diff --git a/core/SConscript.boardloader b/core/SConscript.boardloader
index 7f63250f3..c13ddd01a 100644
--- a/core/SConscript.boardloader
+++ b/core/SConscript.boardloader
@@ -99,10 +99,12 @@ if env.get('TREZOR_MODEL') == 'T':
     CPU_ASFLAGS = '-mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16'
     CPU_CCFLAGS = '-mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16 -mtune=cortex-m4 '
     CPU_MODEL   = 'STM32F427xx'
-else:
+elif env.get('TREZOR_MODEL') == '1':
     CPU_ASFLAGS = '-mthumb -mcpu=cortex-m3 -mfloat-abi=soft'
     CPU_CCFLAGS = '-mthumb -mtune=cortex-m3 -mcpu=cortex-m3 -mfloat-abi=soft '
     CPU_MODEL   = 'STM32F405xx'
+else:
+    raise ValueError('Unknown Trezor model')
 
 env.Replace(
     COPT=env.get('ENV').get('OPTIMIZE', '-Os'),
diff --git a/core/SConscript.bootloader b/core/SConscript.bootloader
index d06367712..826bd7710 100644
--- a/core/SConscript.bootloader
+++ b/core/SConscript.bootloader
@@ -125,10 +125,12 @@ if env.get('TREZOR_MODEL') == 'T':
     CPU_ASFLAGS = '-mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16'
     CPU_CCFLAGS = '-mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16 -mtune=cortex-m4 '
     CPU_MODEL   = 'STM32F427xx'
-else:
+elif env.get('TREZOR_MODEL') == '1':
     CPU_ASFLAGS = '-mthumb -mcpu=cortex-m3 -mfloat-abi=soft'
     CPU_CCFLAGS = '-mthumb -mtune=cortex-m3 -mcpu=cortex-m3 -mfloat-abi=soft '
     CPU_MODEL   = 'STM32F405xx'
+else:
+    raise ValueError('Unknown Trezor model')
 
 env.Replace(
     COPT=env.get('ENV').get('OPTIMIZE', '-Os'),
diff --git a/core/SConscript.firmware b/core/SConscript.firmware
index 96c07d8c2..5ef659e6d 100644
--- a/core/SConscript.firmware
+++ b/core/SConscript.firmware
@@ -369,10 +369,12 @@ if env.get('TREZOR_MODEL') == 'T':
     CPU_ASFLAGS = '-mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16'
     CPU_CCFLAGS = '-mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16 -mtune=cortex-m4 '
     CPU_MODEL   = 'STM32F427xx'
-else:
+elif env.get('TREZOR_MODEL') == '1':
     CPU_ASFLAGS = '-mthumb -mcpu=cortex-m3 -mfloat-abi=soft'
     CPU_CCFLAGS = '-mthumb -mtune=cortex-m3 -mcpu=cortex-m3 -mfloat-abi=soft '
     CPU_MODEL   = 'STM32F405xx'
+else:
+    raise ValueError('Unknown Trezor model')
 
 env.Replace(
     COPT=env.get('ENV').get('OPTIMIZE', '-Os'),
@@ -457,10 +459,12 @@ env.Ignore(hdr_moduledefs, qstr_generated)
 #
 
 if FROZEN:
-    if env.get('TREZOR_MODEL') == '1':
+    if env.get('TREZOR_MODEL') == 'T':
+        SOURCE_PY_DIR = 'src/'
+    elif env.get('TREZOR_MODEL') == '1':
         SOURCE_PY_DIR = 'src1/'
     else:
-        SOURCE_PY_DIR = 'src/'
+        raise ValueError('Unknown Trezor model')
 
     SOURCE_PY = Glob(SOURCE_PY_DIR + '*.py')
     SOURCE_PY.extend(Glob(SOURCE_PY_DIR + 'trezor/*.py'))
@@ -629,11 +633,13 @@ if env.get('TREZOR_MODEL') == 'T':
         '$HEADERTOOL $TARGET ' + ('-D' if ARGUMENTS.get('PRODUCTION', '0') == '0' else ''),
         '$DD if=$TARGET of=${TARGET}.p1 skip=0 bs=128k count=6',
     ]
-else:
+elif env.get('TREZOR_MODEL') == '1':
     action_bin=[
         '$OBJCOPY -O binary -j .header -j .flash -j .data $SOURCE $TARGET',
         '../legacy/bootloader/firmware_sign.py -f $TARGET',
     ]
+else:
+    raise ValueError('Unknown Trezor model')
 
 program_bin = env.Command(
     target='firmware.bin',
diff --git a/core/SConscript.prodtest b/core/SConscript.prodtest
index 77695ac4a..1e905de76 100644
--- a/core/SConscript.prodtest
+++ b/core/SConscript.prodtest
@@ -101,10 +101,12 @@ if env.get('TREZOR_MODEL') == 'T':
     CPU_ASFLAGS = '-mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16'
     CPU_CCFLAGS = '-mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16 -mtune=cortex-m4 '
     CPU_MODEL   = 'STM32F427xx'
-else:
+elif env.get('TREZOR_MODEL') == '1':
     CPU_ASFLAGS = '-mthumb -mcpu=cortex-m3 -mfloat-abi=soft'
     CPU_CCFLAGS = '-mthumb -mtune=cortex-m3 -mcpu=cortex-m3 -mfloat-abi=soft '
     CPU_MODEL   = 'STM32F405xx'
+else:
+    raise ValueError('Unknown Trezor model')
 
 env.Replace(
     COPT=env.get('ENV').get('OPTIMIZE', '-Os'),
diff --git a/core/SConscript.reflash b/core/SConscript.reflash
index 0369b9a8d..9515cd7ee 100644
--- a/core/SConscript.reflash
+++ b/core/SConscript.reflash
@@ -95,10 +95,12 @@ if env.get('TREZOR_MODEL') == 'T':
     CPU_ASFLAGS = '-mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16'
     CPU_CCFLAGS = '-mthumb -mcpu=cortex-m4 -mfloat-abi=hard -mfpu=fpv4-sp-d16 -mtune=cortex-m4 '
     CPU_MODEL   = 'STM32F427xx'
-else:
+elif env.get('TREZOR_MODEL') == '1':
     CPU_ASFLAGS = '-mthumb -mcpu=cortex-m3 -mfloat-abi=soft'
     CPU_CCFLAGS = '-mthumb -mtune=cortex-m3 -mcpu=cortex-m3 -mfloat-abi=soft '
     CPU_MODEL   = 'STM32F405xx'
+else:
+    raise ValueError('Unknown Trezor model')
 
 env.Replace(
     COPT=env.get('ENV').get('OPTIMIZE', '-Os'),
diff --git a/core/SConscript.unix b/core/SConscript.unix
index f1bff0901..140465048 100644
--- a/core/SConscript.unix
+++ b/core/SConscript.unix
@@ -425,10 +425,12 @@ env.Ignore(hdr_moduledefs, qstr_generated)
 #
 
 if FROZEN:
-    if env.get('TREZOR_MODEL') == '1':
+    if env.get('TREZOR_MODEL') == 'T':
+        SOURCE_PY_DIR = 'src/'
+    elif env.get('TREZOR_MODEL') == '1':
         SOURCE_PY_DIR = 'src1/'
     else:
-        SOURCE_PY_DIR = 'src/'
+        raise ValueError('Unknown Trezor model')
 
     SOURCE_PY = Glob(SOURCE_PY_DIR + '*.py')
     SOURCE_PY.extend(Glob(SOURCE_PY_DIR + 'trezor/*.py'))
diff --git a/core/embed/extmod/modtrezorconfig/norcow_config.h b/core/embed/extmod/modtrezorconfig/norcow_config.h
index 19b27acef..4b42b2aa5 100644
--- a/core/embed/extmod/modtrezorconfig/norcow_config.h
+++ b/core/embed/extmod/modtrezorconfig/norcow_config.h
@@ -26,17 +26,11 @@
 #define NORCOW_SECTOR_COUNT 2
 
 #if TREZOR_MODEL == T
-
 #define NORCOW_SECTOR_SIZE (64 * 1024)
-
 #elif TREZOR_MODEL == 1
-
 #define NORCOW_SECTOR_SIZE (16 * 1024)
-
 #else
-
-#error Unknown Trezor Model
-
+#error Unknown Trezor model
 #endif
 
 #define NORCOW_SECTORS \
diff --git a/core/embed/extmod/modtrezorui/display-stm32_t.h b/core/embed/extmod/modtrezorui/display-stm32_T.h
similarity index 100%
rename from core/embed/extmod/modtrezorui/display-stm32_t.h
rename to core/embed/extmod/modtrezorui/display-stm32_T.h
diff --git a/core/embed/extmod/modtrezorui/display-unix.h b/core/embed/extmod/modtrezorui/display-unix.h
index 05b7f0705..fb4efd64a 100644
--- a/core/embed/extmod/modtrezorui/display-unix.h
+++ b/core/embed/extmod/modtrezorui/display-unix.h
@@ -47,7 +47,7 @@
 #define TOUCH_OFFSET_Y 92
 
 #else
-#error Unknown Trezor Model
+#error Unknown Trezor model
 #endif
 
 static SDL_Renderer *RENDERER;
diff --git a/core/embed/extmod/modtrezorui/display.c b/core/embed/extmod/modtrezorui/display.c
index 3c0223631..9ffd3c49b 100644
--- a/core/embed/extmod/modtrezorui/display.c
+++ b/core/embed/extmod/modtrezorui/display.c
@@ -54,9 +54,11 @@ static struct { int x, y; } DISPLAY_OFFSET;
 #include "display-unix.h"
 #else
 #if TREZOR_MODEL == T
-#include "display-stm32_t.h"
+#include "display-stm32_T.h"
 #elif TREZOR_MODEL == 1
 #include "display-stm32_1.h"
+#else
+#error Unknown Trezor model
 #endif
 #endif
 
diff --git a/core/embed/extmod/modtrezorui/display.h b/core/embed/extmod/modtrezorui/display.h
index c34b27e51..f2bc746da 100644
--- a/core/embed/extmod/modtrezorui/display.h
+++ b/core/embed/extmod/modtrezorui/display.h
@@ -39,7 +39,7 @@
 #define DISPLAY_RESY 64
 
 #else
-#error Unknown Trezor Model
+#error Unknown Trezor model
 #endif
 
 #define FONT_BPP 4
diff --git a/core/embed/firmware/header.S b/core/embed/firmware/header.S
index 242ad0f2a..858719042 100644
--- a/core/embed/firmware/header.S
+++ b/core/embed/firmware/header.S
@@ -26,12 +26,12 @@ g_header:
     . = . + 8                        // reserved
     . = . + 512                      // hash1 ... hash16
 
-#if TREZOR_MODEL != 1
+#if TREZOR_MODEL == T
 // model T header specifics
     . = . + 415                      // reserved
     .byte 0                          // sigmask
     . = . + 64                       // sig
-#else
+#elif TREZOR_MODEL == 1
 // model 1 header specifics
     . = . + 64                       // sig1
     . = . + 64                       // sig2
@@ -41,6 +41,8 @@ g_header:
     .byte 0                          // sigindex3
     . = . + 220                      // reserved
     . = . + 65                       // reserved
+#else
+#error Unknown Trezor model
 #endif
 
 g_header_end:
diff --git a/core/embed/trezorhal/flash.c b/core/embed/trezorhal/flash.c
index 2b90e45be..8808a6794 100644
--- a/core/embed/trezorhal/flash.c
+++ b/core/embed/trezorhal/flash.c
@@ -55,6 +55,8 @@ static const uint32_t FLASH_SECTOR_TABLE[FLASH_SECTOR_COUNT + 1] = {
     [24] = 0x08200000,  // last element - not a valid sector
 #elif TREZOR_MODEL == 1
     [12] = 0x08100000,  // last element - not a valid sector
+#else
+#error Unknown Trezor model
 #endif
 };
 
diff --git a/core/embed/trezorhal/flash.h b/core/embed/trezorhal/flash.h
index 64a9aef7c..8bd0bc2c9 100644
--- a/core/embed/trezorhal/flash.h
+++ b/core/embed/trezorhal/flash.h
@@ -30,6 +30,8 @@
 #define FLASH_SECTOR_COUNT 24
 #elif TREZOR_MODEL == 1
 #define FLASH_SECTOR_COUNT 12
+#else
+#error Unknown Trezor model
 #endif
 
 #define FLASH_SECTOR_BOARDLOADER_START 0
@@ -44,6 +46,8 @@
 #elif TREZOR_MODEL == 1
 #define FLASH_SECTOR_STORAGE_1 2
 #define FLASH_SECTOR_STORAGE_2 3
+#else
+#error Unknown Trezor model
 #endif
 
 #define FLASH_SECTOR_BOOTLOADER 5
diff --git a/core/embed/trezorhal/touch.c b/core/embed/trezorhal/touch.c
index b5b64d143..2002fec6b 100644
--- a/core/embed/trezorhal/touch.c
+++ b/core/embed/trezorhal/touch.c
@@ -21,11 +21,11 @@
 #include "touch.h"
 
 #if TREZOR_MODEL == T
-#include "touch_t.h"
+#include "touch_T.h"
 #elif TREZOR_MODEL == 1
 #include "touch_1.h"
 #else
-#error Unknown Trezor Model
+#error Unknown Trezor model
 #endif
 
 uint32_t touch_click(void) {
diff --git a/core/embed/trezorhal/touch_t.h b/core/embed/trezorhal/touch_T.h
similarity index 100%
rename from core/embed/trezorhal/touch_t.h
rename to core/embed/trezorhal/touch_T.h
diff --git a/core/embed/unix/flash.c b/core/embed/unix/flash.c
index a0de59e13..30f7ab5a4 100644
--- a/core/embed/unix/flash.c
+++ b/core/embed/unix/flash.c
@@ -63,6 +63,8 @@ static const uint32_t FLASH_SECTOR_TABLE[FLASH_SECTOR_COUNT + 1] = {
     [24] = 0x08200000,  // last element - not a valid sector
 #elif TREZOR_MODEL == 1
     [12] = 0x08100000,  // last element - not a valid sector
+#else
+#error Unknown Trezor model
 #endif
 };
 
diff --git a/storage/tests/c/norcow_config.h b/storage/tests/c/norcow_config.h
index 7f0efb637..64cc174c6 100644
--- a/storage/tests/c/norcow_config.h
+++ b/storage/tests/c/norcow_config.h
@@ -31,10 +31,12 @@
  * The length of the sector header in bytes. The header is preserved between
  * sector erasures.
  */
-#if TREZOR_MODEL == 1
+#if TREZOR_MODEL == T
+#define NORCOW_HEADER_LEN 0
+#elif TREZOR_MODEL == 1
 #define NORCOW_HEADER_LEN (0x100)
 #else
-#define NORCOW_HEADER_LEN 0
+#error Unknown Trezor model
 #endif
 
 /*