Improve initialization sequence documentation

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Virgil Dupras 2020-11-28 11:17:50 -05:00
parent f8b7a3ce65
commit b48455e4db

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@ -127,13 +127,13 @@ offsets, but thankfully, there aren't many system variables.
Here's a list of them: Here's a list of them:
SYSVARS FUTURE USES +3c BLK(* SYSVARS FUTURE USES +3c BLK(*
+02 CURRENT +3e A@* +02 CURRENT +3e A@ ialias
+04 HERE +40 A!* +04 HERE +40 A! ialias
+06 C<? +42 A,* +06 C<? +42 A, ialias
+08 C<* override +44 FUTURE USES +08 C<* override +44 FUTURE USES
+0a NLPTR +51 CURRENTPTR +0a NL ialias +51 CURRENTPTR
+0c C<* +53 (emit) override +0c C<* +53 EMIT ialias
+0e WORDBUF +55 (key) override +0e WORDBUF +55 KEY ialias
+2e BOOT C< PTR +57 FUTURE USES +2e BOOT C< PTR +57 FUTURE USES
+30 IN> +30 IN>
+32 IN(* +70 DRIVERS +32 IN(* +70 DRIVERS
@ -186,8 +186,17 @@ very few things.
In a normal system, BOOT is in core words at B396 and does a In a normal system, BOOT is in core words at B396 and does a
few things: few things:
1. Initialize all overrides to 0. 1. Initialize a few core variables:
2. Write LATEST in BOOT C< PTR ( see below ). CURRENT* -> CURRENT (RAM+02)
BOOT C< PTR -> LATEST
C<* override -> 0
2. Initialized ialiases in this way:
EMIT -> (emit)
KEY -> (key)
NL -> CRLF
A@ -> C@
A! -> C!
A, -> C,
3. Set "C<*", the word that C< calls, to (boot<). 3. Set "C<*", the word that C< calls, to (boot<).
4. Call INTERPRET which interprets boot source code until 4. Call INTERPRET which interprets boot source code until
ASCII EOT (4) is met. This usually initializes drivers. ASCII EOT (4) is met. This usually initializes drivers.
@ -196,6 +205,10 @@ few things:
6. (main) interprets from rdln input (usually from KEY) until 6. (main) interprets from rdln input (usually from KEY) until
EOT is met, then calls BYE. EOT is met, then calls BYE.
If, for some reason, you need to override an ialias at some
point, you de-override it by re-setting it to the address of
the word specified at step 2.
# Stable ABI # Stable ABI
The Stable ABI lives at the beginning of the binary and prov- The Stable ABI lives at the beginning of the binary and prov-