EM78612
Universal Serial Bus Microcontroller
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•Product Specification(V1.0)03.2 2.2006
(This specification is subject to changewithout further notice)
1 General Description
The EM78612 is a series of Universal Seria l Bus 8-bit RISC microcontrollers. It is
specifically designed for USB low speed de vice application and to support legacy
device such as PS/2 mouse. The EM78612 also support one devic e address and two
endpoints..
The EM78612 is implemented on a RISC architecture. It has five-level stack and six
interrupt sources. The amount of General Input/Output pins is up to12. Each device
has 80 bytes SRAM. The ROM size of the EM78612 is 2K.
These series o f chips have Dual Clock mode which allows the device to run on low
power saving frequency.
2 Features
Low-cost solution for low-speed USB devices, such as mouse, joystick, and
gamepad.
USB Specification Compliance
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Universal Serial Bus Specification Version 1.1
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USB Device Class Definition for Human Interface Device (HID), Firmware
Specification Version 1.1
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Support 1 device address and 2 endpoints (EP0 and EP1)
USB Application
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USB protocol handling
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USB device state handling
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Identifies and decodes Standard USB commands to EndPoint Zero
PS/2 Application Support
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Built-in PS/2 port interface
Built-in 8-bit RISC MCU
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5 level stacks for subroutine and interrupt
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6 available interrupts
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8-bit real time clock/counter (TCC) with overflow inter rupt
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Built-in RC oscillator free running for WatchDog Timer and Dual clock mode
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Two independent programmable prescalers for WDT and TCC
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Two methods of power saving:
1. Power-down mode (SLEEP mode)
2. Low frequency mode.
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Two clocks per instruction cycle
I/O Ports