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| ttcps Xilinx SDK Drivers API Documentation

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ttcps Documentation

This is the driver for one 16-bit timer counter in the Triple Timer Counter (TTC) module in the Ps block.The TTC module provides three independent timer/counter modules that can each be clocked using either the system clock (pclk) or an externally driven clock (ext_clk). In addition, each counter can independently prescale its selected clock input (divided by 2 to 65536). Counters can be set to decrement or increment.

Each of the counters can be programmed to generate interrupt pulses: . At a regular, predefined period, that is on a timed interval . When the counter registers overflow . When the count matches any one of the three 'match' registers

Therefore, up to six different events can trigger a timer interrupt: three match interrupts, an overflow interrupt, an interval interrupt and an event timer interrupt. Note that the overflow interrupt and the interval interrupt are mutually exclusive.

Initialization & Configuration

An XTtcPs_Config structure is used to configure a driver instance. Information in the XTtcPs_Config structure is the hardware properties about the device.

A driver instance is initialized through XTtcPs_CfgInitialize(InstancePtr, CfgPtr, EffectiveAddr). Where CfgPtr is a pointer to the XTtcPs_Config structure, it can be looked up statically through XTtcPs_LookupConfig(DeviceID), or passed in by the caller. The EffectiveAddr can be the static base address of the device or virtual mapped address if address translation is supported.

Interrupts

Interrupt handler is not provided by the driver, as handling of interrupt is application specific.

stack usage(in bytes)

        XTtcPs_LookupConfig : 32
        XTtcPs_CfgInitialize : 80
        XTtcPs_SetMatchValue : 32
        XTtcPs_GetMatchValue : 48
        XTtcPs_SetPrescaler : 48
        XTtcPs_GetPrescaler : 48
        XTtcPs_CalcIntervalFromFreq : 48
        XTtcPs_SetOptions : 48
        XTtcPs_GetOptions : 48
        XTtcPs_SelfTest : 48
        XTtcPs_InterruptHandler : 48
        XTtcPs_SetStatusHandler : 48

Memory foot-print(in bytes)

        XTtcPs_LookupConfig : 72
        XTtcPs_CfgInitialize : 304
        XTtcPs_SetMatchValue : 168
        XTtcPs_GetMatchValue : 176
        XTtcPs_SetPrescaler : 172
        XTtcPs_GetPrescaler : 152
        XTtcPs_CalcIntervalFromFreq : 228
        XTtcPs_SetOptions : 424
        XTtcPs_GetOptions : 200
        XTtcPs_SelfTest : 148
        XTtcPs_InterruptHandler : 88
        XTtcPs_SetStatusHandler : 140

Execution Time(in usec)

        XTtcPs_LookupConfig : 8.31
        TtcPs_CfgInitialize : 1.30
        XTtcPs_SetMatchValue : 1.10
        XTtcPs_GetMatchValue : 1.00
        XTtcPs_SetPrescaler : 1.09
        XTtcPs_GetPrescaler : 1.00
        XTtcPs_CalcIntervalFromFreq : 1.29
        XTtcPs_SetOptions: 1.91
        XTtcPs_GetOptions: 2.55
        XTtcPs_SelfTest: .85

Assumptions of Use

        1.The default setting for a timer/counter is:
         - Overflow Mode
         - Internal clock (pclk) selected
         - Counter disabled
         - All Interrupts disabled
         - Output waveforms disabled

Compiler Name

      gcc

Compiler version

      8.2.0

Compiler options

        -DARMR5 -Wall -O0 -g3 -c -fmessage-length=0 -MT"$@" -mcpu=cortex-r5 -mfloat-abi=hard  -mfpu=vfpv3-d16 -I<include_path>
        -Wall -O0 -g3 -c -fmessage-length=0 -MT"$@" -mcpu=cortex-a72 -I<include_path>
        -Wall -O0 -g3 -c -fmessage-length=0 -MT"$@" -I<include_path>

User Defined data types

        u8      1 byte
        u16     2 bytes
        u32     4 bytes / 1 word
        u64     8 bytes / double word

    MODIFICATION HISTORY:

    Ver   Who    Date     Changes

    1.00a drg/jz 01/20/10 First release..
    2.0   adk    12/10/13 Updated as per the New Tcl API's
    3.0     pkp    12/09/14 Added support for Zynq Ultrascale Mp.Also code
                    modified for MISRA-C:2012 compliance.
    3.2   mus    10/28/16 Modified XTtcPs_GetCounterValue and XTtcPs_SetInterval
                          macros to return 32 bit values for zynq ultrascale+mpsoc
          ms   01/23/17 Modified xil_printf statement in main function for all
                        examples to ensure that "Successfully ran" and "Failed"
                        strings are available in all examples. This is a fix
                        for CR-965028.
          ms   03/17/17 Added readme.txt file in examples folder for doxygen
                        generation.
    3.4   ms   04/18/17 Modified tcl file to add suffix U for all macros
                        definitions of ttcps in xparameters.h
    3.5   srm  10/06/17 Added new typedef XMatchRegValue for match register width
    3.8   aru  12/19/18 Modified in XTtcPs_ClearInterruptStatus function to clear
                        Interrupt status register by reading instead of writing it.