Add 25LC512 support, make eep_spi.py more self-explanatory.

README.md

@@ -67,6 +67,7 @@ In the table below the Interface column includes page size in bytes.
 | Various      | Various   | SPI 4096  | <=32MiB |   Flash    | [FLASH.md](./flash/FLASH.md)  |
 | STM          | M95M02-DR | SPI 256   | 256KiB  |   EEPROM   | [SPI.md](./eeprom/spi/SPI.md) |
 | Microchip    | 25xx1024  | SPI 256   | 128KiB  |   EEPROM   | [SPI.md](./eeprom/spi/SPI.md) |
+| Microchip    | 25xx512*  | SPI 256   |  64KiB  |   EEPROM   | [SPI.md](./eeprom/spi/SPI.md) |
 | Microchip    | 24xx512   | I2C 128   |  64KiB  |   EEPROM   | [I2C.md](./eeprom/i2c/I2C.md) |
 | Microchip    | 24xx256   | I2C 128   |  32KiB  |   EEPROM   | [I2C.md](./eeprom/i2c/I2C.md) |
 | Microchip    | 24xx128   | I2C 128   |  16KiB  |   EEPROM   | [I2C.md](./eeprom/i2c/I2C.md) |
@@ -76,6 +77,7 @@ In the table below the Interface column includes page size in bytes.
 | Adafruit     | 1895      | I2C n/a   |  32KiB  |   FRAM     | [FRAM.md](./fram/FRAM.md)     |
 | Adafruit     | 4677      | SPI n/a   |   8MiB  |   SPIRAM   | [SPIRAM.md](./spiram/SPIRAM.md) |
 
+Parts marked * have been tested by users (see below).  
 The SPIRAM chip is equivalent to Espressif ESP-PSRAM64H.
 
 The flash driver now has the capability to support a variety of chips. The
@@ -88,6 +90,7 @@ following have been tested to date:
 | Cypress S25FL064L |  8         |
 | Winbond W25Q32JV  |  4         |
 
+
 It is likely that other chips with 4096 byte blocks will work but I am unlikely
 to be able to support hardware I don't possess. Users should check datasheets
 for compatibility.
@@ -106,6 +109,9 @@ Winbond W25Q128JV Flash 128MiB tested by
 [mweber-bg](https://github.com/peterhinch/micropython_eeprom/issues/8#issuecomment-917603913).  
 This requires setting `cmd5=False`.
 
+Microchip 25LC512 SPI EEPROM 64KiB tested by
+[ph1lj-6321](https://github.com/peterhinch/micropython_eeprom/issues/10).
+
 ## 1.5 Performance
 
 FRAM and SPIRAM are truly byte-addressable: speed is limited only by the speed

eeprom/spi/eep_spi.py

@@ -1,7 +1,7 @@
 # eep_spi.py MicroPython test program for Microchip SPI EEPROM devices.
 
 # Released under the MIT License (MIT). See LICENSE.
-# Copyright (c) 2019 Peter Hinch
+# Copyright (c) 2019-2022 Peter Hinch
 
 import uos
 import time
@@ -149,3 +149,11 @@ def full_test(stm=False):
             print('Page {} readback failed.'.format(page))
             break
         page += 1
+
+test_str = """Available tests (see SPI.md):
+test(stm=False)  Basic hardware test.
+full_test(stm=False)  Thorough hardware test.
+fstest(format=False, stm=False)  Filesystem test (see doc).
+cptest(stm=False)  Copy files to filesystem (see doc).
+"""
+print(test_str)

eeprom/spi/eeprom_spi.py

@@ -1,8 +1,8 @@
-# eeprom_spi.py MicroPython driver for Microchip 128KiB SPI EEPROM device,
-# also STM 256KiB chip.
+# eeprom_spi.py MicroPython driver for EEPROM chips (see README.md for
+# tested devices).
 
 # Released under the MIT License (MIT). See LICENSE.
-# Copyright (c) 2019 Peter Hinch
+# Copyright (c) 2019-2022 Peter Hinch
 
 import time
 from micropython import const
@@ -29,7 +29,7 @@ class EEPROM(BlockDevice):
 
     def __init__(self, spi, cspins, size=128, verbose=True, block_size=9):
         # args: virtual block size in bits, no. of chips, bytes in each chip
-        if size not in (128, 256):
+        if size not in (64, 128, 256):
             print('Warning: possible unsupported chip. Size:', size)
         super().__init__(block_size, len(cspins), size * 1024)
         self._stm = size == 256