MBP28
From Curuxa
Intermediate complexity Main Board built on a perforated board using a Microchip PIC microcontroller.
Contents |
Features
- Based on a PIC16F722
- 28 pin
- Power supply: 1.8 to 5.5V
- Program memory: 3584 bytes (2048 instructions)
- RAM: 128 bytes
- 62.5kHz-16MHz internal oscillator
- Up to 20MHz external oscillator
- Two 8-bit timers. One 16-bit timer
- 2x CPP/PWM
- 8-bit, 11-channel Analog-to-Digital Converter
- SPP (SPI, slave I2C, master I2C must be implemented in software)
- AUSART
- Capacitive sensing module
- ICSP connector
- Up to 25 data input/outputs
- I2C connector with pull-ups
- Two decoupling capacitors
Electronic circuit
Bill of materials:
- Perforated board of at least 10x21 holes. Individual pads, not copper strips
- 1x PIC16F722-I/P or PIC16F722-E/P
- 1x 28-pin PDIP socket
- 2x 10k, 1/4W resistors
- 6x Right-angle male headers (usually sold as 40-pin strips)
- 79x Straight male headers (usually sold as 40-pin strips) (you can also buy double-row strips)
- 1x 100uF electrolytic capacitor
- 1x 100nF ceramic capacitor
- Some thin wire
 |  |
Printable version: Single, Double
Optional parts
Both decoupling capacitors can usually be left out of the board, but it's not recommended. They stabilize the voltage from the power supply and filter small voltage peaks/drops. Capacitive or inductive loads such as motors require decoupling capacitors.
The I2C connector, R1 and R2 resistors can also be avoided when you are certain you won't be using I2C.
Construction
Test
C
PIC16F722 is not supported by SDCC yet.
Assembly language
The following code can be assembled using gputils/gpasm.
;=================================================================== ; Sample program for MBP28 using a PIC16F722 ; ; This program configures all available pins as digital outputs. ; You can check that all digital pinsare set at the same voltage as ; the power source using a voltmeter or Module LTIL-A (the LED ; should light up) ; Note: RE3 is an input-only pin ; http://curuxa.org ;=================================================================== LIST P=16F722, R=hex, W=1 INCLUDE p16f722.inc ORG 0x00 GOTO Main ORG 0x04 GOTO Interrupts Main ORG 0x05 MOVLW 0 BANKSEL TRISA MOVWF TRISA MOVWF TRISB MOVWF TRISC loop MOVLW 0xFF BANKSEL PORTA MOVWF PORTA MOVWF PORTB MOVWF PORTC GOTO loop ;=================================================================== ;========================== INTERRUPTS ============================= Interrupts GOTO Interrupts ;do nothing ;====================== END OF INTERRUPTS ========================== END
Category: Main Boards
|
|