DAE6502.002 8 November 2011 MAS6502 DATA SHEET EXTENSION • Writing data to the EEPROM TE3 VDD OSC EEPROM VREFP PI P SDA T NI P COMMON R3 VDD ADC 2 CONTROL IC SCL T XCLR R1 VREFN EOC R4 P T R2 T MAS6502 GND TEST TE1 TE2 INTRODUCTION The MAS6502 16 bit Analog-to-Digital Converter (ADC) has a 256 bit (32 bytes) EEPROM memory. 8 bits (1 byte) have been reserved for storing internal clock oscillator trimming data leaving 248 bits (31 bytes) free for use. This document gives instructions for writing data to the EEPROM memory. 1 (3) DAE6502.002 8 November 2011 EEPROM WRITE PROCEDURE START POWER UP DEVICE Connect supply voltage VDD INITIAL CONDITIONS Optional: Reset device by XCLR or by writing any data on the reset register 30HEX ENABLE EEPROM WRITE Write 55HEX to the EEPROM write enable register 3BHEX WRITE DATA TO EEPROM (free memory area 41HEX…5FHEX) Write data byte (8-bit) to selected EEPROM memory address WAIT Wait minimum 16ms after writing byte (8-bit) to EEPROM VERIFY WRITTEN DATA Read the written data byte (8-bit ) from the EEPROM memory address yes Write more data? no DISABLE EEPROM WRITE Write 00HEX to the EEPROM write enable register 3BHEX STOP Figure 1. Flow chart for MAS6502 EEPROM write 2 (3) DAE6502.002 8 November 2011 EEPROM WRITE PROCEDURE See figure 1 on previous page showing the EEPROM write procedure. Next the data can be written to the EEPROM memory one byte (8-bit) at a time. It is necessary to have a delay of minimum 16ms after programming each byte (8-bit). The success of each write can be verified by reading back the data (8-bit) and comparing it to the original byte (8-bit). Make sure in the beginning of the EEPROM write procedure that the MAS6502 initial conditions are met. Connecting VDD triggers power-on-reset (POR) but to make sure the device is reset an additional reset can be given using the XCLR pin or 2 writing any data on the reset register 30HEX via I C serial bus. After all data bytes are written the EEPROM memory can be protected from write and erasing by writing 00HEX to the EEPROM write enable register 3BHEX. EEPROM write is enabled by writing value 55HEX to EEPROM write enable register 3BHEX. Any other value in this register disables the EEPROM write. The default register value after power on is 00HEX. Table 1 below shows the MAS6502 register and EEPROM data addresses. See also the MAS6502 datasheet for further details of registers, EEPROM and serial bus communication. REGISTER AND EEPROM DATA ADDRESSES Table 1. Register and EEPROM data addresses A7 A6 A5 A4 A3 A2 A1 A0 HEX (X=0) X 0 0 0 0 0 0 0 00 X X 0 1 0 0 A4 0 A3 0 A2 0 A1 0 A0 0 01…1F 40 X 1 0 A4 A3 A2 A1 A0 41…5F X X 1 1 0 0 0 0 30 X X X X X X X X X X X X X X X X X X 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 0 0 0 0 1 1 1 1 1 0 0 1 1 0 0 1 1 1 0 1 0 1 0 1 0 1 37 38 39 3A 3B 3C 3D 3E 3F Description EEPROM; erase internal clock oscillator trimming, reserved! EEPROM; erase data at address [A4:A0] EEPROM; read or write internal clock oscillator trimming, reserved! EEPROM; read or write data at address [A4:A0] Reset register; contains no data, write any data for reset Test and trim control register Oscillator frequency control register Data input register for EEPROM Control register for EEPROM Write and erase enable for EEPROM Status register for EEPROM MSB conversion result LSB conversion result ADC control register Note E E E E R R R R R R R R R R X = Don’t care, E = EEPROM, R= Register MICRO ANALOG SYSTEMS OY CONTACTS Micro Analog Systems Oy Kutomotie 16 FI-00380 Helsinki, FINLAND Tel. +358 10 835 1100 Fax +358 10 835 1109 http://www.mas-oy.com NOTICE Micro Analog Systems Oy reserves the right to make changes to the products contained in this data sheet in order to improve the design or performance and to supply the best possible products. Micro Analog Systems Oy assumes no responsibility for the use of any circuits shown in this data sheet, conveys no license under any patent or other rights unless otherwise specified in this data sheet, and makes no claim that the circuits are free from patent infringement. Applications for any devices shown in this data sheet are for illustration only and Micro Analog Systems Oy makes no claim or warranty that such applications will be suitable for the use specified without further testing or modification. 3 (3)