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This program reads a number pressed on the personal computers keyboard while using a terminal program and displays the number on the 7 segment display.

The signals used for this example are listed below:
{| border="1" cellpadding="5" cellspacing="2" align="center" style="text-align: center;"
|+ align="bottom"|'''Signals Used and Connector Locations for Example 06-03'''
|'''Signal'''
|'''LPC4330 PIN NAME'''
|'''BAM210E'''
|'''BAM210'''
|'''BAM200E'''
|'''BAM200'''
|'''Used for'''
|-
|USBTX
|P2_10
|MBED-HDK
|MBED-HDK
|S10-4
|n/p
|MBED-HDK Serial RX 
|-
|USBRX
|P2_11
|MBED-HDK
|MBED-HDK
|s10-5
|n/p
|MBED-HDK Serial TX 
|- 
|D0
|P6_5
|J9-1
|J9-1
|S2-5
|S2-5
|Ones Segment A
|- 
|D1
|P6_4
|J9-2
|J9-2
|S2-4
|S2-4
|Ones Segment B
|- 
|D2
|P1_7
|J9-3
|J9-3
|S3-7
|S3-7
|Ones Segment C
|- 
|D3
|P4_0
|J9-3
|J9-3
|S3-7
|S3-7
|Ones Segment D
|- 
|D4
|P6_9
|J9-4
|J9-4
|S8-7
|n/p
|Ones Segment E
|- 
|D5
|P5_5
|J9-5
|J9-5
|S3-8
|S3-8
|Ones Segment F
|- 
|D6
|P5_7
|J9-6
|J9-6
|S3-9
|S3-9
|Ones Segment G
|- 
|D7
|P7_6
|J9-7
|J9-7
|S4-6
|S4-6
|Ones Segment DP
|- 
|D8
|P6_12
|J10-1
|J10-1
|S10-3
|n/p
|Tens Segment A
|- 
|D9
|P5_0
|J10-2
|J10-2
|S1-4
|S1-4
|Tens Segment B
|- 
|D10
|P4_6
|J10-3
|J10-3
|S2-3
|S2-6
|Tens Segment C
|- 
|D11
|P4_8
|J10-4
|J10-4
|S2-7
|S2-7
|Tens Segment D
|- 
|D12
|P4_9
|J10-5
|J10-5
|S2-8
|S2-8
|Tens Segment E
|- 
|D13
|P4_10
|J10-6
|J10-6
|S2-9
|S2-9
|Tens Segment F
|- 
|D16
|P2_3
|J10-9
|J10-9
|S4-8
|S4-8
|Tens Segment G
|- 
|D17
|P2_4
|J10-10
|J10-10
|S4-9
|S4-9
|Tens Segment DP
|- 
|}

The following schematic can be used to build the circuit with a BAM210E or BAM210.
[[Image:BAM210_06_02_SCH.png|center|alt=BAM210|frame|<div align="center">'''Schematic for example 06-03''']]

<div style="text-align: left;">
 /* Program Example 6.3: Host keypress to 7-seg display
                                                               */
 #include "mbed.h"
 Serial pc(USBTX, USBRX);                         // comms to host PC
 BusOut Seg1(D0,D1,D2,D3,D4,D5,D6,D7);            // A,B,C,D,E,F,G,DP
 BusOut Seg2(D8,D9,D10,D11,D12,D13,D16,D17);      // A,B,C,D,E,F,G,DP
 
 void SegInit(void);                          // function prototype
 void HostInit(void);                         // function prototype
 char GetKeyInput(void);                      // function prototype
 char SegConvert(char SegValue);              // function prototype
 char data1, data2;                           // variable declarations
 
 int main() {         // main program
   SegInit();         // call function to initialise the 7-seg displays
   HostInit();        // call function to initialise the host terminal
   while (1) {                 // infinite loop
     data2 = GetKeyInput();    // call function to get 1st key press
     Seg2=SegConvert(data2);   // call function to convert and output
     data1 = GetKeyInput();    // call function to get 2nd key press
     Seg1=SegConvert(data1);   // call function to convert and output
     pc.printf("  ");          // display spaces between numbers
   }
 }
 // functions
 void SegInit(void) {
   Seg1=SegConvert(0);        // initialise to zero
   Seg2=SegConvert(0);        // initialise to zero
 }
 
 void HostInit(void) {
   pc.printf("\n\rType two digit numbers to be displayed\n\r");
 }
 
 char GetKeyInput(void) {
   char c = pc.getc();      // get keyboard data (ascii 0x30-0x39)
   pc.printf("%c",c);       // print ascii value to host PC terminal
   return (c&0x0F);         // apply bit mask to convert to decimal, and return
 }
 
 char SegConvert(char SegValue) {        // function 'SegConvert'
   char SegByte=0x00;
   switch (SegValue) {                   //DP G F E D C B A
     case 0 : SegByte = 0x3F;break;      // 0 0 1 1 1 1 1 1 binary
     case 1 : SegByte = 0x06;break;      // 0 0 0 0 0 1 1 0 binary
     case 2 : SegByte = 0x5B;break;      // 0 1 0 1 1 0 1 1 binary
     case 3 : SegByte = 0x4F;break;      // 0 1 0 0 1 1 1 1 binary
     case 4 : SegByte = 0x66;break;      // 0 1 1 0 0 1 1 0 binary
     case 5 : SegByte = 0x6D;break;      // 0 1 1 0 1 1 0 1 binary
     case 6 : SegByte = 0x7D;break;      // 0 1 1 1 1 1 0 1 binary
     case 7 : SegByte = 0x07;break;      // 0 0 0 0 0 1 1 1 binary
     case 8 : SegByte = 0x7F;break;      // 0 1 1 1 1 1 1 1 binary
     case 9 : SegByte = 0x6F;break;      // 0 1 1 0 1 1 1 1 binary
   }
     return SegByte;
 }

The terminal window was captured in the image below.
[[Image:BAM210_06_03_TERM.png|center|]]

The following image shows the built circuit on a BAM210E.
[[Image:BAM210_TwoDigitCounter.jpeg|center|]]