While trying to interface flash SST25VF512 with AT80c51, i find difficulty in Byte program mode of writing to flash.
This is the code i used, could somebody who has worked on this please help me out,
void main(void){ ce = 1; SCK = 0; TMOD = 0x20; TH1 = -3; // 9600 baud SCON = 0x50; TR1 = 1; TI = 1; addr = 0x00000012; Rd_ID = Read_ID(); Byte_Program(addr); void Byte_Program(unsigned long addr){ ce = 0; E_WRSR(); WREN(); Send_Byte(0x02); // Byte Program CMD Send_Byte(((addr & 0xFFFFFF) >> 16)); // sending 3 address bytes Send_Byte(((addr & 0xFFFF) >> 8)); Send_Byte(addr & 0xFF); Send_Byte(0x10); //send data SR_byte = Read_Status_Register(); while((SR_byte &0x01) != 0x00){ SR_byte = Read_Status_Register(); } ce = 1; } void E_WRSR(){ ce = 0; Send_Byte(0x50); // enable Status Reg ce = 1; ce = 0; Send_Byte(0x01); // select write to status register Send_Byte(0x00); // mode 0, ce = 1; } void WREN(){ ce = 0; Send_Byte(0x06);// to Write enable ce = 1; } unsigned char Get_Byte(){ unsigned char i=0, in=0, temp=0; for(i=0;i<8;i++){ in = (in << 1); temp = SO; SCK = 1; if (temp == 1){ in = in | 0x01; } SCK = 0; } return in; } void Send_Byte(unsigned char b_out){ for(i=0;i<8;i++){ if((b_out & 0x80) == 0x80) si = 1; else si = 0; SCK = 1; b_out = (b_out << 1); SCK = 0; } }
Thanks in advance,
clocking 8051, you mean baud rate that is set to 9600, smod is mode 0, so, not doubled,
i think its 12 clocker
We divide crystal frequency by 12 and then further by 16 or 32 depending on smod
If that is it, then its 12 clocker, Is it right?
"clocking 8051, you mean baud rate"
No.
The CPU clock is the crystal fequency, or the frequency of whatever clock source you use instead of a crystal. This is what clocks the CPU - hence the term, "CPU Clock"
Ok, since i am doing it manually to clock the flash thru SCK. I believe 8051 uses the internal crystal to execute through the program. that is 11.0592 MHz