AN1525 STMicroelectronics, AN1525 Datasheet
AN1525
Related parts for AN1525
AN1525 Summary of contents
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... I tify the chip enable inputs that allow the same bus to interface with other memories. 2 Figure BUS PROTOCOL April 2002 APPLICATION NOTE 2 C EEPROM with an ST52x520 microcontroller using 2 C bus protocol. The three successive bits iden- AN1525 Author: C.Ruggieri 1/12 ...
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... AN1525 - APPLICATION NOTE 3 HARDWARE DESCRIPTION The electrical schematic of the circuit, which the proposed program refers to is shown in Figure 2. The Pa0/SCL pin of the microcontroller is connected to the SCL line and the PA1/SDA pin is connected with the SDA line for bus synchronization. The pushbutton is connected with pin PA7 (external interrupt, INT) in order to select the reading and writing phase ...
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... ST24C04. The software is developed with Visual FIVE and allows sequential writing of a maximum of 8 bytes (for ST24C04 certain memory address and the reading, afterwards, of the same amount of bytes. The software that is proposed can be found in file I2CGP.FS4 (see file AN1525.FS4 in the applica- tion note page at the following web site: http://www.st.com/five ). ...
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... AN1525 - APPLICATION NOTE In the example that has been proposed, bit b1 (that represents bit A8 of the memory address) wasn’t used in the Device Select Code. The user can select only one range of addresses, which range from 0 to 255. In order to address memory locations that exceed the quantity indicated, the program has to be modified. ...
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... ST52x520 datasheet for the complete diagram of the sequences, relative to the I crocontroller). Figure 8. 7 BIT MASTER TRANSFER SEQUENCING AN1525 - APPLICATION NOTE 2 C peripheral and afterwards enables the pe interrupt routine. ...
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... AN1525 - APPLICATION NOTE Figure 9. EXTERNAL INTERRUPT WINDOW 2 4 Interrupt Window The routine of the interrupt window of the I that are necessary for the correct reading and writing sequence. As can be seen in Figure 8, each time a START condition begins or data begins, the I quest that will have to be managed by the user (EVx events). ...
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... FLAG register, control will pass to the conditional block BTF10, which determines if the operation to be performed is that of reading or writing (operation which is established by the value of bit 0 of the FLAG register, modified with every exterted pressure on the pushbutton). AN1525 - APPLICATION NOTE 2 C peripheral will not continue operations requested if ...
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... AN1525 - APPLICATION NOTE 4.2.2 Writing Block. If writing performed, the program will execute the instructions of the block shown in Figure 12 (bit 0 of the FLAG register = 0). The conditional Buffer block verifies when the number of bytes sent from the peripheral of the ST52x520 microcontroller to the memory has achieved the number of bytes indicated by the user in the BYTE_N variable ...
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... Once the BTF10 block condition is performed, seeing that bit0 of register FLAG is set to ‘1’, the program will perform the reading block represented by Figure 14. Figure 14. READ FLOW BLOCKS C routine. After each START, bit 0 of the SR1 register is set to ‘1’ and the AN1525 - APPLICATION NOTE 9/12 ...
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... AN1525 - APPLICATION NOTE The first conditional block (R_ _or_W) verifies if bit 3 of the FLAG register has already been set to ‘1’. In case it is negative, the routine sets this bit to ‘1’ and sends the START condition, exiting immediately after 2 the I C routine via the Retl1 control. ...
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... The PC3 signal chang- es state before sending or receiving every byte of data from the memory. Lastly, the PC4 signal changes state everytime the STOP condition is sent. REFERENCES [1] ST52x520 - Datasheet, STMicroelectronics, 2001 [2] ST24C0Z1 - Datasheet, STMicroelectronics, 1999 [3] Visual FIVE 5.0 - User Manual, STMicroelectronics, 2002 AN1525 - APPLICATION NOTE 11/12 ...
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... AN1525 - APPLICATION NOTE Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are subject to change without notice ...