AVRASM ver. 1.57 C:\Documents and Settings\Max\My Documents\EEL5666 IMDL\CommandRegRead\CommandRegRead.asm Wed Jul 02 23:16:38 2003 ;----------------------------------------------------------------- ; Name: 128 TWI.asm ; Description: ATMega128 Two Wire Interface (IC2) Test Program ; Interfaces SRF09 Sonar Range Finder to IC2 Bus ; Author: Max Koessick ; Class: EEL5666C, Intelligent Machine Design Lab ; Date: June 28, 2003 ; Revision 1.a ; Changes to Date: ; 6/28/03 First Revision ;----------------------------------------------------------------- .nolist ; Do not include in .lst file ; Interrupt service vectors .org $0000 000000 c000 rjmp Reset ; Reset vector ;.org INT0addr ; rjmp IntV0 ; INT0 vector (ext. interrupt from pin D0) ;.org INT1addr ; rjmp IntV1 ; INT1 vector (ext. interrupt from pin D1) ;.org INT2addr ; rjmp IntV2 ; INT2 vector (ext. interrupt from pin D2) ;----------------------------------------------------------------- ; Register defines for main loop ;----------------------------------------------------------------- .def mpr =r16 ; defines multipurpose register .def mpr2 =r17 ; multipurpose register 2 .def ECHOL =r18 .def ECHOH =r19 .def ErrorReg=r20 .def mpr3 =r21 ; Equate statements .equ start = $08 ; Start Condition .equ Rep_start = $10 ; Repeated Start Condition Message .equ MT_SLA_ACK = $18 ; Master Transmitter Slave Address Acknowledge .equ MT_DATA_ACK = $28 ; Master Transmitter Data Acknowledge .equ MT_DATA_NACK= $30 ; Master Transmitter Data Not Acknowledge .equ MR_SLA_ACK = $40 ; Master Receiver Slave Address Acknowledge .equ MR_SLA_NACK = $48 ; Master Receiver Slave Address Acknowledge .equ MR_DATA_ACK = $50 ; Master Receiver Data Acknowlede .equ MR_DATA_NACK= $58 ; Master Receiver Data Not Acknowledge .equ W = 0 ; Write Bit .equ R = 1 ; Read Bit .equ SLA = $E0 ; Slave Address of Sonar Ranger SRF08 .equ Inches = $50 ; Return result in Inches .equ CommandReg = $00 ; SRF08 Command Register ;----------------------------------------------------------------- ; Reset vector ;----------------------------------------------------------------- Reset: ;-----Setting Stackpointer---------------------------------------- 000001 ef0f ldi MPR,low(RAMEND) ; Set stackptr to ram end 000002 bf0d out SPL,MPR 000003 e100 ldi MPR, high(RAMEND) 000004 bf0e out SPH, MPR ;-----Set Port Directions----------------------------------------- 000005 ef0f ser mpr ; Set TEMP to $FF to... 000006 bb04 out DDRC,mpr 000007 ef0f ser mpr 000008 bb05 out PORTC,mpr ; Lights off 000009 e001 ldi mpr,$01 00000a bb01 out DDRD,mpr ;Set PD0 as output and PD1 as input 00000b e001 ldi mpr,(1<