From 09cd066256cd607235e8441990ed2b135de3a895 Mon Sep 17 00:00:00 2001
From: FeralChild64 <you@example.com>
Date: Mon, 18 Jan 2021 22:06:22 +0100
Subject: [PATCH] started work on monitor GO/JSR commands

---
 src/kernal/board_m65/mega65_proxies_monitor.s | 16 ++++
 src/mon_m65/bsmon.s                           | 19 +---
 src/mon_m65/imports.s                         |  2 +
 src/mon_m65/mon_command_fill.s                |  2 -
 src/mon_m65/mon_command_jmp_jsr.s             | 93 +++++++++++++++++++
 5 files changed, 113 insertions(+), 19 deletions(-)
 create mode 100644 src/mon_m65/mon_command_jmp_jsr.s

diff --git a/src/kernal/board_m65/mega65_proxies_monitor.s b/src/kernal/board_m65/mega65_proxies_monitor.s
index f16f829c..0a2f9f95 100644
--- a/src/kernal/board_m65/mega65_proxies_monitor.s
+++ b/src/kernal/board_m65/mega65_proxies_monitor.s
@@ -19,6 +19,7 @@ proxy_M1_CHROUT:
 
 	; FALLTROUGH
 
+proxy_M1_jmpout_ret:         ; reused by monitor
 proxy_M1_end:
 
 	jmp map_MON_1
@@ -40,3 +41,18 @@ proxy_M1_memwrite:
 	jsr map_NORMAL
 	sta [Long__TMP], z
 	bra proxy_M1_end
+
+
+; JMP/JSR to user code
+
+proxy_M1_jmpout:
+
+	plz  ; ZR
+	ply  ; YR
+	plx  ; XR
+	pla  ; BP
+	tab
+	pla  ; AC
+	plp  ; SR
+
+	jmp map_NORMAL
diff --git a/src/mon_m65/bsmon.s b/src/mon_m65/bsmon.s
index cfeb070b..966e74c8 100644
--- a/src/mon_m65/bsmon.s
+++ b/src/mon_m65/bsmon.s
@@ -197,9 +197,9 @@ Jump_Table:
          !word Mon_Compare      ; C
          !word Mon_Disassemble  ; D
          !word Mon_Fill         ; F
-         !word Mon_Go           ; G  XXX to be debugged/adapted
+         !word Mon_Go           ; G  XXX to be finished/bugfixed
          !word Mon_Hunt         ; H
-         !word Mon_JSR          ; J  XXX to be debugged/adapted
+         !word Mon_JSR          ; J  XXX to be finished/bugfixed
          !word Mon_Memory       ; M
          !word Mon_Register     ; R
          !word Mon_Transfer     ; T
@@ -400,21 +400,6 @@ Print_Bits:
          PLZ
          RTS
 
-
-; *****
-Mon_Go:
-; *****
-
-         ; XXX to be rewritten for Open ROMs!
-         jmp Main
-
-; ******
-Mon_JSR:
-; ******
-
-         ; XXX to be rewritten for Open ROMs!
-         jmp Main
-
 ; ***********
 Dump_4_Bytes:
 ; ***********
diff --git a/src/mon_m65/imports.s b/src/mon_m65/imports.s
index 07ea79b5..a981faf6 100644
--- a/src/mon_m65/imports.s
+++ b/src/mon_m65/imports.s
@@ -12,6 +12,8 @@
 ;; #ALIAS# monitor_exit                = KERNAL_0.m65_shadow_BZP
 ;; #ALIAS# monitor_memread_helper      = KERNAL_0.proxy_M1_memread
 ;; #ALIAS# monitor_memwrite_helper     = KERNAL_0.proxy_M1_memwrite
+;; #ALIAS# monitor_jmpout              = KERNAL_0.proxy_M1_jmpout
+;; #ALIAS# monitor_jmpout_ret          = KERNAL_0.proxy_M1_jmpout_ret
 
 ;; #ALIAS# CHRIN                       = KERNAL_0.proxy_M1_CHRIN
 ;; #ALIAS# CHROUT                      = KERNAL_0.proxy_M1_CHROUT
diff --git a/src/mon_m65/mon_command_fill.s b/src/mon_m65/mon_command_fill.s
index a872097a..75db2c4f 100644
--- a/src/mon_m65/mon_command_fill.s
+++ b/src/mon_m65/mon_command_fill.s
@@ -2,9 +2,7 @@
 ; Based on BSM (Bit Shifter's Monitor)
 
 
-; *******
 Mon_Fill:
-; *******
 
 	jsr  Get_Param_Range   ; Long_PC = target
 	+bcs Mon_Error         ; Long_CT = count
diff --git a/src/mon_m65/mon_command_jmp_jsr.s b/src/mon_m65/mon_command_jmp_jsr.s
new file mode 100644
index 00000000..573dca3a
--- /dev/null
+++ b/src/mon_m65/mon_command_jmp_jsr.s
@@ -0,0 +1,93 @@
+
+; Based on BSM (Bit Shifter's Monitor)
+
+
+Mon_JSR:
+
+
+	lda  #$00
+	sta  Addr_Mode
+
+	jsr  Get_Val_To_LAC      ; Long_AC = jump address
+	+beq Mon_Error
+
+	; Push return addresses
+
+	lda #>(Mon_JSR_ret-1)    ; XXX return routine should JSR, to store address 
+	pha
+	lda #<(Mon_JSR_ret-1)
+	pha
+
+	lda #>(monitor_jmpout_ret-1)
+	pha
+	lda #<(monitor_jmpout_ret-1)
+	pha
+
+	bra  Mon_Go_JSR_comon
+
+Mon_Go:
+
+	lda  #$00
+	sta  Addr_Mode
+
+	jsr  Get_Val_To_LAC      ; Long_AC = jump address
+	+bne Mon_Go_JSR_comon
+
+	lda  PCL                 ; use PC as jump address
+	sta  Long_AC+0
+	lda  PCH
+	sta  Long_AC+0
+
+	; FALLTROUGH
+
+Mon_Go_JSR_comon:
+
+	lda  Addr_Mode           ; only first 64KB is supported as target
+	+bne Mon_Error
+
+	lda  PCH                 ; push target address for RTS
+	sta  Long_TMP+1
+	lda  PCL
+	sta  Long_TMP+0
+	dew  Long_TMP+0
+
+	lda  Long_TMP+1
+	pha
+	lda  Long_TMP+0
+	pha
+
+	; Prepare registers
+
+	lda  SR
+	pha
+	lda  AC
+	pha
+	lda  BP
+	pha
+	lda  XR
+	pha
+	lda  YR
+	pha
+	lda  ZR
+	pha
+
+	jmp  monitor_jmpout
+
+Mon_JSR_ret:
+
+	; Retrieve registers
+	; XXX address!
+
+	pha
+	php
+	pla
+	sta  SR
+	pla
+	sta  AC
+	tba
+	sta  BP
+	stx  XR
+	sty  YR
+	stz  ZR  
+
+	jmp  Mon_Register