Code Body

To use this file copy and paste this: // #URL-lib "http://pin1.org/forthlib/flb/General/SPI.flb" into BV Terminal 3 or here to download.

// REQUIRES: // #URL-lib "http://pin1.org/forthlib/flb/General/soft1.flb" // #URL-lib "http://pin1.org/forthlib/flb/General/pinsel.flb"

// CONSTANTS: // SPI registers &E0020000 constant S0SPCR // config &E0020004 constant S0SPSR // status &E0020008 constant S0SPDR // data &E002000C constant S0SPCCR // clock &E002001C constant S0SPINT variable inital

Full Contents of File

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// SPI - This is the basic interface for SPI which has a very simple
// method of working. There is a data in, data out and chip select
// when data is going in, data is also comming out so if just data out is
// wanted then a dummy data in is sent.
// CS is hardware / device dependant and can be any port set to o/p normally
// a high hill select the device

// REQUIRES:
// #URL-lib "http://pin1.org/forthlib/flb/General/soft1.flb"
// #URL-lib "http://pin1.org/forthlib/flb/General/pinsel.flb"

// SPI - This is the basic low level card access

// CONSTANTS:
// SPI registers
&E 0 0 2 0 0 0 0 c o n s t a n t S 0 S P C R // config
&E 0 0 2 0 0 0 4 c o n s t a n t S 0 S P S R // status
&E 0 0 2 0 0 0 8 c o n s t a n t S 0 S P D R // data
&E 0 0 2 0 0 0 C c o n s t a n t S 0 S P C C R // clock
&E 0 0 2 0 0 1 C c o n s t a n t S 0 S P I N T
v a r i a b l e i n i t a l

// sets spi speed
: set-speed ( speedHz --- ) // must be > 8 and even number
p c l k s w a p / 8 max &fe and S0SPCCR !
-1 i n i t a l !
;
// testing only
// : y S0SPSR @ ph. ;

// Hardest part of spi is getting the configuration correct
// CPOL, CPHA and MSB or LSB first need setting correctly
: init
&2 0 S 0 S P C R ! // master CPOL & CPHA = 0
i n i t a l @ 0 = i f 2 5 4 S 0 S P C C R ! t h e n // default slow
4 1 p i n s e l e c t // SCK function 1 for SPI
5 1 p i n s e l e c t // MISO
6 1 p i n s e l e c t // MOSI
;

// -*-*-*-*-*-*-*- P U B L I C *-*-*-*-*-*-*-*-*-*-*-*-*-*-*
// This is all there is, it clocks in and out at the same
// time n1 is the byte to clock in and n2 is what is fetched
// from the device so when writing drop n2
// ( n1 --- n2)
: <0>spi
// inital @ 0= if init -1 inital ! then // remove check for more speed
S 0 S P D R !
0
1 0 0 f o r
S 0 S P S R @ &8 0 a n d
i f d r o p -1 l e a v e t h e n
n e x t
i f
S 0 S P D R @
e l s e
." S P I p r o b l e m " a b o r t
t h e n
;
: <0>spi.init i n i t ;
: <0>spi.speed ( Hz --- ) s e t -s p e e d ;