diff --git a/Makefile b/Makefile
index b3acc2a..d672a52 100644
--- a/Makefile
+++ b/Makefile
@@ -21,7 +21,7 @@
 CROSS = arm-none-eabi-
 CC = gcc
 AS = as
-AR = ar
+AR = tools/rba
 OBJCOPY = objcopy
 STRIP = strip
 
@@ -46,11 +46,10 @@ INITRD = initrd.img
 
 all: $(OUT)
 
-#@$(CROSS)$(STRIP) --only-keep-debug $(OUT)
 $(OUT): $(OFILES) initrd/init libinterp.a
 	@echo "  INITRD " $(INITRD)
 	@rm -f $(INITRD)
-	@$(CROSS)$(AR) r $(INITRD) initrd/*
+	@$(AR) $(INITRD) initrd/*
 	@$(CROSS)$(OBJCOPY) -B arm -I binary -O elf32-littlearm $(INITRD) out/initrd.img.o
 	@echo "  LINK   " $(OUT)
 	@$(CROSS)$(CC) $(CFLAGS) $(LFLAGS) out/*.o -o $(OUT) -L. -linterp -lm
diff --git a/include/initrd.h b/include/initrd.h
index 1f7c0b6..3957066 100644
--- a/include/initrd.h
+++ b/include/initrd.h
@@ -26,45 +26,31 @@
 
 #include <stdint.h>
 
-/**
- * Structure for the archive's header.
- */
-typedef struct
-{
-	char signature[8]; /**< The archive's signature */
-} __attribute__ ((packed)) initrd_header;
-
-/**
- * Structure for a file entry in the archive.
- */
-typedef struct 
-{
-	char name[16];      /**< The name of the file */
-	uint8_t unused[32]; /**< Unused information */
-	char size[10];      /**< The file's size in bytes (as string) */
-	char sig[2];        /**< A signature to start file data */
-} __attribute__ ((packed)) initrd_file;
-
 /**
  * Confirms the initrd image is loaded and valid.
  * @return non-zero if valid image found
  */
 uint8_t initrd_validate(void);
 
+/**
+ * Gets the file name of the index'th file in the archive.
+ * @param index the index of the file
+ * @return the file's name, or zero if not found
+ */
+char *initrd_getfile(uint32_t index);
+
 /**
  * Gets contents of the given file.
  * @param name the file's name
  * @return pointer to file data, null if not found
  */
-char *initrd_getfile(const char *name);
+char *initrd_readfile(const char *name);
 
 /**
  * Gets the size of the given file.
  * @param name the file's name
  * @return the file's size, in bytes
  */
-uint32_t initrd_getfilesize(const char *name);
-
-char *initrd_getnfile(unsigned int index);
+uint32_t initrd_filesize(const char *name);
 
 #endif // INITRD_H_
diff --git a/initrd.c b/initrd.c
deleted file mode 100644
index 3f36cd9..0000000
--- a/initrd.c
+++ /dev/null
@@ -1,42 +0,0 @@
-#include <stdint.h>
-#include <string.h>
-
-extern uint8_t *initrd_start;
-extern uint32_t initrd_size;
-
-char *getfile(uint32_t offset)
-{
-	char *ptr = initrd_start;
-	for (uint32_t i = 0; i < offset; i++) {
-		uint32_t len = *((uint32_t *)ptr);
-		uint32_t datalen = *((uint32_t *)(ptr + 4 + len));
-		ptr += len + datalen + 8;
-		if (ptr >= (char *)(initrd_start + initrd_size))
-			return 0;
-	}
-
-	return ptr;
-}
-
-char *readfile(const char *name)
-{
-	char *ptr;
-	for (uint32_t i = 0; ptr = getfile(i), ptr != 0; i++) {
-		uint32_t len = *((uint32_t *)ptr);
-		if (!strncmp(name, ptr + 4, len))
-			return ptr + len + 8;
-	}
-	return 0;
-}
-
-uint32_t filesize(const char *name)
-{
-	char *ptr;
-	for (uint32_t i = 0; ptr = getfile(i), ptr != 0; i++) {
-		uint32_t len = *((uint32_t *)ptr);
-		if (!strncmp(name, ptr + 4, len))
-			return *((uint32_t *)ptr + len + 4);
-	}
-	return 0;
-}
-
diff --git a/boot b/initrd/boot
similarity index 100%
rename from boot
rename to initrd/boot
diff --git a/libinterp.a b/libinterp.a
index 7c9e7a9..04391e1 100644
Binary files a/libinterp.a and b/libinterp.a differ
diff --git a/src/initrd.c b/src/initrd.c
index b8e8d09..1534210 100644
--- a/src/initrd.c
+++ b/src/initrd.c
@@ -1,9 +1,6 @@
 /**
  * @file initrd.c
  * Initrd image support
- * An archive file (made with ar) can be linked into the final executable to
- * allow files to be loaded in memory on boot. See mkinitrd.sh or the Makefile
- * for more info.
  *
  * Copyright (C) 2018 Clyne Sullivan
  *
@@ -21,110 +18,57 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
+/**
+ * The format of the initrd file is custom; made with the 'rba' utility.
+ */
+
 #include <initrd.h>
+#include <string.h>
 
 extern uint8_t _binary_initrd_img_start[];
 extern uint8_t _binary_initrd_img_size[];
 
-static const void *initrd_start = (void *)_binary_initrd_img_start;
+static const uint8_t *initrd_start = (uint8_t *)_binary_initrd_img_start;
 static const uint32_t initrd_size = (uint32_t)_binary_initrd_img_size;
 
-static const char *initrd_sig = "!<arch>\n";
-
 uint8_t initrd_validate(void)
 {
-	initrd_header *header = (initrd_header *)initrd_start;
-	for (uint8_t i = 0; i < 8; i++) {
-		if (header->signature[i] != initrd_sig[i])
-			return 0;
-	}
-
-	return 1;
+	return 1; // TODO maybe add header/signature to archiver?
 }
 
-uint8_t initrd_nametest(char *file, const char *want)
+char *initrd_getfile(uint32_t offset)
 {
-	for (uint8_t i = 0; i < 16; i++) {
-		if (want[i] == '\0')
-			return (file[i] == '/');
-		else if (want[i] != file[i])
+	char *ptr = initrd_start;
+	for (uint32_t i = 0; i < offset; i++) {
+		uint32_t len = *((uint32_t *)ptr);
+		uint32_t datalen = *((uint32_t *)(ptr + 4 + len));
+		ptr += len + datalen + 8;
+		if (ptr >= (char *)(initrd_start + initrd_size))
 			return 0;
 	}
 
-	return 0;
-}
-
-uint32_t ipow10(uint8_t n)
-{
-	uint32_t i = 1;
-	while (n--)
-		i *= 10;
-	return i;
-}
-
-uint32_t initrd_getsize(initrd_file *file)
-{
-	uint32_t size = 0;
-	char *p = file->size + 10;
-	while (*--p == ' ');
-
-	for (int8_t i = p - file->size, j = 0; i >= 0; i--, j++)
-		size += (*p-- - '0') * ipow10(j);
-
-	return size;
+	return ptr;
 }
 
-initrd_file *initrd_getfileptr(const char *name)
+char *initrd_readfile(const char *name)
 {
-	initrd_file *file = (initrd_file *)((uint8_t *)initrd_start + sizeof(initrd_header));
-	uint32_t offset = sizeof(initrd_header);
-
-	while (offset < initrd_size) {
-		if (initrd_nametest(file->name, name))
-			return file;
-		uint32_t size = initrd_getsize(file) + sizeof(initrd_file);
-		offset += size;
-		file = (initrd_file *)((uint8_t *)file + size + 1);
+	char *ptr;
+	for (uint32_t i = 0; ptr = initrd_getfile(i), ptr != 0; i++) {
+		uint32_t len = *((uint32_t *)ptr);
+		if (!strncmp(name, ptr + 4, len))
+			return ptr + len + 8;
 	}
-
 	return 0;
 }
 
-char *initrd_getnfile(unsigned int index)
+uint32_t initrd_filesize(const char *name)
 {
-	initrd_file *file = (initrd_file *)((uint8_t *)initrd_start + sizeof(initrd_header));
-	uint32_t offset = sizeof(initrd_header);
-
-	for (unsigned int i = 0; i < index; i++) {
-		uint32_t size = initrd_getsize(file) + sizeof(initrd_file);
-		offset += size;
-		file = (initrd_file *)((uint8_t *)file + size);
-		if (file->name[0] == '\n')
-			file = (initrd_file *)((uint32_t)file + 1);
+	char *ptr;
+	for (uint32_t i = 0; ptr = initrd_getfile(i), ptr != 0; i++) {
+		uint32_t len = *((uint32_t *)ptr);
+		if (!strncmp(name, ptr + 4, len))
+			return *((uint32_t *)(ptr + len + 4));
 	}
-	if ((uint32_t)file >= (uint32_t)initrd_start + initrd_size)
-		return 0;
-	return file->name;
-}
-
-char *initrd_getfile(const char *name)
-{
-	initrd_file *file = initrd_getfileptr(name);
-	if (file == 0)
-		return 0;
-
-
-	char *ptr = (char *)file + sizeof(initrd_file);
-	ptr[initrd_getsize(file) - 1] = 0;
-	return ptr;
-}
-
-uint32_t initrd_getfilesize(const char *name)
-{
-	initrd_file *file = initrd_getfileptr(name);
-	if (file == 0)
-		return 0;
-
-	return initrd_getsize(file);
+	return 0;
 }
 
diff --git a/src/keypad.c b/src/keypad.c
index 5b04eec..22fc967 100644
--- a/src/keypad.c
+++ b/src/keypad.c
@@ -53,16 +53,29 @@ static const port_t keypad_cols[COLS] = {
 	{ COL_3 }, { COL_4 }
 };
 
+#define K_2ND  0x000000FF
+#define K_HOLD 0x000001FF
+
 static const char keypad_map[ROWS * COLS * 4] = {
-	"&\0\0\0" "|\0\0\0" "pi\0\0"  "==\0\0"   "!=\0\0"
-	"x\0\0\0" "y\0\0\0" "z\0\0\0"  "=\0\0\0"  "sin\0"
-	"7\0\0\0" "8\0\0\0" "9\0\0\0"  "(\0\0\0"  ")\0\0\0"
-	"4\0\0\0" "5\0\0\0" "6\0\0\0"  "/\0\0\0"  "%\0\0\0"
-	"1\0\0\0" "2\0\0\0" "3\0\0\0"  "*\0\0\0"  "-\0\0\0"
-	".\0\0\0" "0\0\0\0" "\b\0\0\0" "\n\0\0\0" "+\0\0\0"
+	"\xFF\0\0\0" ">\0\0\0" ">=\0\0"   "==\0\0"   "=\0\0\0"
+	"x\0\0\0"    "<\0\0\0" "<=\0\0"   "!=\0\0"   "%\0\0\0"
+	"7\0\0\0"    "8\0\0\0" "9\0\0\0"  "(\0\0\0"  ")\0\0\0"
+	"4\0\0\0"    "5\0\0\0" "6\0\0\0"  "/\0\0\0"  "*\0\0\0"
+	"1\0\0\0"    "2\0\0\0" "3\0\0\0"  "-\0\0\0"  "+\0\0\0"
+	".\0\0\0"    "0\0\0\0" "\0\0\0\0" "\b\0\0\0" "\n\0\0\0"
+};
+
+static const char keypad_map_2nd[ROWS * COLS * 4] = {
+	"a\0\0\0" "b\0\0\0"  "c\0\0\0"  "d\0\0\0"  "e\0\0\0"
+	"f\0\0\0" "g\0\0\0"  "h\0\0\0"  "i\0\0\0"  "j\0\0\0"
+	"k\0\0\0" "l\0\0\0"  "m\0\0\0"  "n\0\0\0"  "o\0\0\0"
+	"p\0\0\0" "q\0\0\0"  "r\0\0\0"  "s\0\0\0"  "t\0\0\0"
+	"u\0\0\0" "v\0\0\0"  "w\0\0\0"  "x\0\0\0"  "y\0\0\0"
+	"z\0\0\0" "\0\0\0\0" "\0\0\0\0" "\0\0\0\0" "\xFF\x01\0\0"
 };
 
-#define KEY(r, c, i) keypad_map[r * COLS * 4 + c * 4 + i]
+#define KEY(r, c, i) map[r * COLS * 4 + c * 4 + i]
+#define KEYCODE(r, c) *((uint32_t *)(map + (r * COLS * 4 + c * 4)))
 
 #define BUFFER_SIZE 8
 static char keypad_buffer[BUFFER_SIZE];
@@ -71,12 +84,24 @@ static int keypad_buffer_pos = -1;
 void keypad_task(void)
 {
 	unsigned int col = 0;
+	unsigned char use2nd = 0;
+	unsigned char hold = 0;
 	while (1) {
 		gpio_dout(keypad_cols[col].port, keypad_cols[col].pin, 1);
 		delay(10);
 		for (unsigned int row = 0; row < ROWS; row++) {
 			if (gpio_din(keypad_rows[row].port, keypad_rows[row].pin)) {
-				if (keypad_buffer_pos < BUFFER_SIZE) {
+				char *map = (use2nd == 0) ? keypad_map : keypad_map_2nd;
+				if (KEYCODE(row, col) == K_2ND) {
+					use2nd = 1;
+				} else if (KEYCODE(row, col) == K_HOLD) {
+					if (use2nd != 0) {
+						if ((hold ^= 1) == 0)
+							use2nd = 0;
+					}
+				} else if (keypad_buffer_pos < BUFFER_SIZE) {
+					if (use2nd != 0 && hold == 0)
+						use2nd = 0;
 					for (unsigned int i = 0; KEY(row, col, i) != '\0'; i++)
 						keypad_buffer[++keypad_buffer_pos] = KEY(row, col, i);
 				}
diff --git a/src/main.c b/src/main.c
index d21407a..b39053a 100644
--- a/src/main.c
+++ b/src/main.c
@@ -90,7 +90,7 @@ void task_interpreter(void)
 	instance *it = inewinstance();
 	script_loadlib(it);
 
-	char *s = initrd_getfile("init");
+	char *s = initrd_readfile("init");
 	if (s == 0) {
 		dsp_puts("can't find init");
 		goto end;
@@ -98,7 +98,7 @@ void task_interpreter(void)
 
 	char *linebuf = (char *)malloc(120);
 	uint32_t i = 0, prev = 0, lc;
-	uint32_t size = initrd_getfilesize("init");
+	uint32_t size = initrd_filesize("init");
 	int ret = 0;
 	while (i < size) {
 		for (; s[i] != '\n' && s[i] != '\0'; i++);
diff --git a/src/script.c b/src/script.c
index 733bc4a..95d62c0 100644
--- a/src/script.c
+++ b/src/script.c
@@ -107,7 +107,7 @@ int script_filemenu(instance *it)
 	char *fname;
 	strncpy(listbuf, " : \0", 4);
 	dsp_puts("Choose a file: \n");
-	for (unsigned int i = 0; (fname = initrd_getnfile(i)) != 0; i++) {
+	for (unsigned int i = 0; (fname = initrd_getfile(i)) != 0; i++) {
 		listbuf[0] = i + '0';
 		dsp_puts(listbuf);
 		dsp_puts(strncpy(buf, fname, 16));
diff --git a/src/stdlib.c b/src/stdlib.c
index 950f356..b7b11dc 100644
--- a/src/stdlib.c
+++ b/src/stdlib.c
@@ -23,8 +23,8 @@
 #include <stdlib.h>
 
 #include <ctype.h>
+#include <heap.h>
 #include <stdarg.h>
-#include <stdint.h>
 #include <string.h>
 
 extern char *itoa(int, char *, int);
@@ -61,7 +61,7 @@ char *snprintf(char *buf, unsigned int max, const char *format, ...)
 				itoa(va_arg(args, unsigned int), nbuf, 16);
 				break;
 			case 'f':
-				itoa((int)va_arg(args, double), nbuf, 10);
+				itoa(va_arg(args, double), nbuf, 10);
 				break;
 			default:
 				buf[off++] = format[i];
diff --git a/rba b/tools/rba
similarity index 100%
rename from rba
rename to tools/rba