(* USART-0/1 SPI on P3 or P5 of MSP430F149
Function P1 P2 P3 P4 P5 P6 Lable name
-------------------------------------------------------------
Input 20 28 18 1C 30 34 PxIN
Output 21 29 19 1D 31 35 PxOUT
Direction 22 2A 1A 1E 32 36 PxDIR
Intrpt flag 23 2B 1B 1F -- -- PxIFG
Intrpt edge 24 2C -- -- -- -- PxIES
Intrpt on/off 25 2D -- -- -- -- PxIE
Select 26 2E -- -- 33 37 PxSEL
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P3.0/P5.0 - CS 01 \ SPI enable low x1=Chip select
P3.1/P5.1 - MOSI 02 \ Data bitstream out x0=Master in
P3.2/P5.2 - MISO 04 \ Data bitstream in x1=Master out
P3.3/P5.3 - CLK 08 \ Clock x1=Clock
More SPI info on page 444ff of SLAU144J.PDF
Configuration of the pins on page 129ff of SLAU049.PDF
USART - Ucontrol - Tcontrol - Rcontrol - Mcontrol - B0 - B1 - RB - TB
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0 70 71 72 73 74 75 76 77
1 78 79 7A 7B 7C 7D 7E 7F
*)
( UART-0/1 SPI interface )
hex
v: fresh
: SPI} ( -- ) 1 31 *bis ; \ P5OUT SPI off CS=high
: {SPI ( -- ) 1 31 *bic ; \ P5OUT SPI on, CS=low
: SPI-ON ( -- )
0B 32 c! \ P5DIR Outputs P5.0, P5.2, P5.3 & P5.1 input
0E 33 *bis \ P5SEL SPI out is P5.2, P5.3 & P5.1 input
10 05 *bis \ ME2 Enable SPI1
1 78 *bis \ UCTL21 Reset USART
17 78 c! \ UCTL1 SPI mode on, Master mode, 8 -bit wide
32 79 *bis \ UTCTL1 3-wire mode, SMCLK, Clk low, Normal
4 7C c! \ UBR10 Clock is 8Mhz/4 = 2MHz
0 7D c! \ UBR11
0 7B c! \ UMCTL1 Not used must be zero!
1 78 *bic \ UCB1CTL1 Free USCI
spi} ; \ CS = 1
code SPI-I/O ( b1 -- b2 ) \ Read and write at SPI-bus
tos 7F & .b mov \ UTXBUF1, write
begin, 10 # 3 & .b bit \ IFG2.4
cs? until,
7E & tos .b mov \ URXBUF1, read
next
end-code
: SPI-OUT ( b -- ) spi-i/o drop ; \ Write b to SPI-bus
: SPI-IN ( -- b ) 0 spi-i/o ; \ Read b from SPI
\ : TEST ( -- )
\ spi-on 8 78 *bis 0 \ Activate SPI with internal feedback
\ begin
\ spi-i/o dup . \ Send & receive, show result
\ 1+ 100 ms \ Increase data & wait
\ key? until
\ 8 78 *bic ; \ Remove internal feedback
spi-on
v: fresh
shield spi\ freeze