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DP offset instructions, new demo programs.

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Added DPUP and DPDN, which take a one byte operand specifying how far up or down to offset the Data Pointer.
Three Fibonacci generators using the print.asm library.
 - 8 bit values printing in decimal representation.
- 16 bit values printing in hexadecimal representation.
- 32 bit values printing in hexadecimal representation.
This commit is contained in:
Anachronaut
2024-11-01 12:13:13 -04:00
committed by GitHub
parent e5241beb51
commit f4c78e68ba
7 changed files with 332 additions and 90 deletions
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SplitBit Programming Manual.md
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@@ -16,22 +16,20 @@ It has six registers:
## List of Instructions:
### Arithmetic and Logic Operations: 11 Instructions
### Arithmetic and Logic Operations: 9 Instructions
Hex Code | Mnemonic | Description
-- | -- | --
00 | ADD | Adds A, B, and the Carry Flag, the result is stored in Q.
01 | SUB | Subtracts B and the Carry Flag from A, the result is stored in Q.
02 | AND | Bitwise and of A and B, the result is stored in Q.
03 | OR | Bitwise or of A and B, the result is stored in Q.
04 | NOR | Bitwise nor of A and B, the result is stored in Q.
05 | NAND | Bitwise nand of A and B, the result is stored in Q.
06 | XOR | Bitwise xor of A and B, the result is stored in Q.
07 | NOTA | Bitwise inversion of A, the result is stored in Q.
08 | NOTB | Bitwise inversion of B, the result is stored in Q.
09 | SHL | A and B form a circular shift register. Rotate this register left.
0A | SHR | A and B form a circular shift register. Rotate this register right.
04 | XOR | Bitwise xor of A and B, the result is stored in Q.
05 | NOTA | Bitwise inversion of A, the result is stored in Q.
06 | NOTB | Bitwise inversion of B, the result is stored in Q.
07 | SHL | A and B form a circular shift register. Rotate this register left.
08 | SHR | A and B form a circular shift register. Rotate this register right.
### Branch Operations: 11 Instructions
### Branch and Subroutine Operations: 7 Instructions
Hex Code | Mnemonic | Description
-- | -- | --
10 | BRI | Branch Immediately. Loads the immediate next two bytes of Program Memory into the Program Counter, first the most significant byte, then the least.
@@ -40,10 +38,6 @@ Hex Code | Mnemonic | Description
13 | BRB | Branch on B. If B is zero, loads the immediate next two bytes of Program Memory into the Program Counter.
14 | BRC | Branch if Carry is set.
17 | CALL | Call subroutine. Stores all the registers to the Stack, A, B, Q, the Data Pointer, and the Program Counter, then performs an immediate branch.
18 | CALLA | Conditional Call on A. Calls subroutine if A is zero.
19 | CALLB | Conditional Call on B. Calls subroutine if B is zero.
1A | CALLQ | Conditional Call on Q. Calls subroutine if Q is zero.
1B | CALLCF | Conditional Call on Carry. Calls subroutine if the Carry Flag is set.
1F | RET | Restores all registers from the Stack, then immediately branches to the Return Address by setting the Program Counter to the next instruction after the last CALL.
@@ -73,17 +67,19 @@ Hex Code | Mnemonic | Description
35 | POPB | Reads the location referenced by the Stack Pointer from Data Memory into B then increments the Stack Pointer.
36 | POPD | Restores the Program Counter from the top two bytes in the stack, increments the Stack Pointer by two.
### Data Operations: 8 Instructions
### Data Operations: 10 Instructions
Hex Code | Mnemonic | Description
-- | -- | --
40 | INCD | Increments the Data Pointer.
41 | DECD | Decrements the Data Pointer.
42 | LDA | Loads the byte referenced from Data Memory by the Data Pointer into A.
43 | LDB | Loads the byte referenced from Data Memory by the Data Pointer into B.
44 | STQ | Stores Q into the byte referenced by the Data Pointer in Data Mmoery.
44 | STQ | Stores Q into the byte referenced by the Data Pointer in Data Memory.
45 | STA | Stores A into the byte referenced by the Data Pointer in Data Memory.
46 | STB | Stores B into the byte referenced by the Data Pointer in Data Memory.
47 | SETD | Loads the next two bytes of Program Memory into the Data Pointer.
48 | DPUP | Offset Data Pointer up by the value of the immediate next byte of Program Memory.
49 | DPDN | Offset Data Pointer down by the value of the immediate next byte of Program Memory.
### Output Operations: 3 Instructions