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authoroharboe <oharboe>2008-08-15 20:32:50 +0000
committeroharboe <oharboe>2008-08-15 20:32:50 +0000
commitcae9e8c62d8f3fd3900bd90148c20c90730324eb (patch)
treedcccae6d7fafc9f73495af36e6a150493522d215
parent0315a8cc7a7f58a8c539aa0e73fe6142ea44def0 (diff)
downloadzpu-cae9e8c62d8f3fd3900bd90148c20c90730324eb.zip
zpu-cae9e8c62d8f3fd3900bd90148c20c90730324eb.tar.gz
some more docs.
-rw-r--r--zpu/docs/zpu_arch.html133
1 files changed, 72 insertions, 61 deletions
diff --git a/zpu/docs/zpu_arch.html b/zpu/docs/zpu_arch.html
index 312bdb6..825f0d2 100644
--- a/zpu/docs/zpu_arch.html
+++ b/zpu/docs/zpu_arch.html
@@ -136,7 +136,6 @@ end if
Pop value off stack and store it in the SP+xxxxx*4 memory location, where xxxxx is a positive integer.
</td>
<td>
- Fix!
</td>
</tr>
<tr>
@@ -150,7 +149,7 @@ end if
Push value of memory location SP+xxxxx*4, where xxxxx is a positive integer, onto stack.
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -164,7 +163,7 @@ end if
Add value of memory location SP+xxxx*4 to value on top of stack.
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -175,10 +174,16 @@ end if
001x xxxx
</td>
<td>
- Push PC to stack and set PC to 0x0+xxxxx*32. This is used to emulate opcodes. See zpupgk.vhd for list of emulate opcode values used. zpu_core.vhd contains reference implementations of these instructions rather than letting the ZPU execute the EMULATE instruction
+ Push PC to stack and set PC to 0x0+xxxxx*32. This is used to emulate opcodes. See
+ zpupgk.vhd for list of emulate opcode values used. zpu_core.vhd contains
+ reference implementations of these instructions rather than letting the ZPU execute the EMULATE instruction
+ <p>
+ One way to improve performance of the ZPU is to implement some of
+ the EMULATE instructions.
+
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -192,7 +197,7 @@ end if
Pushes program counter onto the stack.
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -206,21 +211,7 @@ end if
Pops address off stack and sets PC
</td>
<td>
- Fix!
- </td>
- </tr>
- <tr>
- <td>
- LOAD
- </td>
- <td>
- 0000 1000
- </td>
- <td>
- Pops address stored on stack and loads the value of that address onto stack.
- </td>
- <td>
- Fix!
+
</td>
</tr>
<tr>
@@ -233,10 +224,13 @@ end if
<td>
Pops address stored on stack and loads the value of that address onto stack.
<p>
- Bit 0 and 1 of address are always 0.
+ Bit 0 and 1 of address are always treated as 0(i.e. ignored) by
+ the HDL implementations and C code is guaranteed by the programming
+ model never to use 32 bit LOAD on non-32 bit aligned addresses(i.e.
+ if a program does this, then it has a bug).
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -249,10 +243,10 @@ end if
<td>
Pops address, then value from stack and stores the value into the memory location of the address.
<p>
- Bit 0 and 1 of address are always 0
+ Bit 0 and 1 of address are always treated as 0
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -266,7 +260,7 @@ end if
Pushes stack pointer.
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -277,10 +271,10 @@ end if
0000 1101
</td>
<td>
- Used to allocate/deallocate space on stack for variables or when changing threads.
+ Pops value off top of stack and sets SP to that value. Used to allocate/deallocate space on stack for variables or when changing threads.
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -294,7 +288,7 @@ end if
Pops two values on stack adds them and pushes the result
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -308,7 +302,7 @@ end if
Pops two values off the stack and does a bitwise-and & pushes the result onto the stack
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -322,7 +316,7 @@ end if
Pops two integers, does a bitwise or and pushes result
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -337,7 +331,7 @@ end if
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -348,10 +342,12 @@ end if
0000 1010
</td>
<td>
- Reverses the bit order of the value on the stack, i.e. abc->cba, 100->001, 110->011, etc.
+ Reverses the bit order of the value on the stack, i.e. abc->cba, 100->001, 110->011, etc.
+ <p>
+ The raison d'etre for this instruction is mainly to emulate other instructions.
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -362,10 +358,11 @@ end if
0000 1011
</td>
<td>
- No operation, clears IDIM flag as side effect
+ No operation, clears IDIM flag as side effect, i.e. used between two
+ consequtive IM instructions to push two values onto the stack.
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -381,7 +378,7 @@ end if
pushIntStack(a+b);<br>
</td>
<td>
- Fix!
+
</td>
</tr>
@@ -396,7 +393,7 @@ end if
setPc(popIntStack()+getPc());
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -412,7 +409,7 @@ end if
pushIntStack(b-a);<br>
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -426,7 +423,7 @@ end if
pushIntStack(popIntStack() ^ popIntStack());
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -437,10 +434,13 @@ pushIntStack(popIntStack() ^ popIntStack());
51
</td>
<td>
+ 8 bit load instruction. Really only here for compatibility with
+ C programming model. Also it has a big impact on DMIPS test.
+ <p>
pushIntStack(cpuReadByte(popIntStack())&0xff);
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -451,12 +451,15 @@ pushIntStack(popIntStack() ^ popIntStack());
52
</td>
<td>
+ 8 bit store instruction. Really only here for compatibility with
+ C programming model. Also it has a big impact on DMIPS test.
+ <p>
addr = popIntStack();<br>
val = popIntStack();<br>
cpuWriteByte(addr, val);
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -467,10 +470,15 @@ pushIntStack(popIntStack() ^ popIntStack());
34
</td>
<td>
+
+ 16 bit load instruction. Really only here for compatibility with
+ C programming model.
+ <p>
+
pushIntStack(cpuReadWord(popIntStack()));
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -481,12 +489,15 @@ pushIntStack(popIntStack() ^ popIntStack());
35
</td>
<td>
+ 16 bit store instruction. Really only here for compatibility with
+ C programming model.
+ <p>
addr = popIntStack();<br>
val = popIntStack();<br>
cpuWriteWord(addr, val);
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -503,7 +514,7 @@ addr = popIntStack();<br>
pushIntStack((a < b) ? 1 : 0);<br>
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -520,7 +531,7 @@ addr = popIntStack();<br>
pushIntStack((a <= b) ? 1 : 0);
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -539,7 +550,7 @@ addr = popIntStack();<br>
pushIntStack((a < b) ? 1 : 0);
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -558,7 +569,7 @@ addr = popIntStack();<br>
pushIntStack((a <= b) ? 1 : 0);
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -582,7 +593,7 @@ addr = popIntStack();<br>
}
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -606,7 +617,7 @@ addr = popIntStack();<br>
}<br>
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -621,7 +632,7 @@ addr = popIntStack();<br>
pushIntStack(popIntStack() * popIntStack());
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -642,7 +653,7 @@ addr = popIntStack();<br>
pushIntStack(a / b);<br>
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -663,7 +674,7 @@ addr = popIntStack();<br>
pushIntStack(a % b); <br>
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -684,7 +695,7 @@ addr = popIntStack();<br>
pushIntStack(t);<br>
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -705,7 +716,7 @@ addr = popIntStack();<br>
pushIntStack(t);<br>
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -726,7 +737,7 @@ addr = popIntStack();<br>
</td>
<td>
- Fix!
+
</td>
</tr>
@@ -745,7 +756,7 @@ addr = popIntStack();<br>
setPc(address); <br>
</td>
<td>
- Fix!
+
</td>
</tr>
<tr>
@@ -762,7 +773,7 @@ int address = pop();<br>
push(pc + 1);<br>
setPc(address+pc); </td>
<td>
- Fix!
+
</td>
</tr>
@@ -776,7 +787,7 @@ int address = pop();<br>
</td>
<td>
pushIntStack((popIntStack() == popIntStack()) ? 1 : 0); <td>
- Fix!
+
</td>
</tr>
<tr>
@@ -788,7 +799,7 @@ int address = pop();<br>
</td>
<td>
pushIntStack((popIntStack() != popIntStack()) ? 1 : 0); <td>
- Fix!
+
</td>
</tr>
<tr>
@@ -800,7 +811,7 @@ int address = pop();<br>
</td>
<td>
pushIntStack(-popIntStack());<td>
- Fix!
+
</td>
</tr>
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