Improve CS for SPI bus to drive the boards please

[alejandroflamerich]

Every library that use a CS for drive a external device should call to a editable function in order to the users (we) can implement the best CS for our final proyect.

I mean if every library must call a function each time that want to set oir clr a CS instead of just set/clr a pin. It will improve our implementation.

Here a example of the function that I said:
/*************************************************
device : 1 : MMC
2 : Ethernet board
3: ....
...

status: 1 Select device
0 Unselect device
/**************************************************

void CS_Handler(unsigned char device, unsigned char state)
{
switch(device)
{
case MMC:
RB4_bit = status; // if I want to use a PIN as CS
break;

case Ethernet:
PORTD = 0x80; // if I want to select a device as a address
break;

case ........
........


}
}


This function allows the user to implement the best way ours CS's

Ing. Alejandro Flamerich

[anikolic]

Hi,
This is usually left to the user to implement it in his own way, according to his own affinities and programming practices. However, wish to thank you for your suggestions, I will inform our developers of your proposals, and inform you if they except your solution.

Best regards,
Aleksandar

[alejandroflamerich]

Hi Aleksandar.

Another important issue is how mikroC send data to SPI extra board and control the CS's. I had some troubles for implement TFTP.
I will ilustrate it with a simple example.

TFTP Protocol use FAT16 and Ethernet rutines at the same time.

unsigned int SPI_Ethernet_UserUDP(unsigned char *remoteHost, unsigned int remotePort, unsigned int destPort, unsigned int reqLength)
{
//NOTE here SPI_Ethernet_CS is active

//Now I need to read my MMC Card. Supous that I already open the file and everything
Mmc_Fat_Write(str,255); // this rutine active CS too.

//What happen with SPI bus when more than one CS is active. CS Ethernet and MMC
// Usually my MMC didnt have problem but when I try to send a UDP message again
yes I had problem

Spi_Ethernet_putByte(ch);
}

In conclusion would be well if you test the SPI rutine together with several SPI boards at the same time and improve the SPI drivers.

Best Regards.

Alejandro Flamerich