diff --git a/src/rp2_common/pico_crt0/embedded_start_block.inc.S b/src/rp2_common/pico_crt0/embedded_start_block.inc.S
index 4618a3a94..b76b34c79 100644
--- a/src/rp2_common/pico_crt0/embedded_start_block.inc.S
+++ b/src/rp2_common/pico_crt0/embedded_start_block.inc.S
@@ -1,10 +1,12 @@
-#if !defined(PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM)
+// PICO_CONFIG: PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM, Include an image type item in the metadata block, default=0 on RP2040, 1 otherwise, type=bool, group=pico_crt0
+#ifndef PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM
 // todo decide whether we want this item for RP2040 by default, probably not (there are a zilloon binaries out there without it)
 #if !PICO_RP2040
 #define PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM 1
 #endif
 #endif
 
+// PICO_CONFIG: PICO_CRT0_INCLUDE_PICOBIN_VECTOR_TABLE_ITEM, Include a vector table item in the metadata block, default=1 for no_flash binaries, 0 otherwise or on RP2040, type=bool, group=pico_crt0
 #ifndef PICO_CRT0_INCLUDE_PICOBIN_VECTOR_TABLE_ITEM
 // If no_flash bin, then include a vector table item
 #if PICO_NO_FLASH && !PICO_RP2040
@@ -12,6 +14,7 @@
 #endif
 #endif
 
+// PICO_CONFIG: PICO_CRT0_INCLUDE_PICOBIN_ENTRY_POINT_ITEM, Include an entry point item in the metadata block, default=1 for Risc-V, 0 otherwise, type=bool, group=pico_crt0
 #ifndef PICO_CRT0_INCLUDE_PICOBIN_ENTRY_POINT_ITEM
 // On RISC-V the default entry point from bootrom is the start of the binary, but
 // we have our vtable at the start, so we must include an entry point
@@ -20,55 +23,72 @@
 #endif
 #endif
 
+// PICO_CONFIG: PICO_CRT0_INCLUDE_PICOBIN_BLOCK, Include a metadata block at the start of the image, default=PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM, type=bool, group=pico_crt0
 #ifndef PICO_CRT0_INCLUDE_PICOBIN_BLOCK
 #define PICO_CRT0_INCLUDE_PICOBIN_BLOCK PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM
 #endif
 
+// PICO_CONFIG: PICO_CRT0_INCLUDE_PICOBIN_END_BLOCK, Include a metadata block at the end of the image, default=1 for flash binaries with a metadata block at the start, type=bool, group=pico_crt0
 #ifndef PICO_CRT0_INCLUDE_PICOBIN_END_BLOCK
 #define PICO_CRT0_INCLUDE_PICOBIN_END_BLOCK (PICO_CRT0_INCLUDE_PICOBIN_BLOCK && !PICO_NO_FLASH)
 #endif
 
+// PICO_CONFIG: PICO_CRT0_IMAGE_TYPE_TBYB, Set the TBYB flag for the IMAGE_DEF which requires a flash update boot to boot it, default=0, type=bool, group=pico_crt0
+#ifndef PICO_CRT0_IMAGE_TYPE_TBYB
+#define PICO_CRT0_IMAGE_TYPE_TBYB 0
+#endif
+
 #if PICO_CRT0_IMAGE_TYPE_TBYB
 #define CRT0_TBYB_FLAG PICOBIN_IMAGE_TYPE_EXE_TBYB_BITS
 #else
 #define CRT0_TBYB_FLAG 0
 #endif
 
+// PICO_CONFIG: PICO_CRT0_VERSION_MAJOR, The major version for the metadata block (ignored if 0), default=0, type=int, group=pico_crt0
+// PICO_CONFIG: PICO_CRT0_VERSION_MINOR, The minor version for the metadata block (ignored if 0), default=0, type=int, group=pico_crt0
 #if defined(PICO_CRT0_VERSION_MINOR) && !defined(PICO_CRT0_VERSION_MAJOR)
 #define PICO_CRT0_VERSION_MAJOR 0
+#elif defined(PICO_CRT0_VERSION_MAJOR) && !defined(PICO_CRT0_VERSION_MINOR)
+#define PICO_CRT0_VERSION_MINOR 0
 #endif
 
-#if PICO_CRT0_INCLUDE_PICOBIN_BLOCK
-.section .embedded_block, "a"
-.p2align 2
-embedded_block:
-.word PICOBIN_BLOCK_MARKER_START
-
-#if PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM
-// include an IMAGE_TYPE item at the start so this block is a valid IMAGE_DEF block, and can be used as a basis
-// for booting the binary with a known type.
-.byte PICOBIN_BLOCK_ITEM_1BS_IMAGE_TYPE
-.byte 0x1 // 1 word
-#ifdef PICO_CRT0_IMAGE_TYPE_ITEM_VALUE
-.hword PICO_CRT0_IMAGE_TYPE_ITEM_VALUE
-#elif defined(__riscv)
-.hword PICOBIN_IMAGE_TYPE_IMAGE_TYPE_AS_BITS(EXE) | \
+// PICO_CONFIG: PICO_CRT0_IMAGE_TYPE_ITEM_VALUE, The IMAGE_TYPE value for the IMAGE_DEF, default=matching the PICO_PLATFORM, type=int, group=pico_crt0
+#ifndef PICO_CRT0_IMAGE_TYPE_ITEM_VALUE
+#if defined(__riscv)
+#define PICO_CRT0_IMAGE_TYPE_ITEM_VALUE \
+       PICOBIN_IMAGE_TYPE_IMAGE_TYPE_AS_BITS(EXE) | \
        PICOBIN_IMAGE_TYPE_EXE_CPU_AS_BITS(RISCV) | \
        PICOBIN_IMAGE_TYPE_EXE_CHIP_AS_BITS(RP2350) | \
        CRT0_TBYB_FLAG
 #elif PICO_RP2040
-.hword PICOBIN_IMAGE_TYPE_IMAGE_TYPE_AS_BITS(EXE) | \
+#define PICO_CRT0_IMAGE_TYPE_ITEM_VALUE \
+       PICOBIN_IMAGE_TYPE_IMAGE_TYPE_AS_BITS(EXE) | \
        PICOBIN_IMAGE_TYPE_EXE_SECURITY_AS_BITS(NS) | \
        PICOBIN_IMAGE_TYPE_EXE_CPU_AS_BITS(ARM) | \
        PICOBIN_IMAGE_TYPE_EXE_CHIP_AS_BITS(RP2040) | \
        CRT0_TBYB_FLAG
 #else
-.hword PICOBIN_IMAGE_TYPE_IMAGE_TYPE_AS_BITS(EXE) | \
+#define PICO_CRT0_IMAGE_TYPE_ITEM_VALUE \
+       PICOBIN_IMAGE_TYPE_IMAGE_TYPE_AS_BITS(EXE) | \
        PICOBIN_IMAGE_TYPE_EXE_SECURITY_AS_BITS(S) | \
        PICOBIN_IMAGE_TYPE_EXE_CPU_AS_BITS(ARM) | \
        PICOBIN_IMAGE_TYPE_EXE_CHIP_AS_BITS(RP2350) | \
        CRT0_TBYB_FLAG
 #endif
+#endif
+
+#if PICO_CRT0_INCLUDE_PICOBIN_BLOCK
+.section .embedded_block, "a"
+.p2align 2
+embedded_block:
+.word PICOBIN_BLOCK_MARKER_START
+
+#if PICO_CRT0_INCLUDE_PICOBIN_IMAGE_TYPE_ITEM
+// include an IMAGE_TYPE item at the start so this block is a valid IMAGE_DEF block, and can be used as a basis
+// for booting the binary with a known type.
+.byte PICOBIN_BLOCK_ITEM_1BS_IMAGE_TYPE
+.byte 0x1 // 1 word
+.hword PICO_CRT0_IMAGE_TYPE_ITEM_VALUE
 #else
 // if no image type, then add ignored item
 .byte PICOBIN_BLOCK_ITEM_2BS_IGNORED
@@ -80,11 +100,7 @@ embedded_block:
 .byte PICOBIN_BLOCK_ITEM_1BS_VERSION
 .byte 0x2 // 2 words
 .hword 0
-#ifdef PICO_CRT0_VERSION_MINOR
 .hword PICO_CRT0_VERSION_MINOR
-#else
-.hword 0
-#endif
 .hword PICO_CRT0_VERSION_MAJOR
 #endif