AN1833 Freescale Semiconductor / Motorola, AN1833 Datasheet - Page 31

• Manufacturer Part Number: AN1833
• Description: A Low-Power Wireless Remote Control Transmitter and Receiver
• Manufacturer: Freescale Semiconductor / Motorola

Code Listing
************************************************************************************
* Transmit Microcode for a Low Power Wireless Remote Control Unit
*
* Revision 7.1.98.2
* Grayhill Keypad
* Decode two keypad inputs, activate transmitter and send a message
*
* code is the first keypad input . command is the second keypad input
*
************************************************************************************
*** I/O Pin Equates:
serial_port
status_port
noise
frame
rxd
txd
xmt
BAUD_SEL
char
count
length
code
command
flag
************************************************************************************
* Start of Program Space
************************************************************************************
************************************************************************************
*Start - Initializes MCU hardware and enables interrupts.
************************************************************************************
Start:
KeyPdInt_Init:
AN1833
MOTOROLA
equ
equ
equ
equ
equ
equ
equ
equ
org
rmb
rmb
rmb
rmb
rmb
rmb
org
ldx
rsp
lda
sta
sta
300
$01
$00
4
5
0
4
5
$08
0c0
1
1
1
1
1
1
#$00
#$0
PORTA
DDRA
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For More Information On This Product,
Go to: www.freescale.com
; port used for serial port pins
; port used for driving LED's.
; pin # for noise LED
; pin # for frame LED
; pin # for receive data pin
; pin # for transmit data pin
; transmitter enable
; BAUD_SEL
; $04
; $08
; $10
; $20
; $40
; $80
; start of RAM space
; data register for sci
; temp storage variable
; preamble counter
; debounced key output storage #1
; debounced key output storage #2
; software flags
;
;
;
; reset stack pointer
; set port A register to all zeroes
;
; set Port A direction as Inputs
bit 0 - first key input done flag
4MHz osc
19.2k
9600
4800
2400
1200
600
2 MHz osc
1200
9600
4800
2400
Application Note
600
300
Code Listing
31
*
*
*