projects / sigrok-dumps.git / blame
| Commit | Line | Data |
|---|---|---|
| 5e3b071c KR |
1 | ------------------------------------------------------------------------------- |
| 2 | STMicroelectronics M93C66 Microwire EEPROM | |
| 3 | ------------------------------------------------------------------------------- | |
| 4 | ||
| 5 | This is a set of example captures of the Microwire traffic from a | |
| 6 | STMicroelectronics M93C66 Microwire EEPROM. | |
| 7 | ||
| 8 | Details: | |
| 9 | http://www.st.com/resource/en/datasheet/m93c86-r.pdf | |
| 10 | ||
| 11 | ||
| 12 | Logic analyzer setup | |
| 13 | -------------------- | |
| 14 | ||
| 15 | The logic analyzer used was an MCU123 Saleae Logic clone (at 4MHz): | |
| 16 | ||
| 17 | Probe M93C66 pin | |
| 18 | ---------------------- | |
| 19 | 1 S / CS | |
| 20 | 3 C / SK | |
| 21 | 4 D / SI | |
| 22 | 5 Q / SO | |
| 23 | ||
| 24 | M93C66 pin 6 (ORG) was tied high to use the x16 memory organisation (i.e., | |
| 25 | 16-bit words). | |
| 26 | ||
| 27 | PulseView was used to capture the trace with the following parameters: | |
| 28 | ||
| 29 | - sample rate: 4 MHz | |
| 30 | - samples: 50 k | |
| 31 | - trigger: rising channel 1 (CS) | |
| 32 | - pre-trigger: 5% | |
| 33 | ||
| 34 | ||
| 35 | st_m93c66.sr | |
| 36 | ------------ | |
| 37 | ||
| 38 | The M93C66 EEPROM has the same following marking: | |
| 39 | ||
| 40 | C66WP | |
| 41 | (ST) K431 | |
| 42 | ||
| 43 | The communication is initiated by a custom software implementation for a | |
| 44 | STM32F103C8 using the Microwire protocol as master. | |
| 45 | ||
| 46 | The master performs the following actions: | |
| 47 | ||
| 48 | - Read 16-bits word 0x4242 at 8-bit address 0x0 | |
| 49 | - Read first words (4x 0x4242) starting at address 0x0 | |
| 50 | - Enable write and erase | |
| 51 | - Erase word at address 0x0 and wait until ready | |
| 52 | - Erase complete EEPROM and wait until ready | |
| 53 | - Write word 0x4242 at address 0x0 and wait until ready | |
| 54 | - Write word 0x4242 on complete EEPROM and wait until ready | |
| 55 | - Disable write and erase |