diff --git a/bus.cpp b/bus.cpp
index 5d73884..232d82d 100644
--- a/bus.cpp
+++ b/bus.cpp
@@ -120,8 +120,6 @@ bus *bus::deserialize(const json_t *const j, console *const cnsl, std::atomic_ui
 
 void bus::set_memory_size(const int n_pages)
 {
-	this->n_pages = n_pages;
-
 	uint32_t n_bytes = n_pages * 8192l;
 
 	delete m;
@@ -474,7 +472,7 @@ uint16_t bus::read(const uint16_t addr_in, const word_mode_t word_mode, const rm
 		}
 
 		// LO size register field must be all 1s, so subtract 1
-		uint32_t system_size = n_pages * 8192l / 64 - 1;
+		uint32_t system_size = m->get_memory_size() / 64 - 1;
 
 		if (a == ADDR_SYSSIZE + 2) {  // system size HI
 			uint16_t temp = system_size >> 16;
@@ -505,7 +503,7 @@ uint16_t bus::read(const uint16_t addr_in, const word_mode_t word_mode, const rm
 		return 0;
 	}
 
-	if (m_offset >= uint32_t(n_pages * 8192)) {
+	if (m_offset >= m->get_memory_size()) {
 		if (peek_only) {
 			DOLOG(debug, false, "READ from %06o - out of range!", addr_in);
 			return 0;
@@ -696,8 +694,8 @@ uint32_t bus::calculate_physical_address(const int run_mode, const uint16_t a, c
 				}
 			}
 
-			if (m_offset >= n_pages * 8192l && !is_io) [[unlikely]] {
-				DOLOG(debug, !peek_only, "bus::calculate_physical_address %o >= %o", m_offset, n_pages * 8192l);
+			if (m_offset >= m->get_memory_size() && !is_io) [[unlikely]] {
+				DOLOG(debug, !peek_only, "bus::calculate_physical_address %o >= %o", m_offset, m->get_memory_size());
 				DOLOG(debug, false, "TRAP(04) (throw 6) on address %06o", a);
 
 				if (mmu_->is_locked() == false) {
@@ -1025,7 +1023,7 @@ write_rc_t bus::write(const uint16_t addr_in, const word_mode_t word_mode, uint1
 
 	DOLOG(debug, false, "WRITE to %06o/%07o %c %c: %06o", addr_in, m_offset, space == d_space ? 'D' : 'I', word_mode == wm_byte ? 'B' : 'W', value);
 
-	if (m_offset >= uint32_t(n_pages * 8192)) {
+	if (m_offset >= m->get_memory_size()) {
 		c->trap(004);  // no such RAM
 		throw 1;
 	}
@@ -1042,7 +1040,7 @@ void bus::writePhysical(const uint32_t a, const uint16_t value)
 {
 	DOLOG(debug, false, "physicalWRITE %06o to %o", value, a);
 
-	if (a >= n_pages * 8192l) {
+	if (a >= m->get_memory_size()) {
 		DOLOG(debug, false, "physicalWRITE to %o: trap 004", a);
 		c->trap(004);
 		throw 12;
@@ -1054,7 +1052,7 @@ void bus::writePhysical(const uint32_t a, const uint16_t value)
 
 uint16_t bus::readPhysical(const uint32_t a)
 {
-	if (a >= n_pages * 8192l) {
+	if (a >= m->get_memory_size()) {
 		DOLOG(debug, false, "physicalREAD from %o: trap 004", a);
 		c->trap(004);
 		throw 13;
diff --git a/bus.h b/bus.h
index b0ae4c8..d0fdd6b 100644
--- a/bus.h
+++ b/bus.h
@@ -75,10 +75,7 @@ private:
 	rl02    *rl02_   { nullptr };
 	tty     *tty_    { nullptr };
 	kw11_l  *kw11_l_ { nullptr };
-
 	mmu     *mmu_    { nullptr };
-
-	int      n_pages { DEFAULT_N_PAGES };
 	memory  *m       { nullptr };
 
 	uint16_t microprogram_break_register { 0 };
@@ -104,7 +101,6 @@ public:
 	void set_debug_mode() { console_switches |= 128; }
 	uint16_t get_console_leds() { return console_leds; }
 
-	int  get_memory_size() const { return n_pages; }
 	void set_memory_size(const int n_pages);
 
 	void mmudebug(const uint16_t a);
diff --git a/debugger.cpp b/debugger.cpp
index 30da333..189d17f 100644
--- a/debugger.cpp
+++ b/debugger.cpp
@@ -27,6 +27,7 @@
 #include "disk_backend_nbd.h"
 #include "loaders.h"
 #include "log.h"
+#include "memory.h"
 #include "tty.h"
 #include "utils.h"
 
@@ -1018,7 +1019,7 @@ void debugger(console *const cnsl, bus *const b, std::atomic_uint32_t *const sto
 				if (parts.size() == 2)
 					b->set_memory_size(std::stoi(parts.at(1)));
 				else {
-					int n_pages = b->get_memory_size();
+					int n_pages = b->getRAM()->get_memory_size();
 
 					cnsl->put_string_lf(format("Memory size: %u pages or %u kB (decimal)", n_pages, n_pages * 8192 / 1024));
 				}
diff --git a/memory.h b/memory.h
index 1a5dcbc..8ec1c14 100644
--- a/memory.h
+++ b/memory.h
@@ -18,6 +18,8 @@ public:
 	memory(const uint32_t size);
 	~memory();
 
+	uint32_t get_memory_size() const { return size; }
+
 	void reset();
 #if IS_POSIX
 	json_t *serialize() const;