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+# Brother Pattern Programming Devices
+
+Various electronic experiments with pattern programming on Brother knitting machines.
+
+## brothercart
+
+Reverse engineering of the Stitch Pattern Cartridge II.
+
+This card is equipped with 32KB RAM and 32KB ROM.
+The ROM is an EPROM without erase window and probably contains some built-in
+knitting patterns. The RAM can be programmed freely.
+
+To ensure data retention on the RAM chip, there is a huge 3V lithium battery
+soldered onto the PCB. There is also some discrete logic to support memory
+bank switching (probably).
+
+## emulator
+
+A re-implementation of the memory cartridge with a microcontroller, an SPI
+flash chip (optional, 64KB..512KB), and a microSD card slot.
+
+The cartridge memory bus is directly attached to the microcontroller.
+
+Memory access will not be as fast as the original RAM and ROM, so make sure
+not to run the bus faster than the microcontroller can feed data.