I am into a project where I need 2 establish communication between ADuc814(Master) and ADuc841(Slave). Master shud Receive data transmitted by Slave. I am unable to establish the comm. I feel there is no response 4rm slave as though master generates the clock and SS pin is low, slave does not response. Is it necessary that both master and slave should operate in same CLOCK?? For Hardware connection, MOSI, MISO, SCLK and SS pins of Master and Slave are connected. Foll is the code Master Code
#include <ADUC814.H> unsigned char Data[20]; //Store SPI Rx data in Memory void Uart_Tx(unsigned char AsciData); //Serial Tx sbit SS = 0xB5; void main() { char i; PLLCON = 0x00; //Core Clk = 16.6777MHz //////////baud 0f 4800//////// RCAP2H = -1; RCAP2L = 0x92; TH2 = -1; TL2 = 0x92; SCON = 0x50; T2CON = 0x34; ////////////////////////////// CFG814 = 0x01; // Enable P3.5,6,7 for SPI SPICON = 0x37; // Master, CPOH=1,CPOL=0 SS = 0; // Slave Select Enable for(i=0;i<20;i++) { SPIDAT = 0x00; // SPI Clock Generate while(!ISPI); ISPI = 0; Data[i] = (unsigned char)SPIDAT; } /////////Serial Tx SPI Data into UART////////// for(i=0;i<20;i++) { Uart_Tx(Data[i]); Uart_Tx('\n'); } ///////////////////////////////////////////// }
Slave Code, ADuC841
void main() { char i; SPICON = 0x24; // Slave, CPOH=1, CPOL=0 for(i=0;i<20;i++) { SPIDAT = 0x38; /*Transmit Dummy Data, Asci of '8' while(!ISPI); ISPI = 0; } }
Friendzzzz Please Help.........
Although this might not be what your problem is, you might as well eliminate it as a potential source...
You said "Even SS pin is low throughout" so does that mean it is always low like it is shown in your 'master' code?
I recommend that you insert the SS appropriately between byte transfers. The data-sheet on the ADuC814 indicates that the SS line should be low 'during the byte communication.' (The implication being that it was and/or should return to high otherwise).
If there is a timing issue, the SS line might be used to reset (or re-initialize) the internal state-machine associated with the bit-level transfers.
#include <ADUC814.H> unsigned char Data[20]; //Store SPI Rx data in Memory void Uart_Tx(unsigned char AsciData); //Serial Tx sbit SS = 0xB5; void main() { char i; PLLCON = 0x00; //Core Clk = 16.6777MHz //////////baud 0f 4800//////// RCAP2H = -1; RCAP2L = 0x92; TH2 = -1; TL2 = 0x92; SCON = 0x50; T2CON = 0x34; ////////////////////////////// CFG814 = 0x01; // Enable P3.5,6,7 for SPI SPICON = 0x37; // Master, CPOH=1,CPOL=0 SS = 1; // Slave Select Disable // <===== Alter to 1 for(i=0;i<20;i++) { SS = 0; // Slave Select Enable // <===== ADD SPIDAT = 0x00; // SPI Clock Generate while(!ISPI); ISPI = 0; SS = 1; // Slave Select Disable// <===== ADD Data[i] = (unsigned char)SPIDAT; } /////////Serial Tx SPI Data into UART////////// for(i=0;i<20;i++) { Uart_Tx(Data[i]); Uart_Tx('\n'); } ///////////////////////////////////////////// }
BUT
CodwArchitect for the NXP lpc chips (free from http://www.esacademy.com ) work just fine for the SILabs derivatives (after 5 minutes of work).
Whether you want to/can use the code from CodeArchitect with your chips or not, have a look, it will give you some guidelines.
Erik