Page 104 - PDA Robotics Using Your Personal Digital Assistant to Control Your Robot

PDA 05 5/30/03 11:35 AM Page 80
PDA Robotics
The following information about the specifics of this chip from the
data sheets explains the details of its inner workings. I highly recom-
mend going to www.microchip.com to download any updates. There
is enough information provided in the sheets to write a C or C++ com-
piler for the chip if you are so inclined. When the sheet explains how
the chip does the analog to digital conversions, you could use that
information to create one of your own externally with a capacitor. This
would allow you to buy a chip that has only digital input/output pins
and create the A/D converter yourself. The following summarizes
what you need to know. Features include:

• High-performance RISC CPU
• Only 35 single-word instructions to learn

• All single-cycle instructions except for program branches, which
are two cycle

• Operating speed: DC—20 MHz clock input DC—200 ns instruc-
tion cycle

• Up to 8K 14 words of FLASH program memory, up to 368 8
bytes of data memory (RAM), up to 256 x 8 bytes of EEPROM
data memory

• Pinout compatible to the PIC16C73B/74B/76/77
• Interrupt capability (up to 14 sources)
• Eight-level-deep hardware stack

• Direct, indirect, and relative addressing modes

• Power-on Reset (POR)
• Power-up Timer (PWRT) and Oscillator Start-up Timer (OST)
• Watchdog Timer (WDT) with its own on-chip RC oscillator for
reliable operation
• Programmable code protection

• Power saving SLEEP mode

• Selectable oscillator options
• Low-power, high-speed CMOS FLASH/EEPROM technology
• Fully static design

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