Add external ram save capabilities

readme.md

@@ -47,6 +47,18 @@ Available actions:
 
 You can change the password from the settings menu (Accessed using [mode]), and pressing the [sto->] button. This will prompt for a new password which will be automatically saved.
 
+### External Backup
+Cesium also offers the ability to externally back up the RAM from within the OS. These are also tied to the shortcuts:
+
+**PLEASE DO NOT USE THESE FOR TRIVIAL ISSUES. THEY MAY CAUSE UNINTENDED WEAR ON THE FLASH CHIP, SO BE SURE TO MODERATE USEAGE.**
+**THE FLASH CHIP IS ONLY DESIGNED TO SUPPORT 100,000+ ERASE CYCLES**
+
+| Combination | Action                                                     |
+|-------------|------------------------------------------------------------|
+| [on]+[8]    | Backup RAM from TI-OS                                      |
+| [on]+[5]    | Remove latest RAM backup                                   |
+| [on]+[2]    | Restore RAM from latest backup                             |
+
 ### Running Programs
 Cesium can run programs written in ASM, C, ICE, or BASIC, either from the archive or not. It is prefered that you place programs in the archive, as it will protect them against RAM clears.
 To run a program, simply press [2ND] or [Enter]. After a program is finished running, it will return to Cesium.

src/routines/hooks.asm

@@ -95,6 +95,12 @@ GetKeyHook:
 	jr	z,Good
 	cp	a,skStat
 	jr	z,Good
+	cp	a,sk8
+	jr	z,Good
+	cp	a,sk5
+	jr	z,Good
+	cp	a,sk2
+	jr	z,Good
 	ret
 
 Good:
@@ -105,22 +111,140 @@ Good:
 	bit	0,(hl)
 	jr	z,NoOnKey
 	cp	a,skPrgm
-	jr	z,StartCesium
+	jr	z,RelocateHook
 	cp	a,skStat
-	jr	z,StartPassword
-	cp	a,skEnter
-	jr	z,LaunchProgram
+	jr	z,RelocateHook
+	cp	a,sk8
+	jr	z,RelocateHook
+	cp	a,sk5
+	jr	z,RelocateHook
+	cp	a,sk2
+	jr	z,RelocateHook
 	ret
 
 NoOnKey:
 	dec	a
 	inc	a
 	ret
 
-LaunchProgram:
-	ld	hl,progCurrent
-	call	_Mov9ToOP1
-	jr	NoOnKey
+RelocateHook:
+	push	af
+	ld	a,$E1
+	ld	($E30800),a
+	ld	a,$E9
+	ld	($E30801),a
+	pop	af
+	ld	bc,HookEnd-HookStart
+	ld	de,Hook
+	push	bc
+	call	$E30800
+	ld	bc,12
+	add	hl,bc
+	pop	bc
+	ldir
+	jp	Hook
+HookStart:
+relocate(pixelshadow2)
+Hook:
+	cp	a,skPrgm
+	jp	z,StartCesium
+	cp	a,skStat
+	jp	z,StartPassword
+	cp	a,sk8
+	jp	z,BackupRAM
+	cp	a,sk5
+	jp	z,ClearOldRAM
+	cp	a,sk2
+	jp	z,RestoreRAM
+	ret
+
+ClearOldRAM:
+	ld	hl,$D00001
+	xor	a,a
+	ld	(hl),a
+	inc	hl
+	ld	(hl),a
+	ld	a,($3C0000)
+	or	a,a
+	ret	z
+	di
+	ld.sis	sp,$ea1f
+	call.is	unlocks & $ffff
+	ld	b,0
+	ld	de,$3C0000
+	call	_WriteFlashByte
+	call.is	locks & $ffff
+	ret
+
+RestoreRAM:
+	di
+	ld	hl,$3C0001
+	ld	a,$A5
+	cp	a,(hl)
+	ret	nz
+	dec	hl
+	ld	a,$5a
+	cp	a,(hl)
+	ret	nz
+	ld	hl,$D00002
+	ld	a,$A5
+	cp	a,(hl)
+	ret	nz
+	dec	hl
+	cp	a,(hl)
+	ret	nz
+	jp	0
+
+BackupRAM:
+	call	_os_ClearStatusBarLow
+	di
+	ld	de,$e71c
+	ld.sis	(drawFGColor & $ffff),de
+	ld.sis	de,(statusBarBGColor & $ffff)
+	ld.sis	(drawBGColor & $ffff),de
+	ld	a,14
+	ld	(penRow),a
+	ld	de,2
+	ld.sis	(penCol & $ffff), de
+	ld	hl,savingstringhook
+	call	_VPutS
+	di					; let's do some crazy flash things so that way we can save the RAM state...
+	ld.sis	sp,$ea1f
+	call.is	unlocks & $ffff
+	ld	a,$3F
+	call	EraseSectorhook			; clean out the flash sectors
+	ld	a,$3E
+	call	EraseSectorhook
+	ld	a,$3D
+	call	EraseSectorhook
+	ld	a,$3C
+	call	EraseSectorhook			; this is so we can store the new RAM data \o/
+	ld	hl,$D00002
+	ld	(hl),$A5
+	dec	hl
+	ld	(hl),$A5
+	dec	hl
+	ld	(hl),$5A			; write some magical bytes
+	ld	de,$3C0000			; we could just write all of ram
+	ld	bc,$40000
+	call	_WriteFlash
+	call.is	locks & $ffff
+	call	_DrawStatusBar
+	dec	a
+	inc	a
+	ret
+EraseSectorhook:
+	ld	bc,$f8
+	push	bc
+	jp	_EraseFlashSector
+savingstringhook:
+#ifdef ENGLISH
+	.db	"Backing up...",0
+#else
+	.db	"Sauvegarde en cours...",0
+#endif
+
+#include "routines/ramhook.asm"
 
 StartCesium:
 	xor	a,a
@@ -150,31 +274,14 @@ StartCesium:
 	jp	_NewContext
 
 StartPassword:
-	ld	bc,reloacted_code_password_end-reloacted_code_password_start
-	ld	de,pixelshadow2
-	push	bc
-	ld	a,$E1
-	ld	($E30800),a
-	ld	a,$E9
-	ld	($E30801),a
-	call	$E30800
-	ld	bc,12
-	add	hl,bc
-	pop	bc
-	ldir
-	jp	FindSettings
-
-reloacted_code_password_start:
-relocate(pixelshadow2)
-FindSettings:
 	ld	hl,CesiumAppvarNameRelocated
 	call	_Mov9ToOP1
 	call	_ChkFindSym
 	call	_ChkInRam
 	push	af
 	call	z,_Arc_Unarc			; archive it
 	pop	af
-	jr	z,FindSettings			; now lookup the settings appvar
+	jr	z,StartPassword			; now lookup the settings appvar
 	ex	de,hl
 	ld	de,9
 	push	de
@@ -248,4 +355,5 @@ PasswordStrRelocated:
 PasswordTemp:
 	.dl	0
 endrelocate()
-reloacted_code_password_end:
+HookEnd:
+.echo "Hook Size:\t",HookEnd-HookStart

src/routines/loader.asm

@@ -1,5 +1,11 @@
 .assume adl = 1
 
+; inputs:
+;  shortcutKeys - Check if shortcut keys are enabled
+;  prgmNamePtr - Pointer to program name
+;  
+; flags:
+;  bootEnter - Was enter used to launch?
 CesiumLoader:
 	bit	bootEnter,(iy+cesiumFlags)
 	jr	nz,SkipSave
@@ -130,16 +136,13 @@ SaveRAMState:
 	call.is	lock & $ffff
 
 	ret
-   
+
 EraseSector:
 	ld	bc,$0000F8			; apparently we can't erase sectors unless we call this routine from flash... Well, I called it from flash now :) (lol, what a secuity flaw)
 	push	bc
 	jp	_EraseFlashSector
 
-#include "routines/ramsave.asm"
-
 savingstring:
-
 #ifdef ENGLISH
 	.db	"Backing up...",0
 #else
@@ -149,3 +152,5 @@ savingstring:
 StopError:
 	.db "Stop",0
 StopErrorEnd:
+
+#include "routines/ramsave.asm"

src/routines/main.asm

@@ -1,7 +1,7 @@
 CESIUM_OS_BEGIN:
-	cp	a,$aa
+	cp	a,$aa				; executed program reload
 	jr	z,LoadSettings
-	
+
 	xor	a,a
 	sbc	hl,hl
 	ld	(currSelAbs),hl

src/routines/ramhook.asm

@@ -0,0 +1,23 @@
+
+	.assume	adl = 0
+
+unlocks:
+	ld	a, $8c
+	out0	($24), a
+	ld	c, 4
+	in0	a, (6)
+	or	c
+	out0	(6), a
+	out0	($28), c
+	ret.l
+locks:
+	xor	a, a
+	out0	($28), a
+	in0	a, (6)
+	res	2, a
+	out0	(6), a
+	ld	a, $88
+	out0	($24), a
+	ret.l
+
+	.assume adl = 1