diff --git a/th01/hardware/ztext.c b/th01/hardware/ztext.c
index 1a72ef79..61b26a24 100644
--- a/th01/hardware/ztext.c
+++ b/th01/hardware/ztext.c
@@ -121,25 +121,25 @@ void z_text_putsa(tram_x_t x, tram_y_t y, int z_atrb, const char *str)
 	#define tx_chars(byte) ((char*)MK_FP(0xA000, p + byte))
 	#define tx_atrbs(byte) ((int16_t*)MK_FP(0xA200, p + byte))
 
-	if(z_atrb & 1) {
+	if(z_atrb & Z_ATRB_BLUE) {
 		hw_atrb += 0x20;
 	}
-	if(z_atrb & 4) {
+	if(z_atrb & Z_ATRB_RED) {
 		hw_atrb += 0x40;
 	}
-	if(z_atrb & 2) {
+	if(z_atrb & Z_ATRB_GREEN) {
 		hw_atrb += 0x80;
 	}
-	if(z_atrb & 0x800) {
+	if(z_atrb & Z_ATRB_VLINE) {
 		hw_atrb += 0x10;
 	}
-	if(z_atrb & 0x400) {
+	if(z_atrb & Z_ATRB_UNDERLINE) {
 		hw_atrb += TX_UNDERLINE;
 	}
-	if(z_atrb & 0x200) {
+	if(z_atrb & Z_ATRB_REVERSE) {
 		hw_atrb += TX_REVERSE;
 	}
-	if(z_atrb & 0x100) {
+	if(z_atrb & Z_ATRB_BLINK) {
 		hw_atrb += TX_BLINK;
 	}
 	hw_atrb += hw_atrb << 8;
diff --git a/th01/hardware/ztext.h b/th01/hardware/ztext.h
index ab9d8487..966c3566 100644
--- a/th01/hardware/ztext.h
+++ b/th01/hardware/ztext.h
@@ -9,6 +9,20 @@ typedef enum {
 	_z_text_cursor_t_FORCE_UINT16 = 0xFFFF
 } z_text_cursor_t;
 
+// Attribute bits for z_text_vputsa(), completely differing from the PC-98
+// hardware text attribute bits.
+#define Z_ATRB_BLUE     	0x1
+#define Z_ATRB_GREEN    	0x2
+#define Z_ATRB_RED      	0x4
+#define Z_ATRB_CYAN     	(Z_ATRB_BLUE | Z_ATRB_GREEN)
+#define Z_ATRB_MAGENTA  	(Z_ATRB_BLUE | Z_ATRB_RED)
+#define Z_ATRB_YELLOW   	(Z_ATRB_GREEN | Z_ATRB_RED)
+#define Z_ATRB_WHITE    	(Z_ATRB_BLUE | Z_ATRB_GREEN | Z_ATRB_RED)
+#define Z_ATRB_BLINK    	0x100
+#define Z_ATRB_REVERSE  	0x200
+#define Z_ATRB_UNDERLINE	0x400
+#define Z_ATRB_VLINE    	0x800
+
 void z_text_init(void);
 void z_text_25line(void);
 void z_text_20line(void);