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-------------------------------------------------------------------------------
STMicroelectronics M93C66 Microwire EEPROM
-------------------------------------------------------------------------------
This is a set of example captures of the Microwire traffic from a
STMicroelectronics M93C66 Microwire EEPROM.
Details:
http://www.st.com/resource/en/datasheet/m93c86-r.pdf
Logic analyzer setup
--------------------
The logic analyzer used was an MCU123 Saleae Logic clone (at 4MHz):
Probe M93C66 pin
----------------------
1 S / CS
3 C / SK
4 D / SI
5 Q / SO
M93C66 pin 6 (ORG) was tied high to use the x16 memory organisation (i.e.,
16-bit words).
PulseView was used to capture the trace with the following parameters:
- sample rate: 4 MHz
- samples: 50 k
- trigger: rising channel 1 (CS)
- pre-trigger: 5%
st_m93c66.sr
------------
The M93C66 EEPROM has the same following marking:
C66WP
(ST) K431
The communication is initiated by a custom software implementation for a
STM32F103C8 using the Microwire protocol as master.
The master performs the following actions:
- Read 16-bits word 0x4242 at 8-bit address 0x0
- Read first words (4x 0x4242) starting at address 0x0
- Enable write and erase
- Erase word at address 0x0 and wait until ready
- Erase complete EEPROM and wait until ready
- Write word 0x4242 at address 0x0 and wait until ready
- Write word 0x4242 on complete EEPROM and wait until ready
- Disable write and erase
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