Universal Serial Bus Microcontroller Series
1. General Description
The EM78M611 is a series of Universal Serial Bus 8-bit RISC Multi-Time Programming
(MTP) microcontrollers. It is specifically designed for USB low speed device application and
to support legacy device such as PS/2 keyboard. The EM78M611 also support one device
address and three endpoints. With no firmware involved, these series of microcontrollers can
automatically identify and decode Standard USB Command to EndPoint Zero.
The EM78M611 is implemented on a RISC architecture. It has eight-level stack and eight
interrupt sources. Each device has 144 bytes of general purpose SRAM and 6K bytes of
program ROM, and is embedded with 4 bytes of E2PROM. The EM78M611 has up to 11
pins with the capacity of sinking large current.
These series of chips have many powerful features, including :
Dual Clock mode which allows the device to run on very low power saving frequency
Pattern Detect Application function which is used in a serial transmission to count
Width Modulation that can generate a duty-cycle-programmable signal
24-channel AD converter with up to 10 bits resolution.
Operating voltage 4.4V ~ 5.25V
Low-cost solution for low-speed USB devices, such as keyboard, joystick, and
USB Specification Compliance
Universal Serial Bus Specification Version 1.1
USB Device Class Definition for Human Interface Device (HID), Firmware
Specification Version 1.1
Support 1 device address and 3 endpoints
P75(D-) has an internal pull-high resistor (1.5K Ohm)
USB protocol handling
USB device state handling
Identifying and decoding of Standard USB commands to EndPoint Zero
This spec. may change without further notice.
06/ 18/ 2003(V1.0)