From 10864afa96f502da9cd89c2e62505a69061b4e0e Mon Sep 17 00:00:00 2001
From: Virgil Dupras <hsoft@hardcoded.net>
Date: Sun, 1 Dec 2019 20:11:13 -0500
Subject: [PATCH] recipes/ti84: use the BASIC shell

---
 apps/shell/README.md          |  4 ++++
 doc/README.md                 |  1 +
 recipes/rc2014/basic/glue.asm |  1 +
 recipes/ti84/README.md        | 14 +++++++++++--
 recipes/ti84/glue.asm         | 39 ++++++++++++++++++++++++-----------
 5 files changed, 45 insertions(+), 14 deletions(-)

diff --git a/apps/shell/README.md b/apps/shell/README.md
index 990a032..3cf6b07 100644
--- a/apps/shell/README.md
+++ b/apps/shell/README.md
@@ -1,5 +1,9 @@
 # shell
 
+**This shell is currently being replaced with the
+[BASIC shell](../basic/README.md). While it's still used in many places, it's
+being phased out.**
+
 The shell is a text interface giving you access to commands to control your
 machine. It is not built to be user friendly, but to minimize binary space and
 maximize code simplicity.
diff --git a/doc/README.md b/doc/README.md
index 9bbd03f..01aa08d 100644
--- a/doc/README.md
+++ b/doc/README.md
@@ -8,6 +8,7 @@
 ## User guide
 
 * [The shell](../apps/shell/README.md)
+* [The BASIC shell](../apps/basic/README.md)
 * [Load code in RAM and run it](load-run-code.md)
 * [Using block devices](blockdev.md)
 * [Using the filesystem](fs.md)
diff --git a/recipes/rc2014/basic/glue.asm b/recipes/rc2014/basic/glue.asm
index 0c10a01..edf417b 100644
--- a/recipes/rc2014/basic/glue.asm
+++ b/recipes/rc2014/basic/glue.asm
@@ -51,6 +51,7 @@ init:
 
 	call	aciaInit
 	ei
+	call	basInit
 	jp	basStart
 
 
diff --git a/recipes/ti84/README.md b/recipes/ti84/README.md
index b533744..3f58001 100644
--- a/recipes/ti84/README.md
+++ b/recipes/ti84/README.md
@@ -10,7 +10,7 @@ There is, however, a built-in USB controller that might prove very handy.
 
 ## Recipe
 
-This recipe gets the Collapse OS shell to run on the TI-84+, using its LCD
+This recipe gets the Collapse OS BASIC shell to run on the TI-84+, using its LCD
 screen as output and its builtin keyboard as input.
 
 ## Gathering parts
@@ -66,9 +66,19 @@ Press "1" to continue.
 
 When this is done, you can press the ON button to see Collapse OS' prompt!
 
+## Validation errors
+
+Sometimes, when uploading an upgrade file to your calculator, you'll get a
+validation error. You can always try again, but in my own experience, some
+specific binaries will simply always be refused by the calculator. Adding
+random `nop` or reordering lines (when it makes sense, of course) should fix
+the problem.
+
+I'm not sure whether it's a bug with the calculator or with `mktiupgrade`.
+
 ## Usage
 
-The shell works like a normal shell, but with very tight screen space.
+The shell works like a normal BASIC shell, but with very tight screen space.
 
 When pressing a "normal" key, it spits the symbol associated to it depending
 on the current mode. In normal mode, it spits the digit/symbol. In Alpha mode,
diff --git a/recipes/ti84/glue.asm b/recipes/ti84/glue.asm
index 2f91c1d..e636473 100644
--- a/recipes/ti84/glue.asm
+++ b/recipes/ti84/glue.asm
@@ -37,19 +37,31 @@
 .equ	STDIO_PUTC	lcdPutC
 .inc "stdio.asm"
 
-; *** Shell ***
-.inc "lib/util.asm"
-.inc "lib/parse.asm"
-.inc "lib/args.asm"
-.inc "lib/stdio.asm"
-.equ	SHELL_RAMSTART	STDIO_RAMEND
-.equ	SHELL_EXTRA_CMD_COUNT 0
-.inc "shell/main.asm"
+; *** BASIC ***
 
+; RAM space used in different routines for short term processing.
+.equ	SCRATCHPAD_SIZE	0x20
+.equ	SCRATCHPAD	STDIO_RAMEND
+.inc "lib/util.asm"
+.inc "lib/ari.asm"
+.inc "lib/parse.asm"
+.inc "lib/fmt.asm"
+.equ	EXPR_PARSE	parseLiteralOrVar
+.inc "lib/expr.asm"
+.inc "basic/util.asm"
+.inc "basic/parse.asm"
+.inc "basic/tok.asm"
+.equ	VAR_RAMSTART	SCRATCHPAD+SCRATCHPAD_SIZE
+.inc "basic/var.asm"
+.equ	BUF_RAMSTART	VAR_RAMEND
+.inc "basic/buf.asm"
+.equ	BAS_RAMSTART	BUF_RAMEND
+.inc "basic/main.asm"
+
+.out BAS_RAMEND
 boot:
 	di
-	ld	hl, RAMEND
-	ld	sp, hl
+	ld	sp, RAMEND
 	im	1
 
 	; enable ON key interrupt
@@ -67,12 +79,15 @@ boot:
 	halt
 
 main:
+	; Fun fact: if I place this line just above basStart like I would
+	; normally do, my TI-84+ refuses to validate the binary. But placed
+	; here, validation works fine.
+	call	basInit
 	call	kbdInit
 	call	lcdInit
 	xor	a
 	call	lcdSetCol
-	call	shellInit
-	jp	shellLoop
+	jp	basStart
 
 handleInterrupt:
 	di