diff --git a/.debugusrc1.js b/.debugusrc1.js
index 04b2b37..90e6e68 100644
--- a/.debugusrc1.js
+++ b/.debugusrc1.js
@@ -11,5 +11,13 @@ print_pid();
 print_program_load_offset();
 mk_brk_addr(main_offset);
 list_brks();
+log_inf("1 --------------------------------------------");
+dump_regs();
+var r14 = get_reg("r14");
+set_reg("r14", "0x0");
+log_inf("2 --------------------------------------------");
+dump_regs();
+set_reg("r14", r14);
+log_inf("3 --------------------------------------------");
 dump_regs();
 cont();
diff --git a/debugus.c b/debugus.c
index 89ac129..8b35a9e 100644
--- a/debugus.c
+++ b/debugus.c
@@ -202,7 +202,7 @@ void dbg_js_mk_brk_addr(js_State *js)
     Dbg *dbg = getdbg();
     const char *addr_str = js_tostring(js, 1);
     uintptr_t addr;
-    sscanf(addr_str, "%"SCNxPTR, &addr);
+    sscanf(addr_str, "0x%"SCNxPTR, &addr);
     Brk brk = { .pid = dbg->pid, .addr = dbg->program_load_offset + addr };
     brk_enable(&brk);
     hashtable_set(&dbg->brks, addr_str, &brk, sizeof(brk));
@@ -230,7 +230,7 @@ void dbg_js_set_program_load_offset(js_State *js)
     Dbg *dbg = getdbg();
     const char *addr_str = js_tostring(js, 1);
     uintptr_t addr;
-    sscanf(addr_str, "%"SCNxPTR, &addr);
+    sscanf(addr_str, "0x%"SCNxPTR, &addr);
     dbg->program_load_offset = addr;
 
     js_pushundefined(js);
@@ -304,6 +304,18 @@ void dbg_js_get_reg(js_State *js)
     js_pushstring(js, buf);
 }
 
+void dbg_js_set_reg(js_State *js)
+{
+    Dbg *dbg = getdbg();
+    const char *name = js_tostring(js, 1);
+    Register r = get_reg_from_name(name);
+    const char *value_str = js_tostring(js, 2);
+    uint64_t value;
+    sscanf(value_str, "0x%"SCNx64, &value);
+    set_reg_value(dbg->pid, r, value);
+    js_pushundefined(js);
+}
+
 void dbg_init_js(Dbg *dbg)
 {
     dbg->js   = js_newstate(NULL, NULL, JS_STRICT);
@@ -325,7 +337,8 @@ void dbg_init_js(Dbg *dbg)
     make_js_func(get_file, 0);
     make_js_func(get_pid, 0);
     make_js_func(get_program_load_offset, 0);
-    make_js_func(get_reg, 1);
+    make_js_func(get_reg, 1 /*reg name*/);
+    make_js_func(set_reg, 2 /* reg name, value*/);
 
     #undef make_js_func
 }