diff --git a/scsp.h b/scsp.h
index 208cc0c..4a9df32 100644
--- a/scsp.h
+++ b/scsp.h
@@ -90,7 +90,7 @@ typedef struct scsp_ctrl {
 
 static_assert((sizeof (struct scsp_ctrl)) == 0x30);
 static_assert((offsetof (struct scsp_ctrl, STATUS)) == 0x08);
-static_assert((offsetof (struct scsp_ctrl, DMEA)) == 0x12);
+static_assert((offsetof (struct scsp_ctrl, DMAL)) == 0x12);
 static_assert((offsetof (struct scsp_ctrl, MCIRE)) == 0x2e);
 
 typedef struct scsp_dsp_lh {
@@ -154,6 +154,7 @@ extern struct scsp scsp __asm("scsp");
 static_assert((sizeof (struct scsp)) == 0x100ee4);
 static_assert((offsetof (struct scsp, ram)) == 0x000000);
 static_assert((offsetof (struct scsp, reg)) == 0x100000);
+static_assert((sizeof (scsp.reg.dsp.STEP)) == 0x400);
 
 // bits
 
@@ -247,7 +248,7 @@ enum mixer_bits {
 #define PITCH__FNS(n) (((n) & 0x3ff) << 0 )
 //};
 
-enum master_bits {
+enum scsp_bits {
   MIXER__MEM4MB = (1 << 9),
   MIXER__DAC18B = (1 << 8),
 #define MIXER__MVOL(n) ((n) << 0)
diff --git a/scu.h b/scu.h
index 1bd78bb..e426ccc 100644
--- a/scu.h
+++ b/scu.h
@@ -58,6 +58,7 @@ typedef struct scu_reg {
 static_assert((sizeof (struct scu_reg)) == 0xD0);
 static_assert((offsetof (struct scu_reg, D1R)) == 0x20);
 static_assert((offsetof (struct scu_reg, AIACK)) == 0xA8);
+static_assert((offsetof (struct scu_reg, AREF)) == 0xB8);
 
 struct scu {
   scu_reg reg;
diff --git a/sh2.lds b/sh2.lds
index 81c7085..306ba56 100644
--- a/sh2.lds
+++ b/sh2.lds
@@ -2,6 +2,7 @@ OUTPUT_FORMAT("elf32-sh", "elf32-sh", "elf32-sh")
 OUTPUT_ARCH(sh)
 MEMORY
 {
+  ipl_rom : ORIGIN = 0x00000000, LENGTH = 512K
   work_ram_l : ORIGIN = 0x00200000, LENGTH = 1M
   work_ram_h : ORIGIN = 0x06000000, LENGTH = 1M
 }
@@ -44,3 +45,6 @@ vdp2 = 0x25E00000;
 scu  = 0x25FE0000;
 sh2_vec = 0x06000000;
 sh2  = 0xfffffe00;
+
+work_ram_l = 0x20200000;
+work_ram_h = 0x26000000;
diff --git a/smpc.h b/smpc.h
index 694f8d2..df15caf 100644
--- a/smpc.h
+++ b/smpc.h
@@ -206,6 +206,8 @@ static_assert((sizeof (smpc_reg)) == 0x80);
 static_assert((offsetof (struct smpc_reg, oreg.OREG0)) == 0x21);
 static_assert((offsetof (struct smpc_reg, oreg.OREG1)) == 0x23);
 static_assert((offsetof (struct smpc_reg, oreg.OREG31)) == 0x5f);
+static_assert((offsetof (struct smpc_reg, COMREG)) == 0x1f);
+static_assert((offsetof (struct smpc_reg, SR)) == 0x61);
 static_assert((offsetof (struct smpc_reg, SF)) == 0x63);
 
 struct smpc {