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Re: Using SPI hardware
Hi,
@ Henrik
On another computer (real RS232 port) = same result
@Archangel
Hi and thank you for your reply
Do you think I forgot something in config bit ?
I'm not expert... May be you can check my config bits:
Maybe I can try at 16MHz, but I choose this pic because of 64MHz.
Regards
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Re: Using SPI hardware
Hi,
I had never used the MSSP module in slave mode Before but I just had a play with two 18F25K20 devices, one as master and one as slave.
The master sends the letters "A" to "Z" and outputs both what it sends and what it recieves to the serial terminal.
The slave responds with the letters "Z" to "A". It outputs what it receives and what it sends to the serial terminal.
At this time I did not have time to implement and test the SS-line but apart from that it appears to work as expected.
You might be able to gain some insight into your trouble by looking at these two programs.
Here's the code for the master:And here's the code for the slave:Code:'**************************************************************** '* Name : SPI Master.pbp * '* Author : Henrik Olsson * '* Notice : Copyright (c) 2013 [Henrik Olsson] * '* : All Rights Reserved * '* Date : 2013-11-12 * '* Version : 1.0 * '* Notes : Designed to run on 18F45K20, AMICUS18 platform. * '* : * '**************************************************************** DEFINE OSC 64 ' Default oscillator speed on the AMICUS18 is 16*4MHz DEFINE LOADER_USED 1 ' We're using a bootloader. DEFINE HSER_RCSTA 90h ' Enable serial port & continuous receive DEFINE HSER_TXSTA 24h ' Enable transmit, BRGH = 1 DEFINE HSER_CLROERR 1 ' Clear overflow automatically DEFINE HSER_SPBRG 138 ' 115200 Baud @ 64MHz, -0,08% SPBRGH = 0 BAUDCON.3 = 1 ' Enable 16 bit baudrate generator TRISC = %10010110 ' RX, TX, SDO, SDI, SCK, N/U, N/U, CS TRISB = %11111111 ' N/U, N/U, N/U, N/U, N/U, N/U, N/U, N/U ' Aliases for the MSSP module status and control bits. SSPEN VAR SSPCON1.5 ' SSP Enable bit CKP VAR SSPCON1.4 ' Clock Polarity Select SMP VAR SSPSTAT.7 ' Data input sample phase CKE VAR SSPSTAT.6 ' Clock Edge Select bit BF VAR SSPSTAT.0 ' Buffer full flag. ' Set up the MSSP module. CKP = 0 ' Clock idles low CKE = 0 ' Transmit on idle to active transition. SMP = 0 ' Sample in middle of data SSPEN = 1 ' Enable SPI pins SSPCON1.0 = 1 ' Slow down SPI clock to Fosc/16 for now. i VAR BYTE Response VAR BYTE Response = SSPBUF ' Dummy read to buffer and BF-flag HSEROUT ["Master start...", 13] HSEROUT ["TX - RX",13] Pause 5000 Main: For i = "A" to "Z" ' Send letters A to Z SSPBUF = i ' Load buffer with content While BF = 0 : WEND ' Wait for operation to complete Response = SSPBUF ' Read response HSEROUT [i, " - ", Response, 13] PAUSE 10 NEXT HSEROUT ["Done.....", 13] Pause 5000 Goto Main/Henrik.Code:'**************************************************************** '* Name : SPI Slave.pbp * '* Author : Henrik Olsson * '* Notice : Copyright (c) 2013 [Henrik Olsson] * '* : All Rights Reserved * '* Date : 2013-11-12 * '* Version : 1.0 * '* Notes : Designed to run on 18F45K20, AMICUS18 platform. * '* : * '**************************************************************** DEFINE OSC 64 ' Default oscillator speed on the AMICUS18 is 16*4MHz DEFINE LOADER_USED 1 ' We're using a bootloader. DEFINE HSER_RCSTA 90h ' Enable serial port & continuous receive DEFINE HSER_TXSTA 24h ' Enable transmit, BRGH = 1 DEFINE HSER_CLROERR 1 ' Clear overflow automatically DEFINE HSER_SPBRG 138 ' 115200 Baud @ 64MHz, -0,08% SPBRGH = 0 BAUDCON.3 = 1 ' Enable 16 bit baudrate generator TRISC = %10011111 ' RX, TX, SDO, SDI, SCK, N/U, N/U, CS TRISB = %11111111 ' N/U, N/U, N/U, N/U, N/U, N/U, N/U, N/U ' Aliases for the MSSP module status and control bits. SSPEN VAR SSPCON1.5 ' SSP Enable bit CKP VAR SSPCON1.4 ' Clock Polarity Select SMP VAR SSPSTAT.7 ' Data input sample phase CKE VAR SSPSTAT.6 ' Clock Edge Select bit BF VAR SSPSTAT.0 ' Buffer Full bit ' Set up the MSSP module. CKP = 0 ' Clock idles low CKE = 0 ' Transmit on idle to active transition. SMP = 0 ' Sample in middle of data While PortC.4 = 1 : WEND ' Wait for SCK pin to be idle before enabling MSSP SSPCON1 = %00100101 ' Slave mode, no SS i VAR BYTE Response VAR BYTE HSEROUT ["Slave start...", 13] HSEROUT ["RX - TX", 13] Main: For i = "Z" to "A" STEP -1 SSPBUF = i ' Load buffer While BF = 0 : WEND ' Wait for data to arrive Response = SSPBUF ' Read data from buffer, clears flag. HSEROUT [Response, " - ", i, 13] NEXT HSEROUT ["Done...",13] Goto Main
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Re: Using SPI hardware
Hello again,
Looking at the slave code in post #3 above it saysThe setting and comment does not match, Setting the CKE bit makes the slave, in this case, output data on active to idle state of the clock. But, looking at the master code it is set up to sample the data in the middle of the cycle. I'm not sure if this is the actual problem but comparing it to my examples it's something that differs.Code:CKE = 1 ' transmit on idle to active transition
/Henrik.
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Re: Using SPI hardware
Dear Henrik, and other who tryed to help me.
Today I made a new prototype.. Soldering new components on a new (but same) professionnal dual layer PCB and, using same programs
Plugin and.... Working !
I really don't know what's wrong with the first one.
My new prototype has just what is needed to test the SPI. (Only 2 pic and max232a)
Trying now to write the complete program... God bless me
Thank you very much
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