[SOLVED] AVR interrupt help (Serial receive)

jayanth.devarayanadurga · Dec 11, 2013

I am using ATMEGA16 and mikroC PRO AVR compiler. I need to know why serial reception using interrupts is not working. The UART transmit is working fine.

Code C - [expand]
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
// LCD module connections
sbit LCD_RS at PORTB2_bit;
sbit LCD_EN at PORTB3_bit;
sbit LCD_D4 at PORTB4_bit;
sbit LCD_D5 at PORTB5_bit;
sbit LCD_D6 at PORTB6_bit;
sbit LCD_D7 at PORTB7_bit;
 
sbit LCD_RS_Direction at DDB2_bit;
sbit LCD_EN_Direction at DDB3_bit;
sbit LCD_D4_Direction at DDB4_bit;
sbit LCD_D5_Direction at DDB5_bit;
sbit LCD_D6_Direction at DDB6_bit;
sbit LCD_D7_Direction at DDB7_bit;
// End LCD module connections
 
 
unsigned char ackPacket[64] = "";
unsigned int i = 0;
unsigned char processAck = 0, cmd = 0;
 
#define Lo(param) ((char *)&param)[0]
#define Hi(param) ((char *)&param)[1]
#define Higher(param) ((char *)&param)[2]
#define Highest(param) ((char *)&param)[3]
 
const unsigned int gheader = 0xEF01;
unsigned long goriginalModuleAddress = 0xFFFFFFFF;
unsigned long gnewModuleAddress = 0xAABBCCDD;
unsigned long gmoduleAddress = 0xFFFFFFFF;
unsigned long gchipAddress = 0xFFFFFFFF;
unsigned long int gpassword = 0xABCDEF01;
unsigned short gturnOnPort = 1, gturnOffPort = 0;
unsigned short gbufferID = 0, gpageNum2 = 0;
unsigned int gpageID = 0, gnoOfTemplates = 0, gstartPage = 0, gpageNum = 0;
unsigned char gdataContent[32] = "";
 
void UART1_Write_Byte(unsigned char byte){
         UART1_Write(byte);
}
 
unsigned int findChecksum(unsigned char PID, unsigned int pLen, unsigned char instructionCode){
 
          return (PID + pLen + instructionCode);
}
 
void cmd_GenerateImage(const unsigned int header, unsigned long int moduleAddress, unsigned char PID, unsigned int pLen, unsigned char instructionCode);
 
 
 
//Finger Print Processing Functions
//Generate Image
void cmd_GenerateImage(const unsigned int header, unsigned long int moduleAddress, unsigned char PID, unsigned int pLen, unsigned char instructionCode){
 
    UART1_Write_Byte(Hi(header));
    UART1_Write_Byte(Lo(header));
 
    UART1_Write_Byte(Highest(moduleAddress));
    UART1_Write_Byte(Higher(moduleAddress));
    UART1_Write_Byte(Hi(moduleAddress));
    UART1_Write_Byte(Lo(moduleAddress));
 
    UART1_Write_Byte(PID);
    UART1_Write_Byte(Hi(pLen));
    UART1_Write_Byte(Lo(pLen));
 
    UART1_Write_Byte(instructionCode);
 
    UART1_Write_Byte((findChecksum(PID, pLen, instructionCode) >> 8));
    UART1_Write_Byte((findChecksum(PID, pLen, instructionCode) & 0xFF));
 
}
 
 
void Interrupt(){
 
     if(RXC_bit){
 
         if(cmd == 7){
                ackPacket[i] = UDR;
                i++;
         }
 
         if(i == 10)processAck = 1;
 
     }
     
     RXC_bit = 0;
}
 
 
 
void main() {
 
     DDRB = 0xFF;
     PORTB = 0x00;
     DDRD = 0xFE;
     PORTD = 0x00;
     
     UART1_Init(57600);
     Delay_ms(2000);
     
     RXCIE_bit = 1;
 
     asm{
     
          sei
     
     }
     
     Lcd_Init();                        // Initialize LCD
     Lcd_Cmd(_LCD_CLEAR);               // Clear display
     Lcd_Cmd(_LCD_CURSOR_OFF);          // Cursor off
     Lcd_Out(1,1,"FP Scanner");                 // Write text in first row
 
 
     while(1){
     
           //Send some command to FP Scanner
            if(!processAck){
                    cmd = 7;
                    cmd_GenerateImage(gheader, gmoduleAddress, 0x01, 0x03, 0x01);
            }
            else if(processAck){
                    if(ackPacket[9] == 0x00)Lcd_Out(2,1,"Finger collection success");
                    else if(ackPacket[9] == 0x01)Lcd_Out(2,1,"Error when receiving Package");
                    else if(ackPacket[9] == 0x02)Lcd_Out(2,1,"Can't detect finger");
                    else if(ackPacket[9] == 0x03)Lcd_Out(2,1,"Fail to collect finger");
                    else if(ackPacket[0] == 'K')Lcd_Out(2,1,"Received...");
                    
                    processAck = 0;
                    i = 0;
                    cmd = 0;
            }
 
           Delay_ms(10000);
     
     }
}

Edit: The problem is solved. I used the mikroC PRO AVR interrupt assistant and it worked.

FvM · Dec 11, 2013

You'll notice that RXC bit is marked as readonly. It has to be always cleared by reading UDR. Exiting from ISR without reading UDR will cause a never ending ISR loop.

jayanth.devarayanadurga · Dec 11, 2013

My previous post updated.

Here is the working code.

Code C - [expand]
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
// LCD module connections
sbit LCD_RS at PORTB2_bit;
sbit LCD_EN at PORTB3_bit;
sbit LCD_D4 at PORTB4_bit;
sbit LCD_D5 at PORTB5_bit;
sbit LCD_D6 at PORTB6_bit;
sbit LCD_D7 at PORTB7_bit;
 
sbit LCD_RS_Direction at DDB2_bit;
sbit LCD_EN_Direction at DDB3_bit;
sbit LCD_D4_Direction at DDB4_bit;
sbit LCD_D5_Direction at DDB5_bit;
sbit LCD_D6_Direction at DDB6_bit;
sbit LCD_D7_Direction at DDB7_bit;
// End LCD module connections
 
 
unsigned char ackPacket[64] = "";
unsigned int i = 0;
unsigned char processAck = 0, cmd = 0;
 
#define Lo(param) ((char *)&param)[0]
#define Hi(param) ((char *)&param)[1]
#define Higher(param) ((char *)&param)[2]
#define Highest(param) ((char *)&param)[3]
 
const unsigned int gheader = 0xEF01;
unsigned long goriginalModuleAddress = 0xFFFFFFFF;
unsigned long gnewModuleAddress = 0xAABBCCDD;
unsigned long gmoduleAddress = 0xFFFFFFFF;
unsigned long gchipAddress = 0xFFFFFFFF;
unsigned long int gpassword = 0xABCDEF01;
unsigned short gturnOnPort = 1, gturnOffPort = 0;
unsigned short gbufferID = 0, gpageNum2 = 0;
unsigned int gpageID = 0, gnoOfTemplates = 0, gstartPage = 0, gpageNum = 0;
unsigned char gdataContent[32] = "";
 
void UART1_Write_Byte(unsigned char byte){
         UART1_Write(byte);
}
 
unsigned int findChecksum(unsigned char PID, unsigned int pLen, unsigned char instructionCode){
 
          return (PID + pLen + instructionCode);
}
 
void cmd_GenerateImage(const unsigned int header, unsigned long int moduleAddress, unsigned char PID, unsigned int pLen, unsigned char instructionCode);
 
 
 
//Finger Print Processing Functions
//Generate Image
void cmd_GenerateImage(const unsigned int header, unsigned long int moduleAddress, unsigned char PID, unsigned int pLen, unsigned char instructionCode){
 
    UART1_Write_Byte(Hi(header));
    UART1_Write_Byte(Lo(header));
 
    UART1_Write_Byte(Highest(moduleAddress));
    UART1_Write_Byte(Higher(moduleAddress));
    UART1_Write_Byte(Hi(moduleAddress));
    UART1_Write_Byte(Lo(moduleAddress));
 
    UART1_Write_Byte(PID);
    UART1_Write_Byte(Hi(pLen));
    UART1_Write_Byte(Lo(pLen));
 
    UART1_Write_Byte(instructionCode);
 
    UART1_Write_Byte((findChecksum(PID, pLen, instructionCode) >> 8));
    UART1_Write_Byte((findChecksum(PID, pLen, instructionCode) & 0xFF));
 
}
 
void UART1_Interrupt() iv IVT_ADDR_USART_RXC ics ICS_AUTO {
 
      if(cmd == 7){
                ackPacket[i] = UDR;
                i++;
      }
 
      if(i == 10)processAck = 1;
 
      RXC_bit = 0;
}
 
void main() {
 
     DDRB = 0xFF;
     PORTB = 0x00;
     DDRD = 0xFE;
     PORTD = 0x00;
     
     UART1_Init(57600);
     Delay_ms(2000);
     
     RXCIE_bit = 1;
 
     asm{
         sei
     }
     
     Lcd_Init();                        // Initialize LCD
     Lcd_Cmd(_LCD_CLEAR);               // Clear display
     Lcd_Cmd(_LCD_CURSOR_OFF);          // Cursor off
     Lcd_Out(1,1,"FP Scanner");                 // Write text in first row
 
 
     while(1){
     
            //Send some command to FP Scanner
            if(!processAck){
                    cmd = 7;
                    cmd_GenerateImage(gheader, gmoduleAddress, 0x01, 0x03, 0x01);
            }
            else if(processAck){
                    if(ackPacket[9] == 0x00){
                            Lcd_Out(2,1,"Finger collection   ");
                            Lcd_Out(3,1,"success             ");
                    }
                    else if(ackPacket[9] == 0x01){
                            Lcd_Out(2,1,"Error when receiving");
                            Lcd_Out(3,1,"Package             ");
                    }
                    else if(ackPacket[9] == 0x02){
                            Lcd_Out(2,1,"Can't detect finger ");
                    }
                    else if(ackPacket[9] == 0x03){
                            Lcd_Out(2,1,"Fail to collect     ");
                            Lcd_Out(3,1,"finger              ");
                    }
 
                    processAck = 0;
                    i = 0;
                    cmd = 0;
            }
 
           Delay_ms(5000);
     
     }
}

[SOLVED] AVR interrupt help (Serial receive)

jayanth.devarayanadurga

Banned

FvM

Super Moderator

jayanth.devarayanadurga

jayanth.devarayanadurga

Banned

Attachments

Similar threads

[SOLVED] AVR interrupt help (Serial receive)

jayanth.devarayanadurga

Banned

FvM

Super Moderator

jayanth.devarayanadurga

Banned

Attachments

Similar threads

Privacy & Transparency

Privacy & Transparency