PSoC® Creator™ Component Datasheet Cyclic Redundancy Check (CRC) 2.40 Features 1 to 64 bits Time Division Multiplexing mode Requires clock and data for serial bit stream input Serial data in, parallel result Standard [CRC-1 (parity bit), CRC-4 (ITU-T G.704), CRC-5-USB, etc.] or custom polynomial Standard or custom seed value Enable input provides synchronized operation with other components General Description The default use of the Cyclic Redundancy Check (CRC) component is to compute the CRC from a serial bit stream of any length. The input data is sampled on the rising edge of the data clock. The CRC value is reset to 0 before starting or can optionally be seeded with an initial value. On completion of the bitstream, the computed CRC value may be read out. When to Use a CRC You can use the default CRC component as a checksum to detect alteration of data during transmission or storage. CRCs are popular because they are simple to implement in binary hardware, are easy to analyze mathematically, and are particularly good at detecting common errors caused by noise in transmission channels. Cypress Semiconductor Corporation • 198 Champion Court • San Jose, CA 95134-1709 • 408-943-2600 Document Number: 001-86301 Rev. ** Revised February 20, 2013 Cyclic Redundancy Check (CRC) PSoC® Creator™ Component Datasheet Input/Output Connections This section describes the various input and output connections for the CRC. An asterisk (*) in the list of I/Os indicates that the I/O may be hidden on the symbol under the conditions listed in the description of that I/O. clock – Input The CRC requires a data input that provides the serial bitstream used to calculate the CRC. A data clock input is also required in order to correctly sample the serial data input. The input data is sampled on the rising edge of the data clock. reset – Input The reset input defines the signal to synchronous reset the CRC. enable – Input The CRC component runs after it is started and as long as the Enable input is held high. This input provides synchronized operation with other components. di – Input Data input that provides the serial bitstream used to calculate the CRC. Page 2 of 20 Document Number: 001-86301 Rev. ** PSoC® Creator™ Component Datasheet Cyclic Redundancy Check (CRC) Component Parameters Drag a CRC component onto your design and double click it to open the Configure dialog. This dialog has several tabs to guide you through the process of setting up the CRC component. Polynomial Tab Standard Polynomial This parameter allows you to choose one of the standard CRC polynomials provided in the Standard polynomial combo box or generate a custom polynomial. The additional information about each standard polynomial is given in the tool tip. The default is CRC-16. Polynomial Name Polynomial Use Custom User defined General CRC-1 x+1 Parity 4 CRC-4-ITU x +x+1 CRC-5-ITU x + x + x +1 CRC-5-USB x +x +1 CRC-6-ITU x +x+1 CRC-7 x +x +1 CRC-8-ATM x +x +x+1 CRC-8-CCITT CRC-8-Maxim 5 4 5 2 ITU G.704 2 ITU G.704 USB 6 ITU G.704 7 3 8 2 8 7 3 8 5 4 Telecom systems, MMC ATM HEC 2 x +x +x +x +1 x +x +x +1 Document Number: 001-86301 Rev. ** 1-Wire bus 1-Wire bus Page 3 of 20 Cyclic Redundancy Check (CRC) PSoC® Creator™ Component Datasheet Polynomial Name CRC-8 CRC-8-SAE Polynomial 8 7 6 4 8 4 3 2 Use 2 x +x +x +x +x +1 General x +x +x +x +1 9 5 SAE J1850 CRC-10 x 10 4 CRC-12 x 12 +x 11 +x +x +x+1 CRC-15-CAN x 15 +x 14 +x CRC-16-CCITT x 16 +x 12 +x +1 CRC-16 x 16 +x 15 +x +1 24 23 18 32 26 23 32 28 27 26 25 32 30 29 28 26 +x +x +x +x+1 3 10 General 2 8 7 Telecom systems 4 3 +x +x +x +x +1 CAN 5 XMODEM,X.25, V.41, Bluetooth, PPP, IrDA, CRCCCITT 2 USB +x 17 +x 22 +x 14 +x 16 +x 11 +x 12 +x 10 7 6 5 4 +x +x +x +x +x 3 General CRC-24-Radix64 x +x +x +x+1 CRC-32-IEEE802.3 x +x +x 2 +x +x+1 +x 11 +x 10 +x +x +x +x CRC-32C x +x +x +x +x +x +x 13 11 10 9 8 6 x +x +x +x +x +x +1 23 22 +x 20 +x 19 +x 18 +x 14 + General CRC-32K x +x +x +x +x +x +x 10 7 6 4 2 x +x +x +x +x +x+1 20 19 +x 17 +x 16 +x 15 +x 11 + General CRC-64-ISO x CRC-64-ECMA x +x +x +x +x +x +x +x +x +x +x + 39 38 37 35 33 32 31 29 27 24 23 x +x +x +x +x +x +x +x +x +x +x + 22 21 19 17 13 12 10 9 7 4 x + x + x + x + x + x + x + x + x + x + x +1 64 64 4 8 7 5 4 3 +x +x +x+1 62 57 55 Ethernet, MPEG2 ISO 3309 54 53 52 47 46 45 40 ECMA-182 Polynomial Value This parameter is represented in hexadecimal format. It is calculated automatically when one of the standard polynomials is selected. You may also enter it manually (see Custom Polynomials). Seed Value This parameter is represented in hexadecimal format. The maximum possible value is 2 N – 1. N This parameter defines the degree of polynomial. Possible values are 1 to 64 bits. The table with numbers indicates which degrees are included in the polynomial. Cells with selected numbers are blue; others are white. The number of active cells is equal to N. Numbers are arranged in reverse order. You may click on the cell to select or deselect a number. Polynomial representation This parameter displays the resulting polynomial in mathematical notation. Page 4 of 20 Document Number: 001-86301 Rev. ** PSoC® Creator™ Component Datasheet Cyclic Redundancy Check (CRC) Custom Polynomials You may enter a custom polynomial in three different ways: Small Changes to Standard Polynomial Choose one of the standard polynomials. Select the necessary degrees in the table by clicking on the appropriate cells; the text in Standard polynomial changes to Custom. The polynomial value is recalculated automatically based on the polynomial that is represented. Use Polynomial Degrees Enter a custom polynomial in the N textbox; the text in Standard polynomial changes to Custom. Select the necessary degrees in the table by clicking on the appropriate cells. Check the view of the polynomial in Polynomial representation. The polynomial value is recalculated automatically based on the polynomial that is represented. Use Hexadecimal Format Enter a polynomial value in hexadecimal form in the Polynomial Value text box. Press [Enter] or switch to another control; the text in Standard polynomial changes to Custom. The N value and degrees of polynomial will be recalculated based on the entered polynomial value. Document Number: 001-86301 Rev. ** Page 5 of 20 Cyclic Redundancy Check (CRC) PSoC® Creator™ Component Datasheet Advanced Tab Implementation This parameter defines the implementation of the CRC component: Time Division Multiplex or Single Cycle. The default is Single Cycle. Local Parameters (For API use) These parameters are used in the API and are not exposed in the GUI: PolyValueLower (uint32) – Contains the lower half of the polynomial value in hexadecimal format. The default is 0xB8h (LFSR= [8,6,5,4]) because the default resolution is 8. PolyValueUpper (uint32) – Contains the upper half of the polynomial value in hexadecimal format. The default is 0x00h because the default resolution is 8. SeedValueLower (uint32) – Contains the lower half of the seed value in hexadecimal format. The default is 0xFFh because the default resolution is 8. SeedValueUpper (uint32) – Contains the upper half of the seed value in hexadecimal format. The default is 0 because the default resolution is 8. Page 6 of 20 Document Number: 001-86301 Rev. ** PSoC® Creator™ Component Datasheet Cyclic Redundancy Check (CRC) Clock Selection There is no internal clock in this component. You must attach a clock source. Note Generation of the proper CRC sequence for a resolution of greater than eight requires a clock signal four times greater than the data rate, if you select Time Division Multiplex for the Implementation parameter. Application Programming Interface Application Programming Interface (API) routines allow you to configure the component using software. The following table lists and describes the interface to each function. The subsequent sections cover each function in more detail. By default, PSoC Creator assigns the instance name “CRC_1” to the first instance of a component in a given design. You can rename it to any unique value that follows the syntactic rules for identifiers. The instance name becomes the prefix of every global function name, variable, and constant symbol. For readability, the instance name used in the following table is “CRC.” Function Description CRC_Start() Initializes seed and polynomial registers with initial values. Computation of CRC starts on rising edge of input clock. CRC_Stop() Stops CRC computation. CRC_Wakeup() Restores the CRC configuration and starts CRC computation on rising edge of input clock. CRC_Sleep() Stops CRC computation and saves the CRC configuration. CRC_Init() Initializes the seed and polynomial registers with initial values. CRC_Enable() Starts CRC computation on rising edge of input clock. CRC_SaveConfig() Saves the seed and polynomial registers. CRC_RestoreConfig() Restores the seed and polynomial registers. CRC_WriteSeed() Writes the seed value. CRC_WriteSeedUpper() Writes the upper half of the seed value. Only generated for 33- to 64-bit CRC. CRC_WriteSeedLower() Writes the lower half of the seed value. Only generated for 33- to 64-bit CRC. CRC_ReadCRC() Reads the CRC value. CRC_ReadCRCUpper() Reads the upper half of the CRC value. Only generated for 33- to 64-bit CRC. CRC_ReadCRCLower() Reads the lower half of the CRC value. Only generated for 33- to 64-bit CRC. CRC_WritePolynomial() Writes the CRC polynomial value. RC_WritePolynomialUpper() Writes the upper half of the CRC polynomial value. Only generated for 33- to 64bit CRC. Document Number: 001-86301 Rev. ** Page 7 of 20 Cyclic Redundancy Check (CRC) PSoC® Creator™ Component Datasheet Function Description CRC_WritePolynomialLower() Writes the lower half of the CRC polynomial value. Only generated for 33- to 64bit CRC. CRC_ReadPolynomial() Reads the CRC polynomial value. CRC_ReadPolynomialUpper() Reads the upper half of the CRC polynomial value. Only generated for 33- to 64bit CRC. CRC_ReadPolynomialLower() Reads the lower half of the CRC polynomial value. Only generated for 33- to 64bit CRC. Global Variables Variable CRC_initVar Description Indicates whether the CRC has been initialized. The variable is initialized to 0 and set to 1 the first time CRC_Start() is called. This allows the component to restart without reinitialization after the first call to the CRC_Start() routine. If reinitialization of the component is required, then the CRC_Init() function can be called before the CRC_Start() or CRC_Enable() function. void CRC_Start(void) Description: Initializes seed and polynomial registers with initial values. Computation of CRC starts on rising edge of input clock. Parameters: None Return Value: None Side Effects: None void CRC_Stop(void) Description: Stops CRC computation. Parameters: None Return Value: None Side Effects: None Page 8 of 20 Document Number: 001-86301 Rev. ** PSoC® Creator™ Component Datasheet Cyclic Redundancy Check (CRC) void CRC_Sleep(void) Description: Stops CRC computation and saves the CRC configuration. Parameters: None Return Value: None Side Effects: None void CRC_Wakeup(void) Description: Restores the CRC configuration and starts CRC computation on the rising edge of the input clock. Parameters: None Return Value: None Side Effects: None void CRC_Init(void) Description: Initializes the seed and polynomial registers with initial values. Parameters: None Return Value: None Side Effects: None void CRC_Enable(void) Description: Starts CRC computation on the rising edge of the input clock. Parameters: None Return Value: None Side Effects: None void CRC_SaveConfig(void) Description: Saves the initial seed and polynomial registers. Parameters: None Return Value: None Side Effects: None Document Number: 001-86301 Rev. ** Page 9 of 20 Cyclic Redundancy Check (CRC) PSoC® Creator™ Component Datasheet void CRC_RestoreConfig(void) Description: Restores the initial seed and polynomial registers. Parameters: None Return Value: None Side Effects: None void CRC_WriteSeed(uint8/16/32 seed) Description: Writes the seed value. Parameters: uint8/16/32 seed: Seed value Return Value: None Side Effects: The seed value is cut according to mask = 2 Resolution – 1. For example, if CRC Resolution is 14 bits, the mask value is: 14 mask = 2 – 1 = 0x3FFFu. The seed value = 0xFFFFu is cut: seed and mask = 0xFFFFu and 0x3FFFu = 0x3FFFu. void CRC_WriteSeedUpper(uint32 seed) Description: Writes the upper half of the seed value. Only generated for 33- to 64-bit CRC. Parameters: uint32 seed: Upper half of the seed value Return Value: None Side Effects: The upper half of the seed value is cut according to mask = 2 Resolution – 32 – 1. For example, if CRC Resolution is 35 bits, the mask value is: (35 – 32) 2 3 – 1 = 2 – 1 = 0x0000 0007u. The upper half of the seed value = 0x0000 00FFu is cut: upper half of seed and mask = 0x0000 00FFu and 0x0000 0007u = 0x0000 0007u. void CRC_WriteSeedLower(uint32 seed) Description: Writes the lower half of the seed value. Only generated for 33- to 64-bit CRC. Parameters: uint32 seed: Lower half of the seed value Return Value: None Side Effects: None Page 10 of 20 Document Number: 001-86301 Rev. ** PSoC® Creator™ Component Datasheet Cyclic Redundancy Check (CRC) uint8/16/32 CRC_ReadCRC(void) Description: Reads the CRC value. Parameters: None Return Value: uint8/16/32: Returns the CRC value Side Effects: None uint32 CRC_ReadCRCUpper(void) Description: Reads the upper half of the CRC value. Only generated for 33- to 64-bit CRC. Parameters: None Return Value: uint32: Returns the upper half of the CRC value Side Effects: None uint32 CRC_ReadCRCLower(void) Description: Reads the lower half of the CRC value. Only generated for 33- to 64-bit CRC. Parameters: None Return Value: uint32: Returns the lower half of the CRC value Side Effects: None void CRC_WritePolynomial(uint8/16/32 polynomial) Description: Writes the CRC polynomial value. Parameters: uint8/16/32 polynomial: CRC polynomial Return Value: None Side Effects: – 1. For example, if CRC The polynomial value is cut according to mask = 2 14 Resolution is 14 bits, the mask value is: mask = 2 – 1 = 0x3FFFu. Resolution The polynomial value = 0xFFFFu is cut: polynomial and mask = 0xFFFFu and 0x3FFFu = 0x3FFFu. Document Number: 001-86301 Rev. ** Page 11 of 20 Cyclic Redundancy Check (CRC) PSoC® Creator™ Component Datasheet void RC_WritePolynomialUpper(uint32 polynomial) Description: Writes the upper half of the CRC polynomial value. Only generated for 33- to 64-bit CRC. Parameters: uint32 polynomial: Upper half of the CRC polynomial value Return Value: None Side Effects: The upper half of the polynomial value is cut according to mask = 2 example, if CRC Resolution is 35 bits, the mask value is: (35 – 32) 2 (Resolution – 32) – 1. For 3 – 1 = 2 – 1 = 0x0000 0007u. The upper half of the polynomial value = 0x0000 00FFu is cut: upper half of polynomial and mask = 0x0000 00FFu and 0x0000 0007u = 0x0000 0007u. void CRC_WritePolynomialLower(uint32 polynomial) Description: Writes the lower half of the CRC polynomial value. Only generated for 33- to 64-bit CRC. Parameters: uint32 polynomial: Lower half of the CRC polynomial value Return Value: None Side Effects: None uint8/16/32 CRC_ReadPolynomial(void) Description: Reads the CRC polynomial value. Parameters: None Return Value: uint8/16/32: Returns the CRC polynomial value Side Effects: None uint32 CRC_ReadPolynomialUpper(void) Description: Reads the upper half of the CRC polynomial value. Only generated for 33- to 64-bit CRC. Parameters: None Return Value: uint32: Returns the upper half of the CRC polynomial value Side Effects: None Page 12 of 20 Document Number: 001-86301 Rev. ** PSoC® Creator™ Component Datasheet Cyclic Redundancy Check (CRC) uint32 CRC_ReadPolynomialLower(void) Description: Reads the lower half of the CRC polynomial value. Only generated for 33- to 64-bit CRC. Parameters: None Return Value: uint32: Returns the lower half of the CRC polynomial value. Side Effects: None MISRA Compliance This section describes the MISRA-C:2004 compliance and deviations for the component. There are two types of deviations defined: project deviations – deviations that are applicable for all PSoC Creator components specific deviations – deviations that are applicable only for this component This section provides information on component-specific deviations. Project deviations are described in the MISRA Compliance section of the System Reference Guide along with information on the MISRA compliance verification environment. The CRC component has the following specific deviations: MISRAC:2004 Rule Rule Class (Required/ Advisory) Rule Description Description of Deviation(s) 14.3 R Before preprocessing, a null statement shall only occur on a line by itself; it may be followed by a comment provided that the first character following the null statement is a white-space character. Deviation is caused by using a macro that has a group of statements contained within curly braces. The macro is CRC_EXECUTE_DFF_RESET. A MISRA compliant implementation would require the use of this macro to be followed by a semicolon. This could introduce failures in designs that used this macro directly. 19.4 R C macros shall only expand to a braced initializer, a constant, a parenthesized expression, a type qualifier, a storage class specifier, or a do-while-zero construct. Deviation is caused by using a macro that has a group of statements contained within curly braces. The macro is CRC_EXECUTE_DFF_RESET. A MISRA compliant implementation would require the use of this macro to be followed by a semicolon. This could introduce failures in designs that used this macro directly. 19.7 A A function should be used in preference to a function-like macro. Deviation is caused by the macro CRC_IS_CRC_ENABLE. If removed this would introduce failures in designs that used this macro directly. Document Number: 001-86301 Rev. ** Page 13 of 20 Cyclic Redundancy Check (CRC) PSoC® Creator™ Component Datasheet Sample Firmware Source Code PSoC Creator provides many example projects that include schematics and example code in the Find Example Project dialog. For component-specific examples, open the dialog from the Component Catalog or an instance of the component in a schematic. For general examples, open the dialog from the Start Page or File menu. As needed, use the Filter Options in the dialog to narrow the list of projects available to select. Refer to the “Find Example Project” topic in the PSoC Creator Help for more information. Functional Description The CRC is implemented as a linear feedback shift register (LFSR). The shift register computes the LFSR function, the polynomial register holds the polynomial that defines the LFSR polynomial, and the seed register enables initialization of the starting data. The seed and polynomial registers must be initialized before starting the component. Computation of an N-bit LFSR result is specified by a polynomial with N + 1 terms, the last of which is the X0 term where X0 = 1. For example, the widely used CRC-CCITT 16-bit polynomial is X16 + X12 + X5 + 1. The CRC algorithm assumes the presence of the X0 term, so that the polynomial for an N-bit result can be expressed by an N bit rather than (N + 1)-bit specification. To specify the polynomial specification, write an (N + 1)-bit binary number corresponding to the full polynomial, with 1s for each term present. The CRC-CCITT polynomial would be 10001000000100001b. Then, drop the right-most bit (the X 0 term) to obtain the CRC polynomial value. To implement the CRC-CCITT example, the polynomial register is loaded with a value of 8810h. A rising edge of the input clock shifts each bit of the input data stream, MSB first, through the shift register, computing the specified CRC algorithm. Eight clocks are required to compute the CRC for each byte of input data. Note that the initial seed value is lost. This is usually of no consequence because the seed value is only used to initialize the Shift register once, for each data set. Block Diagram and Configuration Page 14 of 20 Document Number: 001-86301 Rev. ** PSoC® Creator™ Component Datasheet Cyclic Redundancy Check (CRC) Timing Diagrams clock Figure 1. Time Division Multiplex Implementation Mode reset time enable time di time time CRC Calculated Values clock Figure 2. Single Cycle Implementation Mode reset time enable time di time time CRC Calculated Values Document Number: 001-86301 Rev. ** Page 15 of 20 Cyclic Redundancy Check (CRC) PSoC® Creator™ Component Datasheet Resources The CRC component is placed throughout the UDB array. The component utilizes the following resources. Resource Type Configuration Datapath Cells Macrocel ls Status Cells Control Cells DMA Channels Interrupts 8-Bits Single Cycle 1 3 – 1 – – 16-Bits Single Cycle 2 3 – 1 – – 24-Bits Single Cycle 3 3 – 1 – – 32-Bits Single Cycle 4 3 – 1 – – 16-Bits Time Division 1 9 – 1 – – 24-Bits Time Division 2 10 – 1 – – 32-Bits Time Division 2 9 – 1 – – 40-Bits Time Division 3 10 – 1 – – 48-Bits Time Division 3 9 – 1 – – 56-Bits Time Division 4 10 – 1 – – 64-Bits Time Division 4 9 – 1 – – API Memory Usage The component memory usage varies significantly, depending on the compiler, device, number of APIs used and component configuration. The following table provides the memory usage for all APIs available in the given component configuration. The measurements have been done with the associated compiler configured in Release mode with optimization set for Size. For a specific design the map file generated by the compiler can be analyzed to determine the memory usage. PSoC 3 (Keil_PK51) Configuration PSoC 4 (GCC) PSoC 5LP (GCC) Flash SRAM Flash SRAM Flash SRAM Bytes Bytes Bytes Bytes Bytes Bytes 8-Bits Single Cycle 155 2 242 8 246 8 16-Bits Single Cycle 202 2 260 8 260 8 24-Bits Single Cycle 294 2 320 8 294 8 32-Bits Single Cycle 212 2 280 8 282 8 Page 16 of 20 Document Number: 001-86301 Rev. ** PSoC® Creator™ Component Datasheet Cyclic Redundancy Check (CRC) PSoC 3 (Keil_PK51) Configuration PSoC 4 (GCC) PSoC 5LP (GCC) Flash SRAM Flash SRAM Flash SRAM Bytes Bytes Bytes Bytes Bytes Bytes 16-Bits Time Division 234 2 320 8 320 8 24-Bits Time Division 548 2 404 8 398 8 32-Bits Time Division 567 2 432 8 434 8 40-Bits Time Division 687 2 568 8 580 8 48-Bits Time Division 839 2 610 8 638 8 56-Bits Time Division 938 2 662 8 702 8 64-Bits Time Division 1045 2 710 8 718 8 DC and AC Electrical Characteristics Specifications are valid for –40 °C £ TA £ 85 °C and TJ £ 100 °C, except where noted. Specifications are valid for 1.71 V to 5.5 V, except where noted. DC Characteristics Parameter IDD Description Min Typ [1] Max Units Component current consumption 8-Bits Single Cycle – 10 – µA/MHz 16-Bits Single Cycle – 16 – µA/MHz 24-Bits Single Cycle – 26 – µA/MHz 32-Bits Single Cycle – 33 – µA/MHz 16-Bits Time Division – 17 – µA/MHz 24-Bits Time Division – 29 – µA/MHz 32-Bits Time Division – 29 – µA/MHz 40-Bits Time Division – 35 – µA/MHz 48-Bits Time Division – 35 – µA/MHz 56-Bits Time Division – 43 – µA/MHz 64-Bits Time Division – 44 – µA/MHz 1. Device IO and clock distribution current not included. The values are at 25 °C. Document Number: 001-86301 Rev. ** Page 17 of 20 Cyclic Redundancy Check (CRC) PSoC® Creator™ Component Datasheet AC Characteristics Parameter fCLOCK Description Max [2] Min Typ Units 8-Bits Single Cycle – – 41 MHz 16-Bits Single Cycle – – 32 MHz 24-Bits Single Cycle – – 30 MHz 32-Bits Single Cycle – – 28 MHz 16-Bits Time Division – – 34 MHz 24-Bits Time Division – – 24 MHz 32-Bits Time Division – – 29 MHz 40-Bits Time Division – – 24 MHz 48-Bits Time Division – – 27 MHz 56-Bits Time Division – – 23 MHz 64-Bits Time Division – – 28 MHz Component clock frequency 2. The values provide a maximum safe operating frequency of the component. The component may run at higher clock frequencies, at which point you will need to validate the timing requirements with STA results. Component Changes This section lists the major changes in the component from the previous version. Version 2.40 Description of Changes Reason for Changes / Impact Updated datasheet with memory usage for PSoC 4. Updated Defines for [25 – 32] bit Single Cycle Implementation Mode for PSoC 4. 2.30 Added MISRA Compliance section. The component has specific deviations described. Added PSoC 4A support Changed Timing Diagrams 2.20 Added PSoC 5LP support 2.10 Changed error messages and their appearance for implementation parameter. Fixed setting polynomial degree 'N' to 64-bit resolution. Page 18 of 20 Document Number: 001-86301 Rev. ** PSoC® Creator™ Component Datasheet Version Description of Changes Cyclic Redundancy Check (CRC) Reason for Changes / Impact Fixed polynomial value validation. 2.0.b Minor datasheet edits and updates 2.0.a Added characterization data to datasheet Minor datasheet edits and updates 2.0 Added support for PSoC 3 ES3 silicon. Changes include: 4x clock for Time Division Multiplex Implementation added Single Cycle Implementation on 1x clock now available for 1 to 32 bits. Time Division Multiplex Implementation on 4x clock now available for 9 to 64 bits. Asynchronous input signal reset is added. Synchronous input signal enable is added. Added new 'Advanced' page to the Configure dialog for the Implementation (Time Division Multiplex, Single Cycle) parameter New requirements to support the PSoC 3 ES3 device, thus a new 2.0 version of the CRC component was created. Added CRC_Sleep()/CRC_Wakeup() and CRC_Init()/CRC_Enable() APIs. To support low-power modes, as well as to provide common interfaces to separate control of initialization and enabling of most components. Updated functions CRC_WriteSeed() and CRC_WriteSeedUpper(). The mask parameter was used to cut the seed value to define CRC resolution while writing. Add validator to Resolution parameter. The resolution of CRC is 1 to 64 bits. The validator was added to restrict input values. Add reset DFF triggers to polynomial write functions: CRC_WritePolynomial(), CRC_WritePolynomialUpper() and CRC_WritePolynomialLower(). The DFF triggers need to be set in proper state (most significant bit of polynomial, always 1) before CRC calculation starts. To meet this condition, any write to the Seed or Polynomial registers resets the DFF triggers. Updated Configure dialog to allow the Expression View for the following parameters: 'PolyValueLower', 'PolyValueUpper', 'SeedValueLower', 'SeedValueLower' Expression View is used to directly access the symbol parameters. This view allows you to connect component parameters with external parameters, if desired. Updated Configure dialog to add error icons for various parameters. If you enter an incorrect value in a text box, the error icon displays with a tool tip of the problem description. This provides easier use than a separate error message. Document Number: 001-86301 Rev. ** Page 19 of 20 Cyclic Redundancy Check (CRC) Version 1.20 Description of Changes PSoC® Creator™ Component Datasheet Reason for Changes / Impact Changed method of API generation. In version 1.10, This change allows users to view and make APIs were generated by settings from the changes to the generated API files, and they will customizer. For 1.20, APIs are provided by the .c not be overwritten on subsequent builds. and .h files like most other components. Seed and Polynomial parameters were changed to have hexadecimal representation. Change was made to comply with corporate standard. © Cypress Semiconductor Corporation, 2009-2013. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use of any circuitry other than circuitry embodied in a Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor intended to be used for medical, life support, life saving, critical control or safety applications, unless pursuant to an express written agreement with Cypress. Furthermore, Cypress does not authorize its products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges. PSoC® is a registered trademark, and PSoC® Creator™ and Programmable System-on-Chip™ are trademarks of Cypress Semiconductor Corp. All other trademarks or registered trademarks referenced herein are property of the respective corporations. Any Source Code (software and/or firmware) is owned by Cypress Semiconductor Corporation (Cypress) and is protected by and subject to worldwide patent protection (United States and foreign), United States copyright laws and international treaty provisions. Cypress hereby grants to licensee a personal, non-exclusive, non-transferable license to copy, use, modify, create derivative works of, and compile the Cypress Source Code and derivative works for the sole purpose of creating custom software and or firmware in support of licensee product to be used only in conjunction with a Cypress integrated circuit as specified in the applicable agreement. Any reproduction, modification, translation, compilation, or representation of this Source Code except as specified above is prohibited without the express written permission of Cypress. Disclaimer: CYPRESS MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A HALFICULAR PURPOSE. Cypress reserves the right to make changes without further notice to the materials described herein. Cypress does not assume any liability arising out of the application or use of any product or circuit described herein. Cypress does not authorize its products for use as critical components in lifesupport systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress’ product in a life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges. Use may be limited by and subject to the applicable Cypress software license agreement. Page 20 of 20 Document Number: 001-86301 Rev. **