diff --git a/Makefile b/Makefile
index a9cff11..a52fc4c 100644
--- a/Makefile
+++ b/Makefile
@@ -9,10 +9,13 @@ METAL_RELFILES      := $(METAL_ASM_SRCFILES:%.asm=$(BUILDDIR)/metal/%.rel) \
 METAL_CC            := sdcc
 METAL_AS            := sdasz80
 METAL_MAKEBIN       := makebin
-METAL_FLAGS         := -mz80 --no-std-crt0 --code-loc 0x0080 --data-loc 0x8000
+METAL_FLAGS         := -mz80 --no-std-crt0 --code-loc 0xC080 --code-size 0x2F80 --data-loc 0xF000
 METAL_CPPFLAGS      := -I src -I $(BUILDDIR)/metal/generated --disable-warning 283
 METAL_BIN_SIZE      := 32768
-METAL_RAM_SIZE      := 32768
+METAL_RAM_SIZE      := 16384
+METAL_IMAGE_SIZE    := 65536
+MONITOR_BASE        := 0xC000
+MONITOR_ROM_OFFSET  := 128
 
 .DEFAULT_GOAL       := metal
 
@@ -21,24 +24,34 @@ METAL_RAM_SIZE      := 32768
 all: metal
 
 metal: $(BUILDDIR)/metal/$(TARGET).ihx $(BUILDDIR)/metal/$(TARGET).bin $(BUILDDIR)/metal/$(TARGET).prog.bin
-	@awk -v rom_capacity=$(METAL_BIN_SIZE) -v ram_capacity=$(METAL_RAM_SIZE) '\
-		$$1 ~ /^_(CODE|HOME|GSINIT|GSFINAL|INITIALIZER|ITABLE[0-7]*)$$/ { rom += $$5 } \
-		$$1 ~ /^_(DATA|INITIALIZED|BSEG|BSS|HEAP|STACK)$$/ { ram += $$5 } \
+	@stored=$$(wc -c < $(BUILDDIR)/metal/$(TARGET).prog.bin); \
+	awk -v rom_capacity=$(METAL_BIN_SIZE) -v stored=$$stored -v ram_capacity=$(METAL_RAM_SIZE) '\
+		$$1 ~ /^_(CODE|HOME|GSINIT|GSFINAL|INITIALIZER)$$/ || $$1 ~ /^_ITABLE/ { code += $$5 } \
+		$$1 ~ /^_(DATA|INITIALIZED|BSEG|BSS|HEAP)$$/ { data += $$5 } \
 		END { \
 			printf "\nMemory usage:\n"; \
-			printf "  ROM: %5u / %5u bytes (%5.1f%%), %5u bytes free\n", rom, rom_capacity, 100 * rom / rom_capacity, rom_capacity - rom; \
-			printf "  RAM: %5u / %5u bytes (%5.1f%%), %5u bytes free\n", ram, ram_capacity, 100 * ram / ram_capacity, ram_capacity - ram; \
+			printf "  ROM storage:  %5u / %5u bytes (%5.1f%%)\n", stored, rom_capacity, 100 * stored / rom_capacity; \
+			printf "  Runtime RAM:  %5u / %5u bytes (%5.1f%%), %5u bytes for growth/stack\n", code + data, ram_capacity, 100 * (code + data) / ram_capacity, ram_capacity - code - data; \
+			printf "    code/vector: %5u bytes; static data: %5u bytes\n", code, data; \
 		}' $(BUILDDIR)/metal/$(TARGET).map
 
 $(BUILDDIR)/metal/$(TARGET).ihx: $(METAL_RELFILES)
 	@mkdir -p $(@D)
 	$(METAL_CC) $(METAL_FLAGS) -o $@ $(METAL_RELFILES)
 
-$(BUILDDIR)/metal/$(TARGET).bin: $(BUILDDIR)/metal/$(TARGET).ihx
-	$(METAL_MAKEBIN) -s $(METAL_BIN_SIZE) $< $@
+$(BUILDDIR)/metal/$(TARGET).flat.bin: $(BUILDDIR)/metal/$(TARGET).ihx
+	$(METAL_MAKEBIN) -s $(METAL_IMAGE_SIZE) $< $@
 
-$(BUILDDIR)/metal/$(TARGET).prog.bin: $(BUILDDIR)/metal/$(TARGET).ihx
-	$(METAL_MAKEBIN) -p $< $@
+$(BUILDDIR)/metal/$(TARGET).prog.bin: $(BUILDDIR)/metal/$(TARGET).flat.bin
+	@payload_end=$$(awk '$$1 == "DEF" && $$2 == "monitor_image_end" { print $$3 }' $(BUILDDIR)/metal/$(TARGET).noi); \
+	payload_size=$$((payload_end - $(MONITOR_BASE))); \
+	test $$payload_size -gt 0; \
+	dd if=$< of=$@ bs=1 count=$(MONITOR_ROM_OFFSET) status=none; \
+	dd if=$< of=$@ bs=1 skip=$$(( $(MONITOR_BASE) )) seek=$(MONITOR_ROM_OFFSET) count=$$payload_size conv=notrunc status=none
+
+$(BUILDDIR)/metal/$(TARGET).bin: $(BUILDDIR)/metal/$(TARGET).flat.bin $(BUILDDIR)/metal/$(TARGET).prog.bin
+	dd if=$< of=$@ bs=$(METAL_BIN_SIZE) count=1 status=none
+	dd if=$(BUILDDIR)/metal/$(TARGET).prog.bin of=$@ conv=notrunc status=none
 
 $(BUILDDIR)/metal/%.rel: %.c
 	@mkdir -p $(@D)
diff --git a/README.md b/README.md
index 7f997c2..1a4e992 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,14 @@
 # Z80 UART monitor
 
 This ROM provides a small interactive monitor on the UART/CTC card at I/O base
-`20`. Connect a terminal at **2400 baud, 8 data bits, no parity, 1 stop bit**.
+`20`. At reset, a small ROM bootstrap copies the monitor into the top 16 KiB of
+RAM at `C000-FFFF` and starts it there. Only the occupied vector/code bytes are
+stored and copied; uninitialized data is cleared directly in high RAM. The low ROM can subsequently be disabled
+without taking the monitor, its data, or its interrupt table away. Runtime code
+and vectors occupy the lower part of this window, globals begin at `F000`, and
+the stack grows downward from `FFFF`; no RAM below `C000` is used.
+
+Connect a terminal at **2400 baud, 8 data bits, no parity, 1 stop bit**.
 Commands are case-insensitive and all numeric arguments are hexadecimal; an
 optional `0x` prefix is accepted.
 
@@ -26,4 +33,12 @@ make
 ```
 
 The outputs are `build/metal/monitor.bin` (32 KiB ROM image) and
-`build/metal/monitor.prog.bin` (compact programmer image).
+`build/metal/monitor.prog.bin` (compact programmer image). The ROM layout is:
+
+- `0000-007F`: reset/copy bootstrap
+- `0080...`: compact vector/code image copied to RAM starting at `C000`
+- Remaining bytes: unused and available for additional ROM content
+
+The monitor executable starts at `C080`; its IM 2 vector table is at `C040`.
+`monitor.prog.bin` ends immediately after the occupied payload, while
+`monitor.bin` remains a complete 32 KiB chip image.
diff --git a/boot.asm b/boot.asm
index dd77427..5b9b665 100644
--- a/boot.asm
+++ b/boot.asm
@@ -1,5 +1,7 @@
 STACK_TOP = 0xFFFF
 DELAY_LOOPS_PER_MS = 40
+MONITOR_BASE = 0xC000
+MONITOR_ROM_SOURCE = 0x0080
 
         .globl _main
         .globl _delay_ms
@@ -8,33 +10,49 @@ DELAY_LOOPS_PER_MS = 40
         .globl _enable_interrupts
         .globl _disable_interrupts
         .globl _jump_to
+        .globl monitor_image_end
         .globl s__DATA
         .globl l__DATA
         .globl s__INITIALIZER
         .globl s__INITIALIZED
         .globl l__INITIALIZER
 
-.area _ITABLE (ABS)
+.area _BOOT (ABS)
 
 .org 0x00
-        jp init
+        jp boot_copy
 .org 0x08
+boot_copy:
+        di
+        ld sp, #STACK_TOP
+        ld hl, #MONITOR_ROM_SOURCE
+        ld de, #MONITOR_BASE
+        ld bc, #(monitor_image_end - MONITOR_BASE)
+        ldir
+        jp init
+
+.area _ITABLE (ABS)
+
+; The executable vector page is part of the image copied to high RAM.
+.org MONITOR_BASE
+        jp init
+.org MONITOR_BASE + 0x08
         reti
-.org 0x10
+.org MONITOR_BASE + 0x10
         reti
-.org 0x18
+.org MONITOR_BASE + 0x18
         reti
-.org 0x20
+.org MONITOR_BASE + 0x20
         reti
-.org 0x28
+.org MONITOR_BASE + 0x28
         reti
-.org 0x30
+.org MONITOR_BASE + 0x30
         reti
-.org 0x38
+.org MONITOR_BASE + 0x38
         reti
 
-; ITABLE
-.org 0x40
+; IM 2 table: the CTC supplies vectors 40, 42, 44, and 46.
+.org MONITOR_BASE + 0x40
         .dw ctc_isr          ; CTC channel 0: vector 0x40
         .dw ctc_isr          ; CTC channel 1: vector 0x42
         .dw ctc_isr          ; CTC channel 2: vector 0x44
@@ -48,7 +66,7 @@ init:
         call gsinit
 
         ; Setup interrupt mode 2
-        xor a
+        ld a, #0xC0
         ld i, a
         im 2
         call _main
@@ -88,6 +106,7 @@ clear_loop:
 gsinit_done:
 .area _GSFINAL
         ret
+monitor_image_end:
 
 .area _CODE