The Serial Peripheral Interface (SPI)

Chapter 8

CML9S12-DP256

PIM_9DP256

Block Diagram

Table 8.1 68HC12 SPI0 Signals Pin SPI0 signal Name

PS4 MISO Master-In-Slave-Out PS5 MOSI Master-Out-Slave-In PS6 SCK Serial Clock PS7 SS Slave Select

7 6 5 4 3 2 1 0

SP0DR

MASTER

7 6 5 4 3 2 1 0

SP0DR

SLAVE

MOSI MOSIMISO MISO

SCK

SS SS

SCK

Table 8.2 SPI0 Registers in the 9S12DP256 Name Register Addr Description

SPI0CR1 00D8 SPI Control Register 1 SPI0CR2 00D9 SPI Control Register 2 SPI0BR 00DA SPI Baud Rate Register SPI0SR 00DB SPI Status Register SP0DR 00DD SPI Data Register

Table 8.2a SPI1 Registers in the 9S12DP256

Name Register Addr Description SPI1CR1 00F0 SPI Control Register 1 SPI1CR2 00F1 SPI Control Register 2 SPI1BR 00F2 SPI Baud Rate Register SPI1SR 00F3 SPI Status Register SP1DR 00F5 SPI Data Register

Table 8.2b SPI2 Registers in the 9S12DP256 Name Register Addr Description

SPI2CR1 00F8 SPI Control Register 1 SPI2CR2 00F9 SPI Control Register 2 SPI2BR 00FA SPI Baud Rate Register SPI2SR 00FB SPI Status Register SP2DR 00FD SPI Data Register

Liquid Crystal Display

2 3 4 5 6 7 9 101 8 11 12 13 14

16 x 1 Liquid Crystal Display

PJ2 (E)

PJ1 (R/W)

PJ0 (RS)VDD

Vo20K

PH0 (DB0)

PH1 (DB1)

PH2 (DB2)

PH3 (DB3)

PH4 (DB4)

PH5 (DB5)

PH6 (DB6)

PH7 (DB7)

RS R/W E

0 0

0 1

1 0

1

Operation

Write instruction code

Read busy flag and address counter

Write data

Read data1

Relationship between RS, R/W, and E

Table 7.4 HD44780 Instruction SetInstruction DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 Description

Clear display 0 0 0 0 0 0 0 1 Clears display & returns cursor to home.Sets I/D=1 in Entry Mode.

Return home 0 0 0 0 0 0 1 x Returns cursor to home position (Address 0)Set DD RAM address to zero.

Entry mode set 0 0 0 0 0 1 I/D S I/D=1: increment cursor; S=0: normal ;I/D=0: decrement cursor; S=1 shift display.

Display ON/OFFcontrol

0 0 0 0 1 D C B Sets ON/OFF all display (D), cursor (C),and blink of cursor (B).

Cursor or displayshift

0 0 0 1 S/C R/L x x S/C=1: display shift; S/C=0: cursor move;R/L=1: shift right; R/L=0: shift left.

Function set 0 0 1 DL N F x x DL=1: 8 bits; DL=0: 4 bits; N=1: 2 line;N=0: 1 line; F=1: 5x10 dots; F=0; 5x7 dots.

Set the CG RAMaddress

0 1 CG RAM address Sets the CG RAM address, after whichCG RAM data is sent and received.

Set the DD RAMaddress

1 DD RAM address Sets the DD RAM address, after whichDD RAM data is sent and received.

Read busy flag &address

BF Address counter Read busy flag (BF) and address countercontents.

CLM912-DP256LCD PORT4-bit SPIInterface

Write only

File: SPI0.WHP\ Serial Peripheral Interface SPI0HEX00D8 CONSTANT SPI0CR1 \ SPI Control Register 100D9 CONSTANT SPI0CR2 \ SPI Control Register 100DA CONSTANT SPI0BR \ SPI Baud Rate Register 00DB CONSTANT SPI0SR \ SPI Status Register 00DD CONSTANT SP0DR \ SPI Data Register : SPI.INIT ( -- ) \ Initialize SPI port

10 SPI0CR2 C! \ enable /SS00 SPI0BR C! \ 4 MHz (/2)52 SPI0CR1 C! ; \ CPHA = 0, CPO; = 0

 : ?SPI.DONE ( -- f ) \ Is SPI data sent?

7 SPI0SR ?HI ; : SEND.SPI ( c -- )

SP0DR C! \ send charBEGIN ?SPI.DONE \ wait till sentUNTILSP0DR C@ DROP ; \ clear SPIF

\ LCD for Axiom CML9S12-DP256load hex2asc.whpload string.whpload spi0.whp DECIMAL : 10ms.delay ( -- ) 7267 FOR NEXT ; : 20ms.delay ( -- ) 10ms.delay

10ms.delay ; : 50ms.delay ( -- ) 5 FOR 10ms.delay NEXT ; 

HEX\ Write 4-bit instruction: >instr4 ( n -- ) 0F AND

DUP send.spi \ EN LO, RS LODUP 80 OR \ EN HIsend.spisend.spi ; \ EN LO

 \ Write 8-bit instruction: >instr8 ( n -- )

DUP 4 RSHIFT>instr4>instr4 ;

 \ Write 4-bit data: >data4 ( c -- ) 0F AND

DUP 40 OR send.spi \ EN LO, RS HIDUP C0 OR send.spi \ EN HI40 OR send.spi ; \ EN LO

 \ Write 8-bit data: >data8 ( n -- )

DUP 4 RSHIFT>data4>data4 ;

\ Initialize 4-bit wide: lcd.init ( -- )

50ms.delay 3 >instr4 \ function set

50ms.delay 3 >instr4 \ function set

50ms.delay 3 >instr4 \ function set

50ms.delay 2 >instr4 \ function set

50ms.delay2C >instr8 \ 4-bits, 2 lines10ms.delay06 >instr8 \ inc cursor10ms.delay

0f >instr8 \ display on10ms.delay

01 >instr8 \ clear display20ms.delay

80 >instr8 \ set addr to 010ms.delay0 send.spi \ turn off all signals

0A BASE ! ; \ decimal default

: clear.lcd ( -- ) 1 >instr8 10ms.delay ; : hex>lcd ( hex -- ) HEX2ASC >data8 ; : type.lcd ( addr len -- ) ?DUP IF 0 DO DUP C@ >data8 10ms.delay 1+ LOOP THEN DROP ; : .lcd ( n -- ) (.) type.lcd ; : u.lcd ( u -- ) (u.) type.lcd ; DECIMAL