rework in CBDOS

src/dos_m65/msg_talk.s

@@ -0,0 +1,52 @@
+
+;
+; Implementation of TALK commands.
+; For detailed description see 'm65dos_bridge.s' file.
+;
+
+
+msg_TALK:
+
+	jsr dos_ENTER
+
+	and #$1F
+	beq msg_TALK_fail        ; branch if device 0 (used to denote lack of device)
+
+	cmp UNIT_SDCARD
+	bne @1
+
+	; TALK on SD card
+
+	lda #$00
+	bra msg_TALK_success
+@1:
+	cmp UNIT_FLOPPY
+	bne @2
+
+	; TALK on floppy
+
+	lda #$01
+	bra msg_TALK_success
+@2:
+	cmp UNIT_RAMDISK
+	bne msg_TALK_fail
+
+	; TALK on ram disk
+
+	lda #$02
+	
+	; FALLTROUGH
+
+msg_TALK_success:
+
+	sta IDX1_TALKER
+	asl
+	sta IDX2_TALKER
+
+	jmp dos_EXIT
+
+msg_TALK_fail:
+
+	lda #K_ERR_DEVICE_NOT_FOUND
+
+	jmp dos_EXIT_A_SEC