Differences

This shows you the differences between two versions of the page.

--- sd-8516_technical_manual [2025/12/24 04:18] – appledog
+++ sd-8516_technical_manual [2026/01/08 17:15] (current) – removed appledog
@@ Line 1: / Line 1: @@
-= SD-8516 Technical Manual
-== Introduction
-The **Stellar Dynamics SD-8516** represents a categorical reimagining of microprocessor architecture. This 16-bit CPU, implemented in AssemblyScript for the VC-3 computer system, delivers performance exceeding conventional silicon constraints through advanced cross-boundary resonance microcascades.
-**Key Specifications:**
-* 16-bit architecture with 16 general-purpose registers
-* Clock speed: 10-20 MHz (targeting 3-5 MIPS)
-* Memory: 256KB addressable via 4-bank system
-* ~20× performance improvement over legacy 8510 design
-== System Lore
-Since the days of the first minicomputers, Stellar Dynamics has been at the forefront of microarchitecture design. The SD-8516 is not simply an iteration upon its predecessors; it is a categorical reimagining of what a "processor" can be when unshackled from quantum locality.
-While our earliest designs struggled with resonance cascade instability, the SD-8516 delivers stable, predictable cross-boundary resonance microcascades at clock rates exceeding the theoretical limits of conventional silicon.
-These advancements position the Stellar Dynamics SD-8516 as the definitive architecture for next-generation computation: a bridge between classical logic engines and the emergent technologies of multidimensional processing.
-== CPU Architecture
-=== Register Set
-The SD-8516 features sixteen 16-bit registers:
-|= Register |= Name |= Primary Use |
-| R0  | A | Accumulator |
-| R1  | B | Accumulator |
-| R2  | X | Index/General |
-| R3  | Y | Index/General |
-| R4  | I | Loop/General |
-| R5  | J | Loop/General |
-| R6  | K | Loop/General |
-| R7  | T | Temporary/General |
-| R8  | M | Memory Pointer |
-| R9  | D | Memory Pointer |
-| R10 | E | Extra/General |
-| R11 | C | Counter/General |
-| R12 | F | Function Register |
-| R13 | G | General Purpose |
-| R14 | L | General Purpose |
-| R15 | Z | General Purpose |
-**Note:** The SD-8516 does not use register pairing except for multiplication operations, which store results in the AB register pair.
-=== Register Encoding
-Registers are encoded as 4-bit values (0-15), allowing two registers per byte:
-* Low nibble: First operand
-* High nibble: Second operand
-Example: {{{ADD A, B}}} encodes as {{{0x01}}} (A=0, B=1)
-=== Flags Register
-The 16-bit FLAGS register contains:
-**Arithmetic Flags (Byte 1):**
-* Bit 0: **Z** (Zero) - Result was zero
-* Bit 1: **N** (Negative) - Result was negative (bit 15 set)
-* Bit 2: **C** (Carry) - Unsigned overflow/borrow
-* Bit 3: **V** (Overflow) - Signed overflow
-* Bits 4-7: Reserved
-**Control Flags (Byte 2):**
-* Bit 8: **H** (Halt) - CPU stopped, waiting for interrupt
-* Bit 9: **T** (Trace) - Single-step debugging mode
-* Bit 10: **B** (Breakpoint) - Breakpoint mode active
-* Bit 11: **E** (Exception) - Sticky error flag
-* Bit 12: **P** (Protected) - Protected mode enabled
-* Bit 13: **I** (Interrupt) - Interrupt enable/disable
-* Bit 14: **S** (Sound) - Sound System Interrupt enable
-* Bit 15: Reserved
-Layout: {{{Z N C V - - - - H T B E P I S -}}}
-== Memory Architecture
-=== Memory Map
-|= Address Range |= Description |
-| $0000-$00FF | Zero page / System variables |
-| $0100-$DFFF | User program space |
-| $E000-$EFFF | KERNAL ROM (4KB) |
-| $F000-$F3E7 | Video text buffer (1000 bytes) |
-| $F800-$FBFF | Video color buffer (1000 bytes) |
-| $E800-$E8FF | Character ROM (2048 bytes) |
-=== Bank Addressing
-The SD-8516 supports 4 banks of 64KB each (256KB total) through special addressing modes:
-{{{
-LDA [I:J]        ; Load from bank I, offset J
-STA [2:$1000]    ; Store to bank 2, offset $1000
-}}}
-**Bank allocation:**
-* Bank 0: System RAM, program space
-* Bank 1: Audio samples and sound registers
-* Bank 2: Primary video framebuffer + palette
-* Bank 3: Secondary video buffer (high-resolution modes)
-=== System Variables
-|= Address |= Description |
-| $EF00 | Video mode register |
-| $EF01 | Column count (40 or 80) |
-| $EF02 | Row count (25) |
-| $EF03 | Character width (8) |
-| $EF04 | Character height (8) |
-| $EF05-$EF08 | Hardware clock (32-bit milliseconds) |
-| $EF09 | Default character color |
-| $EF0A | Cursor color |
-| $EF0B | Color palette mode (0=COLORDORE, 1=CGA 5153) |
-| $EF10 | Cursor X position |
-| $EF11 | Cursor Y position |
-| $EF12 | Cursor blink state |
-| $EF20 | Keyboard status flags |
-| $EF21 | Keyboard buffer count |
-| $EF22-$EF31 | Keyboard buffer (16 bytes) |
-== Instruction Set Architecture
-=== Load/Store Instructions
-|= Opcode |= Mnemonic |= Description |= Bytes |
-| 00 | LD_IMM | Load immediate word | 3 |
-| 01 | LD_IMMB | Load immediate byte | 2 |
-| 02 | LD_IMMW | Load immediate word | 3 |
-| 03 | LD_MEM | Load from memory (indirect) | 3 |
-| 04 | LD_MEMB | Load byte from memory | 3 |
-| 05 | LD_MEMW | Load word from memory | 3 |
-| 06 | LD_RI | Load from register indirect | 2 |
-| 07 | LD_RIB | Load byte from register indirect | 2 |
-| 08 | LD_RIW | Load word from register indirect | 2 |
-| 09 | ST_MEM | Store to memory | 5 |
-| 0A | ST_MEMB | Store byte to memory | 5 |
-| 0B | ST_MEMW | Store word to memory | 5 |
-**Examples:**
-{{{
-LDA #$1234       ; Load immediate $1234 into A
-LDAL #$42        ; Load immediate byte $42 into AL
-LDA [$F000]      ; Load word from address $F000
-STA [2:$1000]    ; Store A to bank 2, offset $1000
-}}}
-=== Arithmetic Operations
-|= Instruction |= Description |= Flags Affected |
-| ADD | Add | Z, N, C, V |
-| ADDB | Add bytes | Z, N, C, V |
-| SUB | Subtract | Z, N, C, V |
-| SUBB | Subtract bytes | Z, N, C, V |
-| MUL | Multiply (result in AB) | Z, N |
-| MULB | Multiply bytes | Z, N |
-| DIV | Divide (quotient in A, remainder in B) | Z, N |
-| DIVB | Divide bytes | Z, N |
-| MOD | Modulo | Z, N |
-| MODB | Modulo bytes | Z, N |
-| INC | Increment | Z, N |
-| DEC | Decrement | Z, N |
-=== Logic Operations
-|= Instruction |= Description |= Flags Affected |
-| AND | Bitwise AND | Z, N |
-| ANDB | Bitwise AND (byte) | Z, N |
-| OR | Bitwise OR | Z, N |
-| ORB | Bitwise OR (byte) | Z, N |
-| XOR | Bitwise XOR | Z, N |
-| XORB | Bitwise XOR (byte) | Z, N |
-| NOT | Bitwise NOT | Z, N |
-| NOTB | Bitwise NOT (byte) | Z, N |
-| TEST | Bitwise AND (no write) | Z, N |
-| TESTB | Bitwise AND byte (no write) | Z, N |
-=== Shift/Rotate Operations
-|= Instruction |= Description |= Flags Affected |
-| SHL | Shift left | Z, N, C |
-| SHLB | Shift left byte | Z, N, C |
-| SHR | Shift right | Z, N, C |
-| SHRB | Shift right byte | Z, N, C |
-| ROL | Rotate left | Z, N, C |
-| ROLB | Rotate left byte | Z, N, C |
-| ROR | Rotate right | Z, N, C |
-| RORB | Rotate right byte | Z, N, C |
-=== Comparison & Branching
-|= Instruction |= Description |= Flags Affected |
-| CMP | Compare (subtract, discard result) | Z, N, C, V |
-| CMPB | Compare bytes | Z, N, C, V |
-| JMP | Unconditional jump | None |
-| JZ | Jump if zero | None |
-| JNZ | Jump if not zero | None |
-| JC | Jump if carry set | None |
-| JNC | Jump if carry clear | None |
-| JN | Jump if negative | None |
-| JNN | Jump if not negative | None |
-| JV | Jump if overflow | None |
-| JNV | Jump if no overflow | None |
-| JL | Jump if less (signed) | None |
-| JNL | Jump if not less | None |
-| JG | Jump if greater (signed) | None |
-| JNG | Jump if not greater | None |
-=== Subroutine Operations
-|= Instruction |= Description |
-| CALL | Call subroutine (push IP, jump) |
-| RET | Return from subroutine (pop IP) |
-| PUSH | Push register to stack |
-| POP | Pop from stack to register |
-| PUSHA | Push all registers |
-| POPA | Pop all registers |
-=== System Operations
-|= Instruction |= Description |
-| NOP | No operation |
-| HALT | Halt CPU (set H flag) |
-| INT | Software interrupt |
-| TICK | Performance counter tick |
-| SSI | Enable Sound System Interrupts |
-| CSI | Clear Sound System Interrupts |
-| SEC | Set carry flag |
-| CLC | Clear carry flag |
-| SEZ | Set zero flag |
-| CLZ | Clear zero flag |
-| SEN | Set negative flag |
-| CLN | Clear negative flag |
-| SEV | Set overflow flag |
-| CLV | Clear overflow flag |
-== Sound System (SD-450)
-The SD-8516 is paired with the SD-450 sound subsystem, featuring 4 independent voices with ADSR envelopes.
-=== Voice Architecture
-Each voice occupies 16 bytes of memory in Bank 1:
-|= Offset |= Register |= Description |
-| +$00 | FREQ_LO | Frequency low byte |
-| +$01 | FREQ_HI | Frequency high byte |
-| +$02 | GATE | Waveform/gate control |
-| +$03 | VOLUME | Volume (0-255) |
-| +$04 | ATTACK | Attack time |
-| +$05 | DECAY | Decay time |
-| +$06 | SUSTAIN | Sustain level |
-| +$07 | RELEASE | Release time |
-| +$08 | DATA1 | Pulse width / noise type |
-| +$09-$0F | Reserved | Future expansion |
-**Voice base addresses:**
-* Voice 0: {{{$ED00}}}
-* Voice 1: {{{$ED10}}}
-* Voice 2: {{{$ED20}}}
-* Voice 3: {{{$ED30}}}
-=== Waveforms
-Gate register values:
-* 0: Silent (gate off)
-* 1: Square wave
-* 2: Triangle wave
-* 3: Sawtooth wave
-* 4: Sine wave
-* 5: Pulse wave (variable width via DATA1)
-* 6: White/pink/brown noise (type via DATA1)
-=== ADSR Envelope
-The Attack-Decay-Sustain-Release envelope shapes each note:
-* **Attack:** Time to reach peak volume (0-255 × 10ms)
-* **Decay:** Time to decay to sustain level (0-255 × 10ms)
-* **Sustain:** Held volume level (0.0-1.0 of peak)
-* **Release:** Time to fade to silence after gate off (0-255 × 10ms)
-**Example:**
-{{{
-; Play middle C on voice 0
-LDA $112B           ; C4 frequency (262 Hz / 0.0596)
-STA [$ED00]         ; FREQ_LO/HI
-LDAL $01            ; Square wave
-STAL [$ED02]        ; GATE
-LDAL $4D            ; ~30% volume
-STAL [$ED03]        ; VOLUME
-}}}
-== Video System
-=== Video Modes
-The VC-3 supports both text and graphics modes:
-|= Mode |= Resolution |= Colors |= Description |
-| 1 | 40×25 text | 16 | Character mode, COLORDORE palette |
-| 2 | 80×25 text | 16 | High-res text, CGA 5153 palette |
-| 3 | 320×200 | 16 | Packed pixels (4-bit) |
-| 4 | 256×224 | 256 | SNES-style mode |
-| 8 | 128×128 | 16 | Low-res mode |
-=== Text Mode Architecture
-**Mode 1 (40×25):**
-* Character buffer: {{{$F000-$F3E7}}} (1000 bytes)
-* Color buffer: {{{$F800-$FBE7}}} (1000 bytes)
-* Character ROM: {{{$E800-$E8FF}}} (256 characters × 8 bytes)
-**Color byte format:** {{{(bg_color << 4) | fg_color}}}
-**Mode 2 (80×25):**
-* Same layout, 2000 bytes each
-* Scanline doubling for 640×400 output
-=== Graphics Mode Architecture
-**Mode 3 (320×200×16):**
-* Framebuffer: Bank 2, {{{$00000-$07CFF}}} (32,000 bytes)
-* Palette: Bank 2, {{{$F000-$F02F}}} (16 colors × 3 bytes RGB)
-* Pixel packing: 2 pixels per byte (high/low nibbles)
-**Pixel addressing:**
-{{{
-offset = (y × 160) + (x ÷ 2)
-address = Bank 2 + offset
-}}}
-**Mode 4 (256×224×256):**
-* Framebuffer: Bank 2, {{{$00000-$DFFFF}}} (57,344 bytes)
-* Palette: Bank 2, {{{$F000-$F2FF}}} (256 colors × 3 bytes RGB)
-* 1 byte per pixel (256 colors)
-=== Palette Format
-Each palette entry is 3 bytes (RGB):
-{{{
-Offset +0: Red (0-255)
-Offset +1: Green (0-255)
-Offset +2: Blue (0-255)
-}}}
-== KERNAL Functions
-The KERNAL ROM provides system services at {{{$E000}}}:
-=== Input/Output
-**GETKEY** - Read keyboard buffer
-{{{
-IN:  None
-OUT: A = ASCII character (if available)
-     B = previous buffer count
-}}}
-**WRITE_CHAR** - Write character to screen
-{{{
-IN:  A = character code
-     X = column (0-39/79)
-     Y = row (0-24)
-}}}
-**WRITE_STRING** - Write null-terminated string
-{{{
-IN:  A = string address (low byte)
-     B = string address (high byte)
-     X = column
-     Y = row
-}}}
-=== Cursor Management
-**CTOXY** - Move cursor
-{{{
-IN:  X = column
-     Y = row
-}}}
-**GETCURSOR** - Read cursor position
-{{{
-OUT: X = column
-     Y = row
-}}}
-=== String Utilities
-**STRLEN** - Get string length
-{{{
-IN:  A = string address (low byte)
-     B = string address (high byte)
-OUT: A = length (low byte)
-     B = length (high byte)
-     C = carry flag if > 256 bytes
-}}}
-**BYTETOSTR** - Convert byte to decimal string
-{{{
-IN:  A = byte value (0-255)
-     X = destination address (low)
-     Y = destination address (high)
-OUT: Zero-terminated string at XY
-}}}
-=== Arrow Key Handlers
-* **ARR_LEFT** - Move cursor left (bounded)
-* **ARR_RIGHT** - Move cursor right (bounded)
-* **ARR_UP** - Move cursor up (bounded)
-* **ARR_DOWN** - Move cursor down (bounded)
-== Assembly Language
-=== Syntax
-**Labels:**
-{{{
-loop:               ; Define label
-    JMP @loop       ; Reference label with @
-}}}
-**Immediates:**
-{{{
-LDA #$1234          ; Hexadecimal
-LDA #100            ; Decimal
-LDAL #'A'           ; Character literal
-}}}
-**Comments:**
-{{{
-; Single-line comment
-}}}
-**Data Directives:**
-{{{
-.equ CONSTANT $1234         ; Define constant
-.bytes "Hello", 0           ; Byte array
-.word $1234, $5678          ; Word array
-}}}
-=== Example Programs
-**Hello World:**
-{{{
-    LDA @MSG
-    LDX #0
-    LDY #0
-    CALL @WRITE_STRING
-    RET
-MSG:
-    .bytes "HELLO WORLD!", 0
-}}}
-**Fill Screen with Stars:**
-{{{
-    LDAL #'*'           ; Character to draw
-    LDX #0              ; Start column
-    LDY #0              ; Start row
-loop:
-    CALL @WRITE_CHAR
-    INC X
-    CMP X, #40
-    JNZ @loop
-    LDX #0              ; Reset column
-    INC Y
-    CMP Y, #25
-    JNZ @loop
-    RET
-}}}
-**Random Number Generator (Galois LFSR):**
-{{{
-.equ RND_SEED $EFF0
-rnd_init:
-    LDA [$EF05]         ; Hardware clock
-    LDB [$EF06]
-    XOR A, B
-    STA [@RND_SEED]
-    RET
-rnd_byte:
-    LDA [@RND_SEED]
-    MOV B, A
-    ANDB BL, $01        ; Check LSB
-    SHR A               ; Shift right
-    CMPB BL, $00
-    JZ @no_xor
-    LDB $B400           ; Polynomial
-    XOR A, B
-no_xor:
-    STA [@RND_SEED]
-    RET
-}}}
-== Performance Characteristics ==
-**Measured Performance:**
-* Clock speed: 10 MHz base, up to 100 MHz
-* Sustained MIPS: 60 MIPS (i7-12700k)
-* Memory bandwidth: ~280 MB/s
-* Sound system overhead: < 5% CPU time
-* Video refresh: 60 Hz (16.67ms frame time)
-**Optimization Notes:**
-* Batch instruction execution (787,401 instructions per batch at 100 MIPS target)
-* MessageChannel-based scheduling for low-latency loops
-* Time-debt throttling maintains consistent clock rate
-* Sound updates triggered by register writes (not polling)
-== Technical Implementation
-**Architecture:** WebAssembly-based virtual CPU
-**Languages:** AssemblyScript (CPU core), JavaScript (I/O systems)
-**Memory Model:** 4 banks of 64k RAM
-**Audio Backend:** SD-450 4 voice polyphonic 5 waveform Audio System
-**Video Backend:** 9 mode Text and Graphics pixel-perfect render engine
-== Appendix: Planned Features
-=== KERNAL Functions (In Development)
-# **print_byte** - Display 16-bit number at cursor
-# **print_char_at** - Single character without moving cursor
-# **clear_screen** - Fill screen with spaces
-# **print_at** - Positioned string output
-# **string_compare** - String equality test
-# **string_to_upper** - Case conversion
-# **wait_key** - Blocking key wait
-# **random_range** - Bounded random numbers
-# **draw_box** - Border rendering
-# **scroll_region** - Partial screen scrolling
-# **save_screen/restore_screen** - Screen buffer management
-=== Graphics Enhancements
-* Bresenham line drawing (implemented)
-* Sprite system with hardware acceleration
-* Tilemap support for scrolling backgrounds
-* Bitmap font rendering
-=== Sound Enhancements
-* PCM streaming for voice/SFX
-* Additional waveforms (filtered noise, PWM variants)
-* Other sample playback (Opus/Ogg compressed)
-* LFO and vibrato effects
----
-**SD-8516 Technical Manual** - Revision 1.0
-**Copyright © 2025 Appledog Hu**
-**All specifications subject to change as quantum resonance research continues.**