Introduction to the 16-bit PIC24F Microcontroller Family

Editor's Notes

• #3: Welcome to the training module on Microchip PIC24 Family Introduction. This module will take a closer look at the capabilities of PIC24F microcontrollers.
• #4: The PIC24F is meant to be a cost effective first step into our 16-bit products. Microchip offers four 16-bit families that share common core architectures, instruction set, development tools, peripherals and pin-outs. A designer using a Microchip 16-bit product can balance their controller selection based on cost, performance, peripherals and even DSP capability. All four families use the same tool set allowing a smooth transition without the need to learn or purchase new tools.
• #5: This continues from the previous slide which shows pictorially number of products present in PIC24F, PIC24H, dsPIC30F, dsPIC33F 16 bit families. The lower band indicates a continuation from the 8-bit microcontroller line into the realm of 16-bit controllers. At the beginning of the band, with 16 MIPS, is PIC24F, the entry level 16-bit product. The PIC24F provides a performance jump from the PIC18 microcontrollers with minimal cost impact. Next on the microcontroller band is the PIC24H – the highest performance 16-bit microcontroller with about 40 MIPS of performance. The upper band adds our Digital Signal Controller, or DSC product line with up to 40 MIPS performance and DSP instructions.
• #6: Microchip’s 16-bit product line is designed to rival many 32-bit controllers in performance, with the ease of use typically associated with the 8-bit product lines. The common architecture makes it easy to optimize a design for cost and to reduce risk by providing speed, memory and peripheral upgrade paths. All devices in Microchip’s 16-bit product line use the same MPLAB® Integrated Development Environment (IDE) and MPLAB ICD 2 development tool chain shared by Microchip’s 8-bit products.
• #7: Using internal benchmarks based on industry standards and internal application code Microchip’s entry level PIC24F family executes at 16 MHz with about 14 MIPS throughput showing the advantage of the RISC architecture’s single cycle instruction execution. The graph shows the results of compiling C code with various C Compilers for a number of processors. The code complied was a combination of approximately 40K of application code used in various application notes. The higher the number the larger the resulting program memory. A smaller number indicates better c code efficiency.
• #8: All of the devices in the PIC24F family are built with the same base peripheral set. The primary difference being the Flash memory sizes, which include 64 KB, 96 KB and 128KB The devices start with the 16 MIPS PIC24F core. Around the core is a peripheral set that includes the 16 channels of 10-bit A/D converter and two analog comparators. The device includes a watchdog timer and five channels of 16-bit timers, four of which can be cascaded to form two 32-bit timers. The PIC24F family also includes a real time clock with calendar function that is often used for time stamping data logged information or communications data. The devices also include two I2C’s, two UARTS and two SPI channels. To compliment the various serial channels there is also a Cyclic Redundancy Check peripheral that can be used to ensure data is or will be correctly communicated.
• #9: PIC24F is a Harvard Architecture which has separate program and Data Memory. Speed of the processor is 16MIPS. When operating off a 32 MHz clock, the PIC24F can expect the performance to be roughly ½ of the clock rate, or equivalent to instruction execution time. In addition to faster execution time and a 16-bit data bus there are several other additions to the core. The interrupt structure of the PIC24F family is significantly upgraded. The PIC24F provides an independent interrupt vector for each interrupt source.
• #10: The PICI24F family provides 16 working register. The PIC24F implements 16-bit math, including a 17 X 17 single cycle multiply. The architecture also implements a single cycle multiple bit shifter, or barrel shifter. The instruction set and addressing modes work to improve the PIC24F C code efficiency. Finally, the PIC24F core incorporates a “repeat” instruction. This instruction allows a math instruction, or a memory transfer instruction to be repeated a specified number of times
• #11: the PIC24F provides a natural migration path up from the PIC18. First, the PIC24F provides increased memory. On the first family we expand the RAM to 8 KB and the Flash to 128 KB. It would be a fair guess that the 128 KB Flash on the first family will not be the limit for too long. Along with the increased memory is of course increased performance, with a 16-bit MCU operating at 16 MIPS. The device contains five 16-bit timers, four of which can be cascaded to form two 32-bit timers. There is also a new high speed 10-bit ADC. The 10-bit ADC is capable of conversion rates of up to 500K samples per second. JTAG Boundary Scan has been added to the PIC24F family to assist in board level testing and in system programming.
• #12: The PIC24F CPU incorporates hardware support for both multiplication and division. This includes a dedicated hardware multiplier and support hardware for 16-bit divisor. The PIC24F ALU is 16 bits wide and is capable of addition, subtraction, bit shifts and logic operations. Depending on the operation, the ALU may affect the values of the Carry (C), Zero (Z), Negative (N), Overflow (OV) and Digit Carry (DC) Status bits in the SR register
• #13: This slide shows regarding the Programmers Model of Working register. It has 16 working registers each of 16-bit wide which are exclusively used during multiplication and division. Its program counter is 23-bit wide.
• #14: PIC24F is a Harvard architecture device which consist of separate program and data Memory space and Busses. This architecture allows the direct access of program memory from the data space during code execution. Program address space spans 4M instructions it is addressable by 24-bit value derived from 23-bit PC or from table operation or data space remapping. User access to program memory space is restricted to lower half of address range(000000h-7FFFFFh)
• #15: The part number begins with PIC24FJ which is a 16-bit entry level PIC Microcontroller. The Flash memory size immediately follows the FJ in the part number. The G indicates that the device is general purpose. In the future other designations will be added to match the feature set. The A0 are used to identify specific derivatives. The last two digits are a rough indication of the number of pins divided by 10.
• #16: Microchip’s PIC microcontrollers are supported by the MPLAB Integrated Development Environment (IDE), which is used to integrate the development, debug and software utilities available when developing code for a product. MPLAB is the only platform you will need to develop for a Microchip microcontroller and can cover products from 6 pins to 100 pins and code space from 512 Bytes to 256 KB. Language tools are available from Microchip in the form of an Assembler (MPASM™), a linker (MPLINK™) and a C Complier (MPLAB C30). Development tool support also includes software simulators, emulators, development boards and programmers. Available utilities such as Flash programming, project management and MPLIB™ Librarian are also included in the MPLAB IDE. Beyond the Microchip tool-chain are a number of third party tool vendors that also provide valuable tool capabilities such as compilers, production programmers and software tools, including RTOS, libraries and device drivers
• #17: MPLAB IDE is designed to work with all of Microchip’s In Circuit Emulators and programmers. The Microchip 16-bit families are supported by the MPLAB ICD 2, MPLAB REAL ICE, and the MPLAB PM3 programmer. All of the tools are designed to work with MPLAB. MPLAB ICD 2 is a Flash upgradeable in-circuit debugger designed to operate with any PIC® microcontroller. The MPLAB ICD 2 can be connected to and powered by the USB connection on the host PC. It can also connect through a RS-232 port. As an in circuit debugger it will enable a device to single step, or set up to 3 break points and then upload relevant data to the host PC. While the MPLAB ICD 2 can program a device we also support the MPLAB PM3 for lab or low volume production programming
• #18: The Explorer 16 board is designed to interface with the MPLAB ICD 2 to provide a complete development platform. The board includes a PIC24FJ128GA010 and a dsPIC33 DSC. The processors can be changed by changing the Processor Interconnect Module, or PIM. The board includes the power supplies, buttons, switches and displays that you would expect in a development board. It also includes a small prototyping area and socket connector for use with Microchip’s PICtail™ Plus daughter boards. At this time two daughter cards are available to quickly enable the Explorer 16 board to connect with a SD/MMC card or to connect to Ethernet through a ENC28J60.
• #19: Thank you for taking the time to view this presentation on Microchip PIC24F microcontrollers. If you would like to learn more or go on to purchase some of these devices, you may either click on the part list link, or simply call our sales hotline. For more technical information you may either visit the Microchip site – link shown – or if you would prefer to speak to someone live, please call our hotline number, or even use our ‘live chat’ online facility.