LPC Microcontrollers Knowledge Base

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Because the LPC55S69 has PowerQuad, in SDK example code, the FFT/FIR/IIR and the other DSP function are implemented by the Powerquad module instead of the Cortex-CM33 core. This is the Powerquad example to implement the DSP function:' But if customers want to use CMSIS-DSP to implement the DSP function based on Cortex-CM33 instead of Powerquad module, customers can not import SDK example, he has to create a new project, this is the procedures: 1)Create a new project by clicking New->Create a new C/C++ Project 2)select the processor like LPC55S69 3)In the following menu,click CMSIS Driver, and check the CMSIS_DSP_Library and CMSIS_DSP_Library_Source You have to click the Driver which can select your peripherals driver you will use. 3)as the following screenshot, after completion, you can see the CMSIS-DSP source code and library have included in the project

LPC4088 Closed Payment Loop Demo - Running the demo Directly after programming the FLASH has finished, or after power-up, the demo is ready to use. The following screen will be presented: In order to use the demo, first the Mifare Classic card must be initialized. This can be done by holding the card in-range of the RFID antenna and pushing the center button of the Embedded Artists base-board. If successful, a confirmation message is shown for half a second. Next, credit must be added to the card. This is done by again holding the card in-range of the RFID antenna, but now pushing the joystick to the top-position (towards the edge of the board). Every time the joystick is pushed to the top-position, $10 will be added to the card. If successful, a confirmation message is shown for half a second after pressing the joystick. The credit can be queried by pressing the "Query Card" button. Now that the card is initialized and charged, products can be purchased. By pushing the product-buttons in the 3x3 grid, products can be selected. Every time a product is selected, it is added to the listbox and the total cost is updated. Upon pressing "Checkout", the credit available on the card is read-in, the total cost is subtracted and the new credit is written back to the card. A confirmation of this action will be shown.

The minimum saturation current spec of Inductor is 300mA in the LPC55xx internal DC/DC converter, why is it 300mA, what is the actual current flowing through the inductor? 1)This is internal DC/DC converter block diagram for LPC55xx, on the LX pin, the 4.7uH inductor and 22uF capacitor are required, the FB pin is the detected pin to sense the output voltage, the DC/DC converter provide about 1.1V power for the VDD_PMU power supply pin. Let's discuss the current flowing through the inductor L1 via LX pin 2)compute the actual current flowing the inductor The above circuit is the illustrating block diagram, the control regulation uses PWM signal to control the MOSFET, but the high time of the PWM signal is constant for each PWM cycle, in other words, the on-time of the MOSFET is constant, for the LPC55S69 internal DC/DC converter, the on-time Δt is 0.52us, which means that the interval of MOSFET turning-on time is 0.52us. Assume that the VDC_IN is 3.3V, the output voltage of the DC/DC converter is 1.1V, the constant high time of the PWM signal is 0.52uS. when the MOSFET is on, the capacitor will be charged. The above figure is the waveform tested on the LX pin of LPC55S68 on the LPC55S69-EVK board, you can measure via scope that the high time of the yellow PWM signal is 0.52uS, during which the MOSFET turns on, the capacitor is charged. The inductor works in DCM mode(discontinuous current mode) The incremental current flowing the inductor during the MOSFET turns on: ΔI= (VDC_IN-VDC_OUT)* Δt/L=(3.3V-1.1V)*0.52*10**(-6)/4.7*10**(-6)=243mA. 3)The actual flowing current through the inductor is about 250mA for each PWM cycle, so when you select the inductor, the saturation current spec must be greater than actual current, the minimum required saturation current spec for the 4.7uH inductor is 300mA, when you select inductor for the DC/DC converter, you should select the inductor with 300mA or above saturation current .

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New update to errata will be published regarding the vendor_usage field in the PFR. In ROM, the 16-bit monotonic counter is implemented in the upper 16 bits of the 32-bit VENDOR_USAGE field and the inverse of the monotonic counter is in the lower 16 bits. Users must take care when using the ROM API to increment the upper end of this field and write the inverse on the lower 16 bits in order for ROM to validate the value correctly. The initial value that shall be written is 0x0000FFFF. Then the updates will be as follows: 0x0001FFFE 0x0002FFFD . . 0x0005FFFA . . 0x1010EFEF . . 0xFFFF0000 Example Code using ROM API: *This example demonstrates the increment of the version in CFPA page as well as the vendor usage, it does not cover all use cases, so please use this as a reference only* case APP_INCREASE_VENDOR_USAGE_ONLY: PRINTF("Disable Flash Protect...\r\n"); /* Initialize flash driver */ FLASH_Init(&flashInstance); if (FFR_Init(&flashInstance) == kStatus_Success) { PRINTF("Flash init successfull!!. Halting...\r\n"); } else { error_trap(); } status = FFR_GetCustomerInfieldData(&flashInstance, (uint8_t *)g_CFPAData, 0x0, FLASH_FFR_MAX_PAGE_SIZE); PRINTF("\r\n"); PRINTF("Header 0x%08x , Version 0x%08x , SecureFW Version 0x%08x , NonSecureFW Version 0x%08x\r\n", g_CFPAData[0], g_CFPAData[1], g_CFPAData[2], g_CFPAData[3]); PRINTF("ImageKey Revoke 0x%08x , Reserved 0x%08x , RothRevoke 0x%08x , Vendor Usage 0x%08x\r\n", g_CFPAData[4], g_CFPAData[5], g_CFPAData[6], g_CFPAData[7]); PRINTF("NS PIN 0x%08x , NS DFLT 0x%08x , Enable FA Mode 0x%08x , Reserved1 0x%08x\r\n", g_CFPAData[8], g_CFPAData[9], g_CFPAData[10], g_CFPAData[11]); PRINTF("\r\n"); /* Clean-up CFPA area */ g_CFPAData[8] = 0; g_CFPAData[9] = 0; /*Increase Monotonic counter*/ p32 = (uint32_t *)(uint32_t)g_CFPAData; version = p32[1]; if (version == 0xFFFFFFFFu) { return kStatus_Fail; } version++; p32[1] = version; PRINTF("Version to write: 0x%08x \r\n", version); /*Increase Vendor Usage*/ uint32_t vendor_usage = p32[7]; if(vendor_usage == 0x0) { vendorUsage_right = 0xFFFF; vendorUsage_left = 0x0000; } else { vendorUsage_right = vendor_usage & 0xFFFF; vendorUsage_left = vendor_usage >> 16; } vendorUsage_left += 0x1; vendorUsage_right -= 0x1; vendor_usage = (vendorUsage_left << 16) | vendorUsage_right; p32[7] = vendor_usage; PRINTF("Vendor_Usage to write: 0x%08x \r\n", vendor_usage); Status = FFR_InfieldPageWrite(&flashInstance, (uint8_t *)g_CFPAData, FLASH_FFR_MAX_PAGE_SIZE); if (kStatus_FLASH_Success == Status) { status = kStatus_Success; PRINTF("CFPA Write Done!\r\n"); } else { status = kStatus_Fail; }

LPC Microcontrollers Knowledge Base

LPC Microcontrollers Knowledge Base

Discussions

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