shall still include local STM32 supply decoupling plus compact 3V3/5V reservoir caps: C2-C3 = 100nF X7R 0402 at the STM32 VDD/VDDA supply domain (pin 4, combined VDD/VDDA in LQFP-32), C7 = 100nF X7R 0402 also at STM32 VDD/VDDA (pin 4, combined VDD/VDDA in LQFP-32; multiple caps per datasheet decoupling guidance), C4 = 4.7uF X7R on 3V3_ENIG, C5 = 10uF X7R on 5V_MAIN near the servo/power entry region. Per GRS §3.2 per-IC bypass capacitor requirement.	§4; BOM C2-C3, C5, C7; Board_Layout.md
DR-AM-16	RESET_N filter capacitor	An external 100 nF X7R filter capacitor (C6) shall be placed between the MCU NRST pin and GND per STM32G071 datasheet Figure 23 to suppress voltage spikes on the reset line	§3.6; BOM C6; Board_Layout.md
DR-AM-17	BOOT0 series protection resistor	A 10 kΩ series resistor (R5) shall be placed between the SW2 / J5 pin 5 shared node and the MCU BOOT0 pin to limit current during BOOT0 assertion and protect the pin from conflict when the external harness and SW2 are both driven. STM32G071 BOOT0 shares the PA14/JTCK-SWCLK pin after first reset; the STM32G071 activates an internal pull-down on PA14 upon reset (datasheet footnote 6), guaranteeing BOOT0 idles LOW when SW2 is open — no external pull-down is required. Per DEC-047.	§3.7; BOM R5; Board_Layout.md
DR-AM-18	ACTUATE_REQUEST_N pull-up policy	The ACTUATE_REQUEST_N signal on J1 pin 15 shall be held HIGH by the STM32G071K8T3TR internal GPIO pull-up (PUPDR = 0b01) only; no external pull-up resistor shall be fitted on the AM hardware	§3.1 J1 pin 15; BOM (no external pull-up component)
DR-AM-19	STM32G071K8T3TR LQFP-32 supply topology	The LQFP-32 package has a single combined VDD/VDDA pin (pin 4); all decoupling caps C2, C3, and C7 shall target pin 4 exclusively; no separate VDDA pin exists in this package	§4; BOM C2-C3, C7

Note - Minimum board size guidance (non-binding): The DR-AM-03 asymmetric mounting hole pattern implies a minimum board height of approximately 26 mm (right-pair 12 mm insets x 2 plus 1 mm edge clearance each side) and a minimum board width of approximately 28 mm (7 mm insets each side plus clearance for the DF40C connector body). These are guidance values only; final dimensions shall be determined during schematic capture and PCB layout.

Component Block Diagram

flowchart TD
  subgraph host["Host Interface"]
    J1["J1 DF40C-20<br>5V_MAIN · 3V3_ENIG · ACTUATE_REQUEST_N"]
  end

  subgraph mcu["MCU"]
    U1["U1 STM32G071K8T3TR LQFP-32"]
  end

  subgraph actuator["Actuator Interface"]
    J2["J2 Servo Loom PH1-05-UA"]
    J3["J3 Home Switch PH1-05-UA"]
  end

  subgraph debug["Service / Debug"]
    J4["J4 SWD Header<br>SWCLK · SWDIO · RESET_N · VTref"]
    J5["J5 UART / BOOT0<br>GND · 3V3 · TX · RX · BOOT0"]
    SW1["SW1 RESET_N B3F-1070"]
    SW2["SW2 BOOT0 B3F-1070"]
  end

  subgraph leds["Indicators"]
    D1["D1 PWR green 0603"]
    D2["D2 HOMED green 0603"]
    D3["D3 ACT green 0603"]
  end

  J1 --> U1
  U1 --> J2
  J3 --> U1
  J4 --> U1
  J5 --> U1
  SW1 --> U1
  SW2 --> U1
  U1 --> D1
  U1 --> D2
  U1 --> D3

3. Connectivity

3.1 J1 - Host Dock (Power + Trigger)

Module-side part: Hirose DF40C-20DP-0.4V(51) (plug, 20-pin, 0.4mm pitch, ~1.14mm above PCB)
Host-side mating part: Hirose DF40HC(3.5)-20DS-0.4V(51) (receptacle, 20-pin, 3.5mm stacking height)
Board-to-board gap: 3.5mm (clearance to DR-AM-11 2.0mm limit: 1.5mm ✔)

⚠️ Polarity note: The DF40 connector body is mechanically polarity-free (Hirose Note 4). Correct mating orientation is enforced by the asymmetric standoff hole pattern (MH1-MH4; see DR-AM-03 and Board_Layout.md). Pin 1 is defined as the top-left pin when the AM is viewed from its component side (connector-facing side) with the short standoff-pair edge on the left. Verify against the silkscreen pin-1 marker on both AM and host board before installation (per design/Standards/Global_Routing_Spec.md §7.1).

Current budget: Rated 0.3 A per contact.
5V_MAIN: 5 pins x 0.3 A = 1.5 A available (≥ 3x SG90 stall current headroom ✔).
3V3_ENIG: 2 pins x 0.3 A = 0.6 A available.
ACTUATE_REQUEST_N: logic signal only (< 5 mA).

ACTUATE_REQUEST_N is active-low. The host asserts a request by pulling the line LOW. The idle-HIGH bias is provided by the STM32 internal GPIO pull-up (PUPDR = 0b01) configured in firmware - no external pull-up resistor is fitted on the AM hardware.

Pin	Signal	Direction	Notes
1	5V_MAIN	Host → AM	Servo supply
2	GND	-	Servo power return
3	5V_MAIN	Host → AM	Servo supply
4	GND	-	Servo power return
5	5V_MAIN	Host → AM	Servo supply
6	GND	-	Servo power return
7	5V_MAIN	Host → AM	Servo supply
8	GND	-	Servo power return
9	5V_MAIN	Host → AM	Servo supply
10	GND	-	Servo power return
11	3V3_ENIG	Host → AM	Logic rail
12	GND	-	Logic return
13	3V3_ENIG	Host → AM	Logic rail
14	GND	-	Logic return
15	ACTUATE_REQUEST_N	Host → AM	Active-low request input
16	GND	-	Signal return / guard
17	GND	-	Signal return / guard
18	GND	-	Signal return / guard
19	GND	-	Signal return / guard
20	GND	-	Signal return / guard

3.2 J2 - Servo Loom Header

Part: Adam Tech PH1-05-UA - 1x5 2.54mm male pin header, manually fitted after PCB assembly.

Pin	Signal	Notes
1	5V_MAIN	Servo supply
2	GND	Servo return
3	SERVO_PWM	AM-generated local PWM
4	NC	Reserved
5	NC	Reserved

3.3 J3 - Home Switch Loom Header

Part: Adam Tech PH1-05-UA - 1x5 2.54mm male pin header, manually fitted after PCB assembly.

Pin	Signal	Notes
1	ACTUATION_HOME_N	Active-low home-switch input
2	GND	Twisted-pair return with pin 1
3	GND	Spare return
4	NC	Reserved
5	NC	Reserved

3.4 J4 - SWD Programming / Service Header

Part: Adam Tech PH1-05-UA - 1x5 2.54mm male pin header, manually fitted for firmware loading and bench-service access.

This is the primary programming and debug header for the selected STM32. It uses the common compact 5-pin SWD flying-lead order so an ST-LINK, J-Link, or similar SWD probe can be adapted without inventing a board-specific pin order.

Pin	Signal	Notes
1	3V3_ENIG	Target reference / programming rail
2	SWCLK	SWD clock
3	GND	Reference
4	SWDIO	SWD data I/O
5	RESET_N	Target reset

3.5 J5 - UART Bootloader / Service Header

Part: Adam Tech PH1-05-UA - 1x5 2.54mm male pin header, manually fitted for bench-service UART access and optional STM32 ROM-bootloader programming.

Pins 1-4 keep the common 3.3V TTL serial order so a simple ad-hoc UART harness can be made easily. Pin 5 exposes BOOT0 so the ROM bootloader can still be selected from an external harness when needed. At the board itself, the AM also provides local tactile buttons for both RESET_N and BOOT0. In use, BOOT0 is treated as a momentary operator action with a timing constraint: hold it active while reset occurs, then release it after the boot-mode sample point. To make that practical on the bench, the AM provides a local reset button at SW1 and a local BOOT0 button at SW2.

Pin	Signal	Notes
1	GND	Reference
2	3V3_ENIG	Target reference / logic rail
3	UART_TX	AM -> external UART adapter
4	UART_RX	External UART adapter -> AM
5	BOOT0	Assert HIGH during reset to enter the STM32 ROM bootloader; connects to SW2 / J5 node, then to MCU BOOT0 pin via series R5 (10 kΩ)

3.6 SW1 - Local Reset Button

Part: Omron B3F-1070 - SPST NO through-hole tactile switch.

SW1 provides a local momentary reset by pulling RESET_N LOW while pressed. Place it next to J5 so the normal UART bootloader sequence is straightforward:

1. Hold BOOT0 HIGH on J5 pin 5.
2. Press and release SW1 to reset the STM32.
3. Release BOOT0 after reset if desired; the MCU will stay in the ROM bootloader until power is cycled or the next reset occurs with BOOT0 LOW.

RESET_N filter capacitor (C6): The RESET_N line carries a 100 nF X7R filter capacitor (C6) to GND, placed adjacent to U1's NRST pin per STM32G071 datasheet Figure 23 to suppress voltage spikes on the reset line. C6 uses the same approved part as C1-C3.

3.7 SW2 - Local BOOT0 Button

Part: Omron B3F-1070 - SPST NO through-hole tactile switch.

SW2 provides a local momentary BOOT0 assertion by driving BOOT0 HIGH while pressed. Place it beside SW1 so the two-button UART bootloader action is simple and repeatable:

1. Press and hold SW2.
2. Press and release SW1.
3. Release SW2.

BOOT0 series resistor (R5): SW2 and J5 pin 5 share a common node that connects to the MCU BOOT0 pin via series resistor R5 (10 kΩ). R5 limits current during BOOT0 assertion and prevents conflict if the external harness and SW2 are operated simultaneously. R5 uses the same approved part as R4. The STM32G071 internal pull-down on PA14 (datasheet footnote 6) guarantees BOOT0 idles LOW when SW2 is open; no external pull-down resistor is required.

This gives the same effect as holding BOOT0 HIGH on J5 pin 5 during reset, but without needing a temporary jumper or second hand on the header itself.

3.8 Device-to-Design Net Name Mapping

The following table maps STM32G071 device pin names to the board-level net names used in this document and in the KiCAD schematic:

Component Pin Name	Design Net Name	Notes
NRST	RESET_N	STM32 reset pin; active-low; board-local net (does not conflict with system-level CPLD_RESET_N)

4. Local Control Behaviour

The AM is intentionally host-light and mechanically local:

1. Firmware is loaded via J4 (SWD) or, when needed, via J5 plus the local SW1 / SW2 button pair before the module is placed into service.
2. On power-up, U1 boots from local non-volatile memory and performs a homing sequence using the external home switch on J3.
3. Until homing completes, further actuation requests are ignored.
4. Once homed, each valid low-going ACTUATE_REQUEST_N event is latched and converted into one complete servo cycle.
5. A held request input must not cause repeated cycles; the request must release before the next cycle can be accepted.
6. The host receives no BUSY, HOMED, or fault wire. Service state is indicated only by the local LEDs.

Local supply-decoupling note

The AM should follow a small daughterboard decoupling strategy, not the full bulk-entry-bank pattern used by larger mainline boards. The closest precedent is the JTAG Module (JM), which is explicitly exempt from the 5x bulk-entry-bank rule and instead uses per-IC 100nF decoupling plus a single 4.7uF entry filter.

The AM should follow the same general daughterboard logic, but with one important addition: unlike the JM, the AM drives a local servo load from 5V_MAIN, so it should include a local 5V reservoir cap as well as MCU decoupling. Rev A therefore requires:

• C2, C3, C7: 100nF X7R 0402 local decoupling at the STM32 VDD/VDDA supply domain (all three target pin 4 per DR-AM-15 and DR-AM-19)
• C4: 4.7uF X7R local 3V3_ENIG reservoir / entry filter
• C5: 10uF X7R local 5V_MAIN reservoir near the servo power path

This does not replace the host board's upstream bulk decoupling. It is local high-frequency decoupling and short-burst current support for the AM itself.

Preferred controller-part requirement

The selected U1 is STMicroelectronics STM32G071K8T3TR. This is a 32-pin 3.3V STM32G071 device with native timer/PWM resources and enough GPIO margin for the AM's homing input, request input, diagnostic LEDs, and service/programming access. A standalone PWM driver such as the PCA9685 remains a reviewed part in the repository, but it is not sufficient on its own for the AM because the module also needs autonomous homing, request latching, and cycle sequencing. The selected STM32 also keeps both requested service paths practical: J4 carries the normal SWD debug interface, while J5 plus the local SW1 / SW2 button pair exposes a simple UART/BOOT0 path for ROM-bootloader use with ad-hoc wiring. The reviewed STM32 family reference is design/Datasheets/stm32g071.md, which links back to the preserved vendor PDF at design/Datasheets/stm32g071.pdf.

Approved supplier references for the selected AM controller are:

• DigiKey: 497-STM32G071K8T3TR-ND
• Mouser: 511-STM32G071K8T3TR
• JLCPCB: global sourcing or consignment only

The Mouser product page is also useful during later PCB work because it provides footprint and 3D-model links for the selected package.

5. Software / Firmware Cross-Reference

The AM firmware specification now lives under the software tree at design/Software/Actuation_Module/Design_Spec.md.

That software document is the source of truth for:

• the SWD and UART boot / programming paths
• the SW1 / SW2 UART bootloader button sequence
• the STM32 firmware state machine
• homing, actuation, and fault behaviour
• firmware bring-up order and implementation notes

This hardware design spec remains the source of truth for the AM's electrical interface, connector pinouts, mechanical constraints, and BOM.

6. Bill of Materials

RefDes	Specification	MPN	Manufacturer	DigiKey PN	Mouser PN	JLCPCB PN	Alt Supplier + PN	Notes	Footprint Available	Footprint Downloaded	Qty
C1	1µF X7R 50V 0805	C0805C105K5RACTU	Kemet	399-C0805C105K5RACTUCT-ND	80-C0805C105K5R	C3018567	-	-	✔	✔	1
C2-C3, C6-C7	100nF X7R 50V 0402	CL05B104KB5NNNC	Samsung	1276-CL05B104KB5NNNCCT-ND	187-CL05B104KB5NNNC	C960916	-	-	✔	✔	4
C4	4.7µF X7R 50V 1210	CGA6P3X7R1H475K250AD	TDK	445-10040-1-ND	810-CGA6P3X7R1H475KD	C3877549	-	-	✔	✔	1
C5	10µF X7R 50V 1206	CL31B106KBK6PJE	Samsung	1276-CL31B106KBK6PJECT-ND	187-CL31B106KBK6PJE	C43935922	–	–	✔	✔	1
D1-D3	Green SMD LED diagnostic 0603	150060VS75000	Wurth Elektronik	732-4980-1-ND	710-150060VS75000	C6848499	-	-	✔	✔	3
J1	20-pin 0.4mm pitch BtB plug	DF40C-20DP-0.4V(51)	Hirose	H11618CT-ND	798-DF40C20DP0.4V51	C424637	-	Mouser lists as DF40C-20DP-0.4V(51) — search by Mouser PN 798-DF40C20DP0.4V51	✔	✔	1
J2-J5	1x5 2.54mm male THT	PH1-05-UA	Adam Tech	2057-PH1-05-UA-ND	737-PH1-05-UA	C5374051	-	manually-fit	✔	✔	4
R1-R3	330Ω 1% 0402	ERJ-2RKF3300X	Panasonic	P330LCT-ND	667-ERJ-2RKF3300X	C278592	-	-	✔	✔	3
R4-R5	10kΩ 1% 0402	ERJ-2RKF1002X	Panasonic	P10.0KLCT-ND	667-ERJ-2RKF1002X	C191123	-	-	✔	✔	2
SW1-SW2	SPST NO tactile THT	B3F-1070	Omron	SW406-ND	653-B3F-1070	C726011	-	-	✔	✔	2
U1	Local actuation controller LQFP32	STM32G071K8T3TR	STMicroelectronics	497-STM32G071K8T3TR-ND	511-STM32G071K8T3TR	-	Global sourcing	JLCPCB consignment only	✔	✔	1

The servo motor and the home switch are off-board electromechanical items and are therefore specified by the host mechanical assembly rather than as AM PCB-fitted BOM rows.

7. Thermal & ESD

• Thermal: No active cooling required on the AM. U1 (STM32G071K8T3TR LQFP-32) dissipates well below 100 mW; no heatsinking required.
• ESD - J1 (DF40C host dock, no TVS required): J1 mates to the host board (Extension J9 or Controller J11). It is not operator-accessible during live rotor swap and is explicitly outside DEC-048 scope per design/Electronics/Extension/Design_Spec.md §5. No TVS required per design/Standards/Global_Routing_Spec.md §9.
• ESD - J2-J5 (manual-fit loom/service headers, no TVS required): All remaining connectors (Adam Tech PH1-05-UA) are internal assembly headers; not accessible under live conditions. No TVS required per design/Standards/Global_Routing_Spec.md §9.

8. Mechanical & Silkscreen

• Data Plate: Per design/Standards/Global_Routing_Spec.md §6 on Layer L4, Revision Block text: STELLWERK [Actuation Module] V1.0.