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Professional electrical schematic diagram in strict GOST ESKD style (Russian standard), black and white technical drawing on pure white background. High contrast, vector line art style, no shading, no colors, no gradients. 

CENTRAL COMPONENT: 
A large rectangular symbol for Microcontroller DD1 "ATmega32U4" located in the exact center of the canvas. Size approx 400x500 units. 
- Left side pins (top to bottom): XTAL1 (pin 9), XTAL2 (pin 10), RESET (pin 11), PB0-PB7 (pins 12-19), PD0-PD7 (pins 20-28). 
- Right side pins (top to bottom): VBUS (pin 44), GND (pins 13, 43), AVCC (pin 42), AREF (pin 40), VCC (pins 24, 36), UCAP (pin 17), PF0-PF7/ADC (pins 31-36), PE2, PE6 (pins 37-38), PC6, PC7 (pins 29-30).
- Text inside rectangle: "DD1", "ATmega32U4", "TQFP-44". Font: GOST typeface (cyrillic technical font), bold, black.

LEFT SIDE - USB INTERFACE (XS1):
- Connector symbol XS1 "USB Type-A" (vertical rectangle with internal contacts) at far left. 
- Pin 1 (VBUS) connects via wire to Resistor R4 (zigzag symbol, label "R4 1k"), then to DD1 pin 44. 
- Capacitor C7 (two parallel lines symbol, label "C7 10µF") connects from VBUS line to Ground bus.
- Pin 2 (D-) connects via wire to Resistor R2 (zigzag, label "R2 22Ω"), then to DD1 pin 14.
- Pin 3 (D+) connects via wire to Resistor R1 (zigzag, label "R1 22Ω"), then to DD1 pin 15.
- Pin 4 (GND) connects directly to common Ground bus.

TOP CENTER - CLOCK CIRCUIT:
- Quartz resonator Y1 (rectangle symbol with two lines inside, label "Y1 16MHz") positioned above DD1.
- Y1 left terminal connects to DD1 pin 9 (XTAL1). Capacitor C1 (label "C1 22pF") connects from this line to Ground.
- Y1 right terminal connects to DD1 pin 10 (XTAL2). Capacitor C2 (label "C2 22pF") connects from this line to Ground.

POWER & RESET CIRCUITRY:
- Resistor R3 (zigzag, label "R3 10kΩ") connects DD1 pin 11 (RESET) to VCC power rail.
- Decoupling capacitors C3, C4, C5, C6 (all labeled "100nF") placed near VCC and AVCC pins of DD1, connecting power rails to Ground.
- Capacitor C8 (label "C8 1µF") connects DD1 pin 17 (UCAP) to Ground.

RIGHT SIDE - OUTPUT CONNECTORS:
- Connector XP1 (double row of circles/dots symbol, 2x8 pins) at top right. Label "XP1 PORTS B/D". Wires connect from DD1 pins 12-28 (Ports B and D) to XP1 pins.
- Connector XP2 (single row of circles, 8 pins) below XP1. Label "XP2 ADC (PORT F)". Wires connect from DD1 pins 31-36 (PF0-PF7) plus AREF and AVCC to XP2.
- Connector XP3 (single row, 4 pins) below XP2. Label "XP3 CONN A". Connects to DD1 pins 29-30 (PC6, PC7) + VCC/GND.
- Connector XP4 (single row, 4 pins) below XP3. Label "XP4 CONN B". Connects to DD1 pins 37-38 (PE2, PE6) + VCC/GND.
- Connector XP5 (single row, 4 pins) at bottom right. Label "XP5 CONN C". Connects to specific ADC pins + VCC/GND.

GROUND AND POWER BUSSES:
- Horizontal solid black lines for "+5V" (VCC) and "GND" running along top and bottom edges.
- Standard GOST ground symbol (three horizontal lines decreasing in width) used at multiple points.
- All wires are straight orthogonal lines (90-degree angles only), no curves. Junction dots (black filled circles) at every wire intersection/connection point.

TEXT LABELING:
- All component designators (R1, C1, DD1, etc.) and values (22Ω, 10k, 16MHz) in black sans-serif technical font.
- Net names (D+, D-, VBUS, XTAL1, etc.) written near corresponding wires.
- Title block (stamp) in bottom right corner: "Макетная плата ATmega32U4", "Лист 1", "Изм.", "Подп.", "Дата".

STYLE PARAMETERS:
- Line weight: 0.5mm for wires, 0.7mm for component outlines.
- Pure black ink on pure white paper texture.
- No shadows, no 3D effects, no color fills.
- Technical precision, engineering blueprint aesthetic.
- Aspect ratio 16:9 or A3 landscape layout.