Added some PDP-10/MACRO-10 blog updates

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Jeff 2017-03-24 16:23:27 -07:00 committed by Jeff Parsons
commit dd24f4bb61
5 changed files with 188 additions and 12 deletions

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@ -1,7 +1,7 @@
---
layout: post
title: The MACRO-10 Assembler, 50 Years Later
date: 2017-02-28 22:00:00
date: 2017-03-21 22:00:00
permalink: /blog/2017/03/21/
machines:
- id: testka10
@ -53,7 +53,7 @@ The above machine uses the Debugger's assemble ('a') command to assemble DEC's "
a 30724 /apps/pdp10/diags/klad/dakaa/MYDAKAA.MAC
The Debugger invokes the MACRO-10 mini-assembler whenever the argument following the target address appears to be a URL.
The Debugger invokes the MACRO-10 mini-assembler whenever the target address is followed by an argument ending with ".MAC".
As previously described in the section on [PDPjs PDP-10 Opcode Tests](/apps/pdp10/tests/opcodes/), the Debugger already
allowed you to assemble instructions directly into memory (eg, `a 100 hrli 1,111111`). This "immediate mode" feature is provided
@ -73,7 +73,7 @@ This command differs from MACRO-10, which uses the `RADIX` pseudo-op to change t
Obviously, it would be nice if both the Debugger and the MACRO-10 mini-assembler used matching commands, but the PCjs debuggers
were written before MACRO-10 support was a consideration, so for now, that's life.
All of the MACRO-10-style base prefixes are supported (^D for decimal, ^B for binary, an ^O for octal):
All of the MACRO-10-style base prefixes are supported (**^D** for decimal, **^B** for binary, an **^O** for octal):
>> print ^D27
0o000000000033 27.
@ -89,7 +89,7 @@ Expressions using angle brackets, another MACRO-10 convention, is also supported
>> print ^D<45-22>
0o000000000027 23.
Note that the base modifier (^D) applies to the entire expression. You can also add MACRO-10 suffixes to integers:
Note that the base modifier (**^D**) applies to the entire expression. You can also add MACRO-10 suffixes to integers:
K: "kilo-", thousands
M: "mega-", millions
@ -118,8 +118,10 @@ so:
Binary shifting using a **B** suffix is also supported. Note that MACRO-10 binary shifting is a "bit" unusual by today's
standards, because the value after the **B**, *n*, is not a count but rather the desired bit position of the right-most bit of
the original value. Moreover, MACRO-10 considers bit 0 the left-most bit, and bit 35 the right-most bit. Last but not least,
*n* is always interpreted as a decimal value, regardless of the current base (radix). *n* can be converted to a shift count
by calculating (35 - n): if the count is positive, it's a left-shift, and if it's negative, it's a right-shift.
*n* is always interpreted as a decimal value, regardless of the current base (radix).
*n* can be converted to a shift count by calculating (35 - n): if the count is positive, it's a left-shift, and if it's negative,
it's a right-shift. Here are some examples:
>> print 1B0
0o400000000000 -34359738368.
@ -140,7 +142,7 @@ by calculating (35 - n): if the count is positive, it's a left-shift, and if it'
0o000000000001 1.
And as the [MACRO-10 Assembler Programmer's Reference Manual (June 1972)](http://archive.pcjs.org/pubs/dec/pdp10/tops10/Macro_Assembler_Reference_Manual-Jun72.pdf),
p. 1-17, points out, all the following expressions are equivalent:
p. 1-17, points out, all of the following "binary shifting" expressions are equivalent:
>> print 10B32
0o000000000100 64. '@'
@ -208,5 +210,80 @@ useful in assembling the following tests:
- [KA10 Basic Instruction Diagnostic #4](/apps/pdp10/diags/klad/dakad/)
- [Assorted MACRO-10 Mini-Assembler Tests](/apps/pdp10/tests/macro10/)
However, there's "*assembling*" and then there's "*assembling correctly*". One early problem I had to immediately
address was the handling of literals. I was originally collecting all the literal (square-bracketed) expressions, like the
**[ZZ]** in the following statement:
MOVE [ZZ] ;MOVE THE CURRENT VALUE OF ZZ INTO E. ZZ IS NON-ZERO
and processing them at the end of the first pass. Well, since ZZ is a symbol that changes repeatedly inside a REPEAT pseudo-op, it
became clear that I needed to process literals immediately. This meant creating a separate assembly scope while processing each
literal; in fact, it meant a stack of scopes, in case literals contained nested literals.
As the [MACRO-10 Assembler Programmer's Reference Manual (April 1978)](http://archive.pcjs.org/pubs/dec/pdp10/tops10/Macro_Assembler_Reference_Manual-Apr78.pdf)
explains:
A literal can include any term, symbol, expression, or statement, but
it must generate at least one but no more than 99 words of data. A
statement that does not generate data (such as a direct-assignment
statement or a RADIX pseudo-op) can be included in a literal, but the
literal must not consist entirely of such statements.
You can nest literals up to 18 levels. You can include any number of
labels in a literal, but a forward reference to a label in a literal
is illegal.
If you use a dot (.) in a literal to retrieve the location counter,
remember that the counter is pointing at the statement containing the
literal, not at the literal itself.
In nested literals, a dot location counter references a statement
outside the outermost literal.
In the sequence:
JRST [HRRZ AC1,V
CAIE AC1,OP
JRST .+1
JRST EVTSTS]
SKIPE C
the expression .+1 generates the address of SKIPE C, not JRST EVTSTS.
Literals having the same value are collapsed in MACRO's literal pool.
Thus for the statements:
PUSH P,[0]
PUSH P,[0]
MOVEI AC1,[ASCIZ /TEST1/]
the same address is shared by the two literals [0], and by the null
word generated at the end of [ASCIZ /TESTI/]. Literal collapsing is
suppressed for those literals that contain errors, undefined expressions,
or EXTERNAL symbols.
Our Mini-Assembler doesn't enforce all the above requirements. It doesn't care if less than 1 or more
than 99 words of data are generated, and it doesn't care if you nest more than 18 levels. It does attempt to honor
MACRO-10's scoping rules for the dot (.) operator, however.
There's also some ambiguity in the above documentation. For example, it says that a literal may contain "any
term, symbol, expression, or statement," but it's not clear if that includes labels.
And when they say that "a forward reference to a label in a literal is illegal," does that only apply to a label
defined *within* the literal, or to *any* forward reference? In other words, which element is illegal in a literal:
the forward reference, or the label?
In any case, our assembler doesn't care, and it's now able to assemble a simple
[Nested Literal Test](/apps/pdp10/tests/macro10/#nested-literal-test) on the
[MACRO-10 Mini-Assembler Tests](/apps/pdp10/tests/macro10/) page.
So, things are improving, but it's still too early expect a lot from the MACRO-10 Mini-Assembler. It currently supports
only a handful of pseudo-ops, and all the code and data it generates is intended for absolute loading only; for now,
it makes no distinction between relocatable and absolute addresses, and the **LOC** and **RELOC** pseudo-ops, like every
other unrecognized or unsupported opcode or pseudo-op, will simply generate an error.
If that sounds like a joke, it's not. This, however, is:
> A man walks into a bar, asks the bartender for a fixup, and the bartender responds, "Absolutely!"
*[@jeffpar](http://twitter.com/jeffpar)*
*Mar 21, 2017*

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@ -0,0 +1,98 @@
---
layout: post
title: Stepping Through PDP-10 Diagnostics
date: 2017-03-24 22:00:00
permalink: /blog/2017/03/24/
machines:
- id: testka10
type: pdp10
config: /devices/pdp10/machine/ka10/test/debugger/machine.xml
debugger: true
commands: a 30724 /apps/pdp10/diags/klad/dakaa/MYDAKAA.MAC
---
Now that the PDPjs MACRO-10 Mini-Assembler is [limping along](/blog/2017/03/21/), it was time to start assembling some
of DEC's PDP-10 diagnostics and loading them into a test machine. The first diagnostic I tried was
[KA10 Basic Instruction Diagnostic #1 (MAINDEC-10-DAKAA-B-D)](/apps/pdp10/diags/klad/dakaa/), which has been loaded into
the machine below.
{% include machine.html id="testka10" %}
Here were the results of my first run attempt:
>> a 30724 /apps/pdp10/diags/klad/dakaa/MYDAKAA.MAC
starting PCjs MACRO-10 Mini-Assembler...
loading MYDAKAA.MAC
CPU will not be auto-started (click Run to start)
2844 words loaded at 030724-036357
00=000000000000 01=000000000000 02=000000000000 03=000000000000
04=000000000000 05=000000000000 06=000000000000 07=000000000000
10=000000000000 11=000000000000 12=000000000000 13=000000000000
14=000000000000 15=000000000000 16=000000000000 17=000000000000
PC=030724 RA=00000000 EA=000000 C0=0 C1=0 OV=0 ND=0 PD=0
030724: 254000 030741 JRST 30741
>> g
running
undefined opcode: 000000
stopped (1698 instructions, 1697 cycles, 14 ms, 121214 hz)
00=000000000000 01=000000000000 02=777777777777 03=000000000000
04=777777777777 05=000000000000 06=000000000000 07=777777777777
10=777777777777 11=000000000000 12=000000000000 13=000000000000
14=000000000000 15=000000000000 16=000000000000 17=000000000000
PC=035057 RA=00000000 EA=000000 C0=0 C1=0 OV=0 ND=0 PD=0
035057: 000000 000000 UUO 0,0
>> dh
035044: 444000 036353 EQV 0,36353 ;history=10
035045: 332000 000000 SKIPE 0,0 ;history=9
035047: 324000 035050 JUMPA 0,35050 ;history=8
035050: 200000 036354 MOVE 0,36354 ;history=7
035051: 404000 036355 AND 0,36355 ;history=6
035052: 444000 036356 EQV 0,36356 ;history=5
035053: 444000 036357 EQV 0,36357 ;history=4
035054: 332000 000000 SKIPE 0,0 ;history=3
035056: 324000 035057 JUMPA 0,35057 ;history=2
035057: 000000 000000 UUO 0,0 ;history=1
Happily, this was a good outcome, because 035057 is the end of the test. If you look at the diagnostic's
[listing file](/apps/pdp10/diags/klad/dakaa/DAKAA.LST.txt), this is what you would normally see at address 035057:
035057 254 00 0 00 030057 ENDXX: JRST BEGEND ;LOOP PROGRAM
Next, I tried [KA10 Basic Instruction Diagnostic #4 (MAINDEC-10-DAKAD-B-D)](/apps/pdp10/diags/klad/dakad/):
>> a 30724 /apps/pdp10/diags/klad/dakad/MYDAKAD.MAC
starting PCjs MACRO-10 Mini-Assembler...
loading MYDAKAD.MAC
1986 words loaded at 030724-034625
00=000000000000 01=000000000000 02=777777777777 03=000000000000
04=777777777777 05=000000000000 06=000000000000 07=777777777777
10=777777777777 11=000000000000 12=000000000000 13=000000000000
14=000000000000 15=000000000000 16=000000000000 17=000000000000
PC=030724 RA=00000000 EA=000000 C0=0 C1=0 OV=0 ND=0 PD=0
030724: 254000 030741 JRST 30741
>> g
running
stopped (450 instructions, 449 cycles, 8 ms, 56125 hz)
00=000000000017 01=400000000000 02=000000000001 03=400000000000
04=000004000004 05=000005000005 06=000006000006 07=000007000007
10=000010000010 11=000011000011 12=000012000012 13=000013000013
14=000014000014 15=000015000015 16=000016000016 17=000017000017
PC=032007 RA=00032007 EA=032007 C0=0 C1=0 OV=0 ND=0 PD=0
032007: 324000 032010 JUMPA 0,32010
>> dh
031774: 201100 000001 MOVEI 2,1 ;history=10
031775: 200142 000000 MOVE 3,0(2) ;history=9
031776: 312140 034461 CAME 3,34461 ;history=8
032000: 324000 032001 JUMPA 0,32001 ;history=7
032001: 476000 000003 SETOM 0,3 ;history=6
032002: 205040 400000 MOVSI 1,400000 ;history=5
032003: 201100 000001 MOVEI 2,1 ;history=4
032004: 200142 000000 MOVE 3,0(2) ;history=3
032005: 312140 034462 CAME 3,34462 ;history=2
032006: 254200 032007 HALT 32007 ;history=1
This looked less good.
*[@jeffpar](http://twitter.com/jeffpar)*
*Mar 24, 2017*

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@ -25,7 +25,7 @@ and pseudo-ops **IRPC**, **IFE**, **IFN**, and **EXP**. It generates 4 words of
{% include machine.html id="testka10" %}
Assemble TEXT.MAC:
Assemble [TEXT.MAC](TEXT.MAC.txt):
a 100 TEXT.MAC
@ -48,7 +48,7 @@ Dump the 4 assembled words with the command `db 100 l4`:
000102: 110111 112113 022 004 111 024 045 ..I.%
000103: 114000 000000 023 000 000 000 000 .....
Source code from TEXT.MAC:
Source code from [TEXT.MAC](TEXT.MAC.txt):
{% highlight text %}
{% include_relative TEXT.MAC.txt %}
@ -56,11 +56,11 @@ Source code from TEXT.MAC:
### Nested Literal Test
Assemble NESTLIT.MAC:
Assemble [NESTLIT.MAC](NESTLIT.MAC.txt):
a 100 NESTLIT.MAC
Source code from NESTLIT.MAC:
Source code from [NESTLIT.MAC](NESTLIT.MAC.txt):
{% highlight text %}
{% include_relative NESTLIT.MAC.txt %}

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@ -1709,6 +1709,7 @@ class DebuggerPDP10 extends Debugger {
*/
if (opCode < 0) {
sOperands = sOpcode + sOperands;
sOpcode = "";
opCode = 0;
}
}

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@ -240,7 +240,7 @@ class Macro10 {
* [4]: operand(s), if any
* [5]: comment, if any
*/
this.reLine = /^\s*([A-Z$%.?][0-9A-Z$%.]*:|)\s*([A-Z$%.][0-9A-Z$%.]*|)(\s*)([^;]+|)(;?[\s\S]*)/i;
this.reLine = /^[ \t]*([A-Z$%.?][0-9A-Z$%.]*:|)[ \t]*([A-Z$%.][0-9A-Z$%.]*|)([ \t]*)([^;]+|)(;?[\s\S]*)/i;
this.macroCall = null; // the active macro being called, if any