diff --git a/src/machine/m_at_t3100e.c b/src/machine/m_at_t3100e.c
index 357f012f2..3c83b0cce 100644
--- a/src/machine/m_at_t3100e.c
+++ b/src/machine/m_at_t3100e.c
@@ -850,6 +850,9 @@ machine_at_t3100e_init(const machine_t *model)
                     NULL, MEM_MAPPING_INTERNAL, &t3100e_ems);
     mem_mapping_disable(&t3100e_ems.upper_mapping);
 
+    if (mem_size < (16384 - 448))
+        mem_set_mem_state_both(mem_size * 1024, 384 * 1024, MEM_READ_INTERNAL | MEM_WRITE_INTERNAL);
+
     device_add(&t3100e_device);
 
     return ret;