I started with a ship full of max-level veterans, and I'm just a complete noob.

The following morning, the door to the Fifth Academy's engineering demonstration room was locked from the inside. Ren Xinmin pinned the three-page logic architecture diagram to the whiteboard, and with a red pencil, he traced the cross-page number all the way to the zero register, pressing a heavy circle into the paper.

He placed the manuscript he had independently recalculated the previous night face down on the corner of the table, without revealing his conclusion to Jiang Ming. He simply handed over the red pencil, waiting for another derivation path to provide the answer.

Jiang Ming took the pencil and reconnected the master clock, interrupt controller, and asynchronous reset terminal into a signal chain. Then he wrote a number next to the circle.

512.

Ren Xinmin stared at the number, then reached out and flipped open his scratch paper, which was densely covered with the entire sequence from the initial state to the register flip.

"The danger range I calculated is between 510 and 515. Device delays will cause deviations in the edge landing point, and the dead point of the logic count is still 512."

Jiang Ming aligned the page cross lines of the sixth and ninth modules. The register in the red circle adopts a nine-bit counting structure. The first nine inputs are responsible for fault accumulation, while the last output bypasses the program protection and is directly connected to the asynchronous reset terminal of the master clock.

Viewing any page individually, this connection can be interpreted as maintenance zeroing; only by piecing the three modules together in signal order will the hidden counting chain be revealed.

The nine-bit binary register is incremented from zero, and the total number of states it can hold is exactly 512. After the 511th interrupt, the register surface will still flip normally.

When the next interrupt arrives, all bits return to zero simultaneously, the overflow pulse enters the asynchronous reset terminal along the bypass, the master clock is forcibly cleared, but the detection circuit retains the trigger condition.

When the master clock restarts, the detection branch sends out a reset signal again, and the entire computing unit is locked into a loop of repeated zeroing.

"If it were a common design oversight, the fault point would not be stuck on the complete binary boundary, and the overflow output would not be specifically sent to the asynchronous reset terminal."

Jiang Ming used a pencil to mark the thin line spanning the page, mentally listing the sources of interruption in the flight procedure one by one: attitude correction, radar clutter, clock deviation, and external detection would all consume the count margin.

"It performs well enough in the first 500 tests. Ground acceptance tests usually don't reach that number. Short-term sampling will only yield a set of stable, fast, and interference-resistant results."

Ren Xinmin pushed over the summary of the interruption statistics of the Jiuquan firing range. Only the frequency range was kept on the paper, and the location and model had been hidden in accordance with the confidentiality regulations.

"After entering the complex clutter region, the accumulation velocity will increase, and the mid-flight phase is sufficient to push it to 512."

Jiang Ming substituted the data into the timing table, and the pencil slid from the takeoff point to the middle of the program, eventually stopping at the position where the rudder inputs were most frequently updated.

If the guidance computer stops updating at this point, the gyroscope platform will continue to send attitude signals, but the actuators will not receive new instructions, and the missile will deviate from the intended trajectory with its last control action.

Ground telemetry may still be able to detect the power supply status. At first glance, investigators will only notice that the clock is repeatedly starting up, making it difficult to immediately trace the counting bypasses scattered in the three volumes of documents.

Ren Xinmin took back the red pencil and drew two horizontal lines under 512. The anger that had been building up in his chest was now pressing down on his wrist, and the pencil made a dry, hard sound when it tapped on the table.

"Tomorrow is the final review. This bomb needs to be dismantled in front of everyone. We can't give them another chance to change the diagram or the explanation."

"We still lack concrete evidence."

Jiang Ming flipped the logic diagram to the blank back and began drawing the device connections for the analog unit. The paper derivation could lock in the risks, but it was not enough to make all the old-school experts immediately abandon the entire technology package.

More importantly, they need to prove that the trap can be removed, lest the Soviets use this as an excuse to claim that the Chinese can only identify the problem and still need to rely on the original design team to make modifications.

There were two knocks on the door of the engineering room, followed by a greeting in Russian from the Soviet assistant. The staff on duty checked the list before letting the person in.

The assistant, carrying a blue memo, entered the room and first glanced at the whiteboard. The red circle on the zero-reset register had been turned over, leaving only a page full of ordinary interface numbers.

"The Technical Committee hopes that China will expedite the acceptance process. The Joint Control Memorandum has been revised, and a formal response should be given at tomorrow's meeting."

The translator handed the document to the table, and the assistant pressed his finger on the signature column, reminding him that this memo would determine the order of supply for subsequent components, calculation data, and manufacturing materials.

Jiang Ming checked the cover number and the seal across the seam, signed the receipt date, and then had Ren Xinmin confirm on the duplicate that the document was only for review purposes.

"The project acceptance will proceed according to the established procedures, and feedback will be provided at the meeting tomorrow."

The assistant was clearly dissatisfied with the answer, but found the comfort he sought in the complex connections on the whiteboard. He closed his briefcase and left with a smug reminder before departing.

"Complete logic requires long-term training; relying solely on group verification can easily misidentify normal protection as an error."

After the door closed again, Ren Xinmin looked at the joint control memorandum, picked up a red pencil, and drew a diagonal line outside the signature column.

"He believes we're still stuck in the blueprints."

Jiang Ming locked the memo in a temporary filing cabinet, then spread out the reverse reconstruction diagram. He first cut off the direct connection between the overflow output and the asynchronous reset terminal, and then added a state discrimination and pulse absorption branch.

The original maintenance and reset function must be retained; otherwise, the Soviets could use the missing function to accuse China of modifying the system. The bypass module must only absorb the narrow pulses of the count overflow, while allowing real fault signals to enter the zeroing terminal.

He listed three sets of constraints on the paper: normal maintenance reset must pass, a single external fault must be responded to, and the master clock must continue to run after the continuous interruption count crosses 512.

Ren Xinmin picked up another pencil and added the trigger sequence of the gate from the overall input terminal. The two lines connected in the middle of the paper, and the first version of the bypass reconstruction circuit gradually took shape.

The sound of a document holder closing came from the corridor. Comrade Song stopped a confidential clerk who was about to approach the engineering office and asked him to show the borrowing approval document and document delivery slip for that day.

The identification the man handed over bore the seal of a temporary secondment from the Fifth Academy, but the delivery slip only listed the General Office, not the Engineering Demonstration Office.

"Hand the documents over to the desk; you cannot enter this section of the corridor."

Comrade Song turned the document over and found that the secondment period expired on the same day, and the corners of the photo also showed signs of peeling due to the re-lamination.

The confidential staff member reached out to retrieve his credentials, but pulled his fingers back after touching the edge of the plastic seal. He simply said he had gone to the wrong floor, then turned towards the stairwell with the documents tucked inside.

Comrade Song signaled the guards to follow him downstairs, then took his identification number and entered the engineering office to record what had just happened in the security log.

Jiang Ming checked the number but did not draw any conclusions about the visitor's identity. He only requested that the engineering department change the delivery process from this moment on, and that all documents be handed over by a designated duty officer in the outer room.

The evidence they had was still on paper, and those who were close to the engineering office might have indeed taken the wrong route. But at the critical juncture of the Soviet Union's urging for the signing, no overstepping of the line could be considered a mere oversight.

Ren Xinmin rolled the reconstruction diagram into a cardboard tube and handed it to Jiang Ming to take back to 502 for device-level reproduction, while he stayed behind to organize the Jiuquan interrupt density and overall interface data.

As Jiang Ming walked to the door, he glanced back at the whiteboard. The back of the logic diagram he had flipped over was completely empty, with the red circle and 512 hidden on a side where no one could see them.

At the end of the corridor, the confidential clerk had already left, but an unregistered manila envelope remained on the duty desk.

Comrade Song put on gloves and turned the bag over. On the cover, in the recipient section, it read "Engineering Demonstration Office".