This commit is contained in:
sherlock 2025-10-29 14:50:21 +05:30
parent 1d9b668496
commit 1790b7fdb8
3 changed files with 311 additions and 459 deletions

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@ -1,458 +0,0 @@
#include <LPC17xx.h>
/* PORT MAPPING:
* KEYPAD MATRIX (4x4):
* Columns: P0.15 - P0.18 (Output, pulled high, scan low)
* Rows: P0.19 - P0.22 (Input, pulled high internally)
*
* Layout: 0 1 2 3
* 4 5 6 7
* 8 9 A B
* C D E F
*
* 7-SEGMENT DISPLAY:
* Segments: P0.4 - P0.11 (a-g + dp)
* Digit Enable: P1.23 (active high)
*
* LCD (16x2):
* Data: P0.23 - P0.26 (D4-D7, 4-bit mode)
* RS: P0.27
* EN: P0.28
*
* MODE BUTTON:
* P2.12 (Input, internal pull-up)
*
* KEY FUNCTIONS:
* 0-9, A-F: Digit input (valid based on current base)
*
* OPERATOR MODE (Hold Key 0 + another key):
* Key 0 + B: Addition (+)
* Key 0 + C: Clear (C)
* Key 0 + D: Subtraction (-)
* Key 0 + E: Multiplication (*)
* Key 0 + F: Equals (=)
*
* P2.12 Button: Mode selection (cycles: DEC->BIN->OCT->HEX)
*
* 7-SEGMENT STATE DISPLAY:
* '0' - Cleared/Reset state
* '1' - Input mode (entering numbers)
* '2' with DP - Operation pending (waiting for 2nd number)
* '3' with DP - Result ready (showing calculation result)
*/
// 7-Segment patterns
const unsigned char seven_seg[16] = {
0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,
0x7F,0x6F,0x77,0x7C,0x39,0x5E,0x79,0x71
};
// Keypad defines
#define COL_BASE 15
#define ROW_BASE 19
#define COL_MASK (0x0F << COL_BASE)
#define ROW_MASK (0x0F << ROW_BASE)
// 7-Segment defines
#define SEG_SHIFT 4
#define DIGIT_EN (1<<23)
// LCD defines
#define LCD_DATA_SHIFT 23
#define LCD_DATA_MASK (0x0F << LCD_DATA_SHIFT)
#define LCD_RS (1<<27)
#define LCD_EN (1<<28)
// Mode button defines
#define MODE_BUTTON (1<<12)
// Calculator states
#define MODE_BIN 2
#define MODE_OCT 8
#define MODE_DEC 10
#define MODE_HEX 16
#define OP_NONE 0
#define OP_ADD 1
#define OP_SUB 2
#define OP_MUL 3
// Global variables
int input_num = 0;
int stored_num = 0;
int result = 0;
unsigned int current_base = MODE_DEC;
unsigned int operation = OP_NONE;
unsigned char lcd_flag = 0;
unsigned char result_displayed = 0; // NEW: Track if showing result
void delay(volatile unsigned int d){
while(d--) __NOP();
}
void lcd_delay(unsigned long r){
unsigned long i;
for(i=0; i<r; i++);
}
void lcd_write_nibble(unsigned char nibble, unsigned char is_data){
unsigned long temp;
temp = (nibble & 0x0F) << LCD_DATA_SHIFT;
LPC_GPIO0->FIOPIN = (LPC_GPIO0->FIOPIN & ~LCD_DATA_MASK) | temp;
if(is_data)
LPC_GPIO0->FIOSET = LCD_RS;
else
LPC_GPIO0->FIOCLR = LCD_RS;
LPC_GPIO0->FIOSET = LCD_EN;
lcd_delay(100);
LPC_GPIO0->FIOCLR = LCD_EN;
lcd_delay(500000);
}
void lcd_cmd(unsigned char cmd){
lcd_write_nibble(cmd >> 4, 0);
lcd_write_nibble(cmd, 0);
}
void lcd_data(unsigned char data){
lcd_write_nibble(data >> 4, 1);
lcd_write_nibble(data, 1);
}
void lcd_init(void){
lcd_delay(5000000);
lcd_write_nibble(0x03, 0);
lcd_delay(500000);
lcd_write_nibble(0x03, 0);
lcd_delay(500000);
lcd_write_nibble(0x03, 0);
lcd_delay(500000);
lcd_write_nibble(0x02, 0);
lcd_delay(500000);
lcd_cmd(0x28);
lcd_cmd(0x0C);
lcd_cmd(0x01);
lcd_delay(500000);
lcd_cmd(0x06);
}
void lcd_print_str(const char* str){
while(*str){
lcd_data(*str++);
}
}
void lcd_print_num(int num, unsigned int base){
char buffer[17];
int i = 0;
// For non-decimal bases, show as unsigned (two's complement representation)
if(base != MODE_DEC){
unsigned int unum = (unsigned int)num;
if(unum == 0){
lcd_data('0');
return;
}
while(unum > 0 && i < 16){
unsigned int digit = unum % base;
if(digit < 10)
buffer[i++] = '0' + digit;
else
buffer[i++] = 'A' + (digit - 10);
unum = unum / base;
}
} else {
// Decimal mode: handle negative with minus sign
if(num < 0){
lcd_data('-');
num = -num;
}
if(num == 0){
lcd_data('0');
return;
}
while(num > 0 && i < 16){
buffer[i++] = '0' + (num % 10);
num = num / 10;
}
}
while(i > 0){
lcd_data(buffer[--i]);
}
}
void display_mode(void){
lcd_cmd(0x80);
lcd_print_str("Mode: ");
if(current_base == MODE_BIN)
lcd_print_str("BIN ");
else if(current_base == MODE_OCT)
lcd_print_str("OCT ");
else if(current_base == MODE_DEC)
lcd_print_str("DEC ");
else
lcd_print_str("HEX ");
}
void display_input(void){
lcd_cmd(0xC0);
lcd_print_str("Inp: ");
lcd_print_num(input_num, current_base);
lcd_print_str(" ");
}
void display_operator_feedback(const char* op_symbol){
// Brief feedback on line 2
lcd_cmd(0xC0);
lcd_print_str("Op: ");
lcd_print_str(op_symbol);
lcd_print_str(" ");
delay(100000); // Brief delay to show feedback
display_input(); // Return to showing input
}
unsigned int scan_keypad(void){
unsigned int col, row;
unsigned int row_bits;
for(col=0; col<4; col++){
LPC_GPIO0->FIOSET = COL_MASK;
delay(50);
LPC_GPIO0->FIOCLR = (1 << (COL_BASE + col));
delay(200);
row_bits = (LPC_GPIO0->FIOPIN & ROW_MASK) >> ROW_BASE;
if(row_bits != 0x0F){
for(row=0; row<4; row++){
if((row_bits & (1<<row)) == 0){
LPC_GPIO0->FIOSET = COL_MASK;
return col*4 + row;
}
}
}
}
LPC_GPIO0->FIOSET = COL_MASK;
return 0xFF;
}
// Check if Key 0 is currently pressed (shift key)
unsigned int is_key0_pressed(void){
unsigned int col = 0; // Key 0 is at column 0, row 0
unsigned int row_bits;
LPC_GPIO0->FIOSET = COL_MASK;
delay(50);
LPC_GPIO0->FIOCLR = (1 << (COL_BASE + col));
delay(200);
row_bits = (LPC_GPIO0->FIOPIN & ROW_MASK) >> ROW_BASE;
LPC_GPIO0->FIOSET = COL_MASK;
// Check if row 0 is pressed (Key 0)
return ((row_bits & 0x01) == 0) ? 1 : 0;
}
unsigned int scan_mode_button(void){
// Return 1 if button is pressed (active low), 0 if not pressed
return ((LPC_GPIO2->FIOPIN & MODE_BUTTON) == 0) ? 1 : 0;
}
unsigned int is_valid_digit(unsigned int key){
if(key >= 16) return 0;
if(current_base == MODE_BIN && key >= 2) return 0;
if(current_base == MODE_OCT && key >= 8) return 0;
if(current_base == MODE_DEC && key >= 10) return 0;
// In HEX mode, all keys 0-15 are valid digits!
return 1;
}
void change_mode(void){
if(current_base == MODE_DEC)
current_base = MODE_BIN;
else if(current_base == MODE_BIN)
current_base = MODE_OCT;
else if(current_base == MODE_OCT)
current_base = MODE_HEX;
else
current_base = MODE_DEC;
display_mode();
}
int main(void){
unsigned int key, last_key = 0xFF;
unsigned int stable = 0;
unsigned int button_state, last_button_state = 0;
unsigned int button_stable = 0;
unsigned int shift_active = 0;
// Configure pins
LPC_PINCON->PINSEL0 = 0;
LPC_PINCON->PINSEL1 = 0;
LPC_PINCON->PINSEL3 = 0;
LPC_PINCON->PINSEL4 = 0; // Configure P2.12
// Keypad: Columns output, Rows input
LPC_GPIO0->FIODIR |= COL_MASK;
LPC_GPIO0->FIODIR &= ~ROW_MASK;
LPC_GPIO0->FIOSET = COL_MASK;
// Mode button: Input with internal pull-up
LPC_GPIO2->FIODIR &= ~MODE_BUTTON; // Set as input
// 7-Segment
LPC_GPIO0->FIODIR |= (0xFF << SEG_SHIFT);
LPC_GPIO1->FIODIR |= DIGIT_EN;
// LCD
LPC_GPIO0->FIODIR |= LCD_DATA_MASK | LCD_RS | LCD_EN;
lcd_init();
display_mode();
display_input();
for(;;){
// Check if shift key (Key 0) is being held
shift_active = is_key0_pressed();
// Scan for other keys
key = scan_keypad();
button_state = scan_mode_button();
// Debounce keypad
if(key == last_key){
if(stable < 5) stable++;
} else {
last_key = key;
stable = 0;
}
// Debounce mode button
if(button_state == last_button_state){
if(button_stable < 5) button_stable++;
} else {
last_button_state = button_state;
button_stable = 0;
}
// Handle mode button press
if(button_stable == 3 && button_state == 1){
change_mode();
button_stable = 5; // Prevent multiple triggers
}
// Handle keypad input
if(stable == 3 && key != 0xFF){
// Key pressed and stable
// If Key 0 is also pressed, we're in operator mode
if(shift_active && key != 0){
// OPERATOR MODE (Key 0 + another key)
if(key == 11){ // Key 0 + B = Addition
stored_num = input_num;
operation = OP_ADD;
input_num = 0;
result_displayed = 0; // Clear result flag
display_operator_feedback("+");
}
else if(key == 12){ // Key 0 + C = Clear
input_num = 0;
stored_num = 0;
operation = OP_NONE;
result = 0;
result_displayed = 0; // Clear result flag
display_operator_feedback("CLR");
}
else if(key == 13){ // Key 0 + D = Subtraction
stored_num = input_num;
operation = OP_SUB;
input_num = 0;
result_displayed = 0; // Clear result flag
display_operator_feedback("-");
}
else if(key == 14){ // Key 0 + E = Multiplication
stored_num = input_num;
operation = OP_MUL;
input_num = 0;
result_displayed = 0; // Clear result flag
display_operator_feedback("*");
}
else if(key == 15){ // Key 0 + F = Equals
if(operation == OP_ADD)
result = stored_num + input_num;
else if(operation == OP_SUB)
result = stored_num - input_num;
else if(operation == OP_MUL)
result = stored_num * input_num;
else
result = input_num;
lcd_cmd(0xC0);
lcd_print_str("Res: ");
lcd_print_num(result, current_base);
lcd_print_str(" ");
input_num = result;
operation = OP_NONE;
result_displayed = 1; // Set result flag
}
}
else {
// NORMAL MODE - Digit input
if(is_valid_digit(key)){
result_displayed = 0; // Clear result flag on new input
input_num = input_num * current_base + key;
// Handle overflow with wrap-around for signed int
if(input_num > 32767) input_num = input_num % 32768;
if(input_num < -32768) input_num = -32768;
display_input();
}
}
stable = 5; // Prevent repeated triggers
}
// ===== STATE MACHINE DISPLAY ON 7-SEGMENT =====
unsigned int seg_pattern;
// State 1: INPUT MODE (Display '1')
// - No operation pending
// - Not showing a result
if(operation == OP_NONE && result_displayed == 0) {
seg_pattern = 0x06; // Display '1'
}
// State 2: OPERATION PENDING (Display '2' with DP)
// - Operation selected
// - Waiting for second number
else if(operation != OP_NONE) {
seg_pattern = 0x5B | 0x80; // Display '2' with decimal point ON
}
// State 3: RESULT READY (Display '3' with DP)
// - Result was just calculated
// - Showing the result
else if(result_displayed == 1) {
seg_pattern = 0x4F | 0x80; // Display '3' with decimal point ON
}
// State 0: CLEARED/RESET (Display '0')
// - Everything is zero
// - Fallback state
else {
seg_pattern = 0x3F; // Display '0'
}
// Update the 7-segment display
LPC_GPIO0->FIOCLR = (0xFF << SEG_SHIFT);
LPC_GPIO0->FIOSET = (seg_pattern << SEG_SHIFT);
LPC_GPIO1->FIOSET = DIGIT_EN;
delay(3000);
}
}

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@ -0,0 +1,309 @@
#include <LPC17xx.h>
#include <stdbool.h>
/* ===================================================
* SMART MULTI-BASE CALCULATOR LPC1768
* Supports BIN, BASE4, OCT, DEC, HEX with
* keypad and LCD (no 7-segment).
*
* Features:
* SysTick 1 ms hardware timing
* HEX: double MODE press <2 s operator mode
* Signed decimal arithmetic; modular in other bases
* ===================================================
*/
/* ===== Pin & Mode Defines ===== */
#define COL_BASE 15
#define ROW_BASE 19
#define COL_MASK (0x0F << COL_BASE)
#define ROW_MASK (0x0F << ROW_BASE)
#define LCD_DATA_SHIFT 23
#define LCD_DATA_MASK (0x0F << LCD_DATA_SHIFT)
#define LCD_RS (1 << 27)
#define LCD_EN (1 << 28)
#define MODE_BUTTON (1 << 12)
/* Modes / Bases */
#define MODE_BIN 2
#define MODE_BASE4 4
#define MODE_OCT 8
#define MODE_DEC 10
#define MODE_HEX 16
/* Operators */
#define OP_NONE 0
#define OP_ADD 1
#define OP_SUB 2
#define OP_MUL 3
#define OP_CLR 4
#define OP_RES 5
/* ===== Globals ===== */
int input_num, stored_num, result;
unsigned int operation;
unsigned int current_base;
unsigned char hex_op_mode;
unsigned char result_displayed;
unsigned int key, last_key, stable;
unsigned int button_state, last_button_state, button_stable;
unsigned long last_mode_press_time;
/* ===== System tick counter ===== */
volatile unsigned long sys_millis = 0;
/* ===== Forward Declarations ===== */
void delay(volatile unsigned int d);
void lcd_delay(unsigned long r);
void lcd_write_nibble(unsigned char nibble, unsigned char is_data);
void lcd_cmd(unsigned char cmd);
void lcd_data(unsigned char data);
void lcd_init(void);
void lcd_print_str(const char *s);
void lcd_print_num(int num, unsigned int base);
void display_mode(void);
void display_input(void);
void display_result(void);
unsigned int scan_keypad(void);
unsigned int scan_mode_button(void);
unsigned int is_valid_digit(unsigned int key);
void change_mode(void);
void handle_mode_button(void);
void operate(unsigned int op);
void perform_operation(void);
unsigned char is_operator_active(unsigned int key);
int base_arith(int a, int b, unsigned int op, unsigned int base);
unsigned long millis(void);
/* =================================================== */
/* ===== Implementation */
/* =================================================== */
void delay(volatile unsigned int d){ while(d--) __NOP(); }
void lcd_delay(unsigned long r){ volatile unsigned long i; for(i=0;i<r;i++); }
/* ---- SysTick (1 ms) ---- */
void SysTick_Handler(void){ sys_millis++; }
unsigned long millis(void){ return sys_millis; }
/* ---- LCD primitives ---- */
void lcd_write_nibble(unsigned char nibble, unsigned char is_data){
unsigned long temp = (nibble & 0x0F) << LCD_DATA_SHIFT;
LPC_GPIO0->FIOPIN = (LPC_GPIO0->FIOPIN & ~LCD_DATA_MASK) | temp;
if(is_data) LPC_GPIO0->FIOSET = LCD_RS; else LPC_GPIO0->FIOCLR = LCD_RS;
LPC_GPIO0->FIOSET = LCD_EN; lcd_delay(100);
LPC_GPIO0->FIOCLR = LCD_EN; lcd_delay(250000);
}
void lcd_cmd(unsigned char c){ lcd_write_nibble(c>>4,0); lcd_write_nibble(c,0); }
void lcd_data(unsigned char d){ lcd_write_nibble(d>>4,1); lcd_write_nibble(d,1); }
void lcd_init(void){
lcd_delay(5000000);
lcd_write_nibble(0x03,0); lcd_delay(500000);
lcd_write_nibble(0x03,0); lcd_delay(500000);
lcd_write_nibble(0x03,0); lcd_delay(500000);
lcd_write_nibble(0x02,0); lcd_delay(500000);
lcd_cmd(0x28); lcd_cmd(0x0C); lcd_cmd(0x01); lcd_delay(500000); lcd_cmd(0x06);
}
void lcd_print_str(const char *s){ while(*s) lcd_data(*s++); }
void lcd_print_num(int num, unsigned int base){
char buf[17]; int i=0; unsigned int unum;
if(base==MODE_DEC && num<0){ lcd_data('-'); num=-num; }
unum=(unsigned int)num;
if(unum==0){ lcd_data('0'); return; }
while(unum>0 && i<16){
unsigned int d=unum%base;
buf[i++]=(d<10)?('0'+d):('A'+d-10);
unum/=base;
}
while(i>0) lcd_data(buf[--i]);
}
/* ---- Display helpers ---- */
void display_mode(void){
lcd_cmd(0x80);
lcd_print_str("Mode: ");
if(current_base==MODE_BIN) lcd_print_str("BIN ");
else if(current_base==MODE_BASE4) lcd_print_str("BASE4 ");
else if(current_base==MODE_OCT) lcd_print_str("OCT ");
else if(current_base==MODE_DEC) lcd_print_str("DEC ");
else { lcd_print_str("HEX");
if(hex_op_mode) lcd_print_str("[OPS]");
else lcd_print_str(" "); }
}
void display_input(void){
lcd_cmd(0xC0);
lcd_print_str("Input: ");
lcd_print_num(input_num,current_base);
lcd_print_str(" ");
}
void display_result(void){
lcd_cmd(0xC0);
lcd_print_str("Result: ");
lcd_print_num(result,current_base);
lcd_print_str(" ");
}
/* ---- Keypad scanning ---- */
unsigned int scan_keypad(void){
unsigned int col,row,row_bits;
for(col=0;col<4;col++){
LPC_GPIO0->FIOSET=COL_MASK; delay(50);
LPC_GPIO0->FIOCLR=(1<<(COL_BASE+col)); delay(200);
row_bits=(LPC_GPIO0->FIOPIN&ROW_MASK)>>ROW_BASE;
if(row_bits!=0x0F){
for(row=0;row<4;row++)
if(!(row_bits&(1<<row))){ LPC_GPIO0->FIOSET=COL_MASK; return col*4+row; }
}
}
LPC_GPIO0->FIOSET=COL_MASK;
return 0xFF;
}
/* ---- MODE button ---- */
unsigned int scan_mode_button(void){
return ((LPC_GPIO2->FIOPIN&MODE_BUTTON)==0)?1:0;
}
void change_mode(void){
if(current_base==MODE_DEC) current_base=MODE_BIN;
else if(current_base==MODE_BIN) current_base=MODE_BASE4;
else if(current_base==MODE_BASE4) current_base=MODE_OCT;
else if(current_base==MODE_OCT) current_base=MODE_HEX;
else current_base=MODE_DEC;
input_num=stored_num=result=0;
operation=OP_NONE; result_displayed=0;
display_mode(); display_input();
}
/* ---- Double-press / mode handler ---- */
void handle_mode_button(void){
unsigned long now=millis();
if(button_stable==3 && button_state==1){
if(current_base==MODE_HEX){
if((now-last_mode_press_time)<2000){
hex_op_mode=!hex_op_mode;
display_mode(); last_mode_press_time=0;
} else last_mode_press_time=now;
} else change_mode();
}
}
/* ---- Validation ---- */
unsigned int is_valid_digit(unsigned int key){
if(key>=16) return 0;
if(current_base==MODE_BIN && key>=2) return 0;
if(current_base==MODE_BASE4 && key>=4) return 0;
if(current_base==MODE_OCT && key>=8) return 0;
if(current_base==MODE_DEC && key>=10) return 0;
return 1;
}
/* ---- Arithmetic core ---- */
int base_arith(int a,int b,unsigned int op,unsigned int base){
int r=0;
switch(op){
case OP_ADD: r=a+b; break;
case OP_SUB: r=a-b; break;
case OP_MUL: r=a*b; break;
default: r=a; break;
}
if(base!=MODE_DEC){ /* wrap-around for others */
if(r<0) r=((r%base)+base)%base;
else r%= (base*base*base*base); /* loose limit */
}
return r;
}
/* ---- Operator control ---- */
void operate(unsigned int op){ stored_num=input_num; input_num=0; operation=op; result_displayed=0; }
void perform_operation(void){
result=base_arith(stored_num,input_num,operation,current_base);
display_result();
input_num=result; operation=OP_NONE; result_displayed=1;
}
unsigned char is_operator_active(unsigned int key){
if(key>=11 && key<=15){
if(current_base==MODE_HEX) return hex_op_mode;
else return 1;
}
return 0;
}
/* =================================================== */
/* ===================== MAIN ======================== */
/* =================================================== */
int main(void){
current_base=MODE_DEC;
input_num=stored_num=result=0;
operation=OP_NONE; result_displayed=0;
key=last_key=0xFF; stable=0;
button_stable=0; button_state=last_button_state=0;
hex_op_mode=0; last_mode_press_time=0;
SystemCoreClockUpdate();
SysTick_Config(SystemCoreClock/1000); // 1 ms tick
/* GPIO mux: make pins GPIO */
LPC_PINCON->PINSEL0=0; LPC_PINCON->PINSEL1=0;
LPC_PINCON->PINSEL3=0; LPC_PINCON->PINSEL4=0;
LPC_PINCON->PINSEL0 &= ~0xFFF00000; // P0.4P0.11 as GPIO
/* Directions: keypad columns out, rows in; LCD pins out; MODE button in */
LPC_GPIO0->FIODIR |= COL_MASK | LCD_DATA_MASK | LCD_RS | LCD_EN;
LPC_GPIO0->FIODIR &= ~ROW_MASK;
LPC_GPIO0->FIOSET = COL_MASK;
LPC_GPIO2->FIODIR &= ~MODE_BUTTON;
lcd_init(); display_mode(); display_input();
while(1){
key=scan_keypad();
button_state=scan_mode_button();
if(key==last_key) stable=(stable<5)?stable+1:stable;
else{ last_key=key; stable=0; }
if(button_state==last_button_state)
button_stable=(button_stable<5)?button_stable+1:button_stable;
else{ last_button_state=button_state; button_stable=0; }
handle_mode_button();
if(stable==3 && key!=0xFF){
if(is_operator_active(key)){
switch(key){
case 11: operate(OP_ADD); display_input(); break;
case 12: input_num=stored_num=result=0;
operation=OP_NONE; display_input(); break;
case 13: operate(OP_SUB); display_input(); break;
case 14: operate(OP_MUL); display_input(); break;
case 15: perform_operation(); break;
}
} else if(is_valid_digit(key)){
result_displayed=0;
input_num=input_num*current_base+key;
display_input();
}
stable=5;
}
/* Small idle delay; adjust as desired */
delay(3000);
}
}

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@ -90,6 +90,7 @@ void perform_operation(void);
unsigned char is_operator_active(unsigned int key); unsigned char is_operator_active(unsigned int key);
int base_arith(int a, int b, unsigned int op, unsigned int base); int base_arith(int a, int b, unsigned int op, unsigned int base);
unsigned long millis(void); unsigned long millis(void);
unsigned int segval = 0
/* =================================================== */ /* =================================================== */
/* ===== Implementation */ /* ===== Implementation */
@ -313,7 +314,7 @@ int main(void){
} }
/* ---- 7segment display (commonanode assumed) ---- */ /* ---- 7segment display (commonanode assumed) ---- */
unsigned int segval=seven_seg[0]; // default segval=seven_seg[0]; // default
if(current_base==MODE_BIN) segval=seven_seg[2]; if(current_base==MODE_BIN) segval=seven_seg[2];
else if(current_base==MODE_BASE4) segval=seven_seg[4]; else if(current_base==MODE_BASE4) segval=seven_seg[4];
else if(current_base==MODE_OCT) segval=seven_seg[8]; else if(current_base==MODE_OCT) segval=seven_seg[8];