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Updated Instruction Encoding (markdown)

Hayden Kroepfl 2018-01-20 12:36:54 -07:00
parent 9bf4d68769
commit a5f1df0489
1 changed files with 4 additions and 4 deletions
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Instruction-Encoding.md

@ -16,10 +16,10 @@ Selectors are 5-bit values that determine the addressing mode and registers invo
| Selector Type | Bit-pattern | Description | | Selector Type | Bit-pattern | Description |
| --- | --- | --- | | --- | --- | --- |
| REGISTER_16 | `00xxx` | Value in register `xxx` | | REGISTER_16 | `00000`-`01000` | Value in register (`0001` - `1000`) |
| MEMORY_IMM16 | `11110` | Address stored at operand word | | MEMORY_IMM16 | `11110` | Address stored at operand word |
| MEMORY_REG16 |`01xxx` | Address stored in register `xxx` | | MEMORY_REG16 |`01001` - `10000` | Address stored in register (`0001` - `1000`) |
| MEMORY_REG_DISP16 |`10xxx` | Address stored in register `xxx` plus offset in operand word | | MEMORY_REG_DISP16 |`10001` - `11000` | Address stored in register (`0001` - `1000`) plus offset in operand word |
| IMMEDIATE16 | `11111` | Immediate value at operand word | | IMMEDIATE16 | `11111` | Immediate value at operand word |
### Register Indexes ### Register Indexes
@ -35,7 +35,7 @@ Selectors are 5-bit values that determine the addressing mode and registers invo
| BP | | | | BP | | |
## Supplemental Words ## Supplemental Words
If either the destination or source require a 16-bit immediate value as part of their addressing mode, then one or two additional word will be suffixed to the basic instruction word. If both a source and destination supplimental word are required, then the source word will come first in order. If either the destination or source require a 16-bit immediate value as part of their addressing mode, then one or two additional word will be suffixed to the basic instruction word. If both a source and destination supplemental word are required, then the source word will come first in order.
| Word 0 | Word 1 | Word 2 | | Word 0 | Word 1 | Word 2 |
| --- | --- | --- | | --- | --- | --- |