EM78M612
Universal Serial Bus Microcontroller Series
EM78M612
Universal Serial Bus Microcontroller
V1.1
Specification Revision History
Version
1.0
Content
Update
• Initial Version
2003/03/05
• Correction for some text in General Description－P2,rom size 12K→2K
• Correction for Pin Configuration of EM78M612XBP－P5
• ADC Converter Channel Selector Table fixed－P16,CH1 Reserved
1.1
• Added PDA Register Description－P20,IOC9
2004/04/28
• Correction for EEPROM Function Description－P24
• Changes made to PDA Function Description－P29-32
• Revised ADC Converter ready bit for ADC Operation－P17,P34,RAS[7]
This specification may change without further notice.
2004/4/28 V1.1
1
EM78M612
Universal Serial Bus Microcontroller Series
SPECIFICATION
1 General Description
The EM78M612 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 mouse. The EM78M612 also support one device
address and two endpoints. With no firmware involved, these series of microcontrollers can
automatically identify and decode Standard USB Command to EndPoint Zero.
The EM78M612 is implemented on a RISC architecture. It has five-level stack and eight
interrupt sources. The amount of General Input/Output pins is up to 15. Each device has 112
bytes SRAM and is embedded with 4 bytes of E2PROM. The ROM size of the EM78M612 is
2K.
These series of chips have special features that accommodate your needs. These features
are:
Dual Clock mode which allows the device to run on very low power saving frequency
Pattern Detecting Application function which is used in a serial transmission to count
waveform width
Width Modulation that can generate a duty-cycle-programmable signal
AD converter with up to 10 bits resolution.
2 Features
Low-cost solution for low-speed USB devices, such as mouse, joystick, and gamepad.
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 2 endpoints
USB Application
USB protocol handling
USB device state handling
Identifies and decodes Standard USB commands to EndPoint Zero
PS/2 Application Support
Auto-detects PS/2 or USB port
Built-in PS/2 port interface
This specification may change without further notice.
2004/4/28 V1.1
2
EM78M612
Universal Serial Bus Microcontroller Series
Built-in 8-bit RISC MCU
5 level stacks for subroutine and interrupt
8 available interrupts
8-bit real time clock/counter (TCC) with overflow interrupt
Built-in RC oscillator free running for WatchDog Timer and Dual clock mode
Two independent programmable prescalers for WDT and TCC
Two methods of power saving:
1. Power-down mode (SLEEP mode)
2. Low frequency mode.
Two clocks per instruction cycle
Multi-time programmable
I/O Ports
Up to 15 general purposes I/O pins grouped into two ports (Port 6 and 7).
Up to 2 LED sink pins
Each GPIO pin of Ports 6 has an internal programmable pull-high resistor (200K
Ohms)
Each GPIO pin wakes up the MCU from sleep mode by input state change
Internal Memory
Built-in 2048K*13 bits Program ROM
Built-in 112 bytes general purpose registers (SRAM)
Built-in USB Application FIFOs.
Built-in 4 bytes E2PROM (EM78M612＊B, EM78M612＊D)
Operation Frequency
Normal Mode: MCU runs on the external oscillator frequency
Dual Clock Mode: MCU runs at the frequency of 256KHz (or 32KHz, 4KHz, 500Hz),
emitted by the internal oscillator with the external ceramic resonator (or crystal)
turned off to save power.
Built-in Pattern Detecting Application for serial signal transmission
Built-in Pulse Width Modulation (PWM)
Up to 2 channels PWM function on P.64 (PWM1) and P.65 (PWM2).
Up to 8-bit resolution PWM output
Up to 8 selections of duty cycles
Built-in 15-Channel Analog-to-Digital Converter (ADC)
Built-in AD Converter with 10-bit resolution
This specification may change without further notice.
2004/4/28 V1.1
3
EM78M612
Universal Serial Bus Microcontroller Series
4 ADC conversion rates: 256K/128K/64K/32K
Built-in 3.3V Voltage Regulator
For MCU power supply
Pull-up source for the external USB resistor on D-pin.
Package Type
16 pin PDIP/SOP (EM78M612(A/B/C/D) A P/M)
18 pin PDIP/SOP (EM78M612(A/B/C/D) B P/M)
20 pin PDIP/SOP (EM78M612(A/B/C/D) C P/M)
20 pin SSOP (EM78M612(A/B/C/D) EM)
24 pin PDIP/SOP (EM78M612(A/B/C/D) D P/M)
24 pin SSOP (EM78M612(A/B/C/D) FM)
3 Type Definition
The EM78M612 series has sereval types of packaging. Each type is divided into 4 modules,
namely; original, with E2PROM, with A/D converter, and with both E2PROM and A/D
converter. Hence, packaging configuration for each series is defined. The Table 3.1 below
summarizes which series of the EM78M612 belong to which module.
Original
With E PROM
2
With A/D
Converter
With Both
EM78M612A＊＊
EM78M612B＊＊
EM78M612C＊＊
EM78M612D＊＊
Table 3-1 Packaging Summary of EM78M612 Series IC
This specification may change without further notice.
2004/4/28 V1.1
4
EM78M612
Universal Serial Bus Microcontroller Series
4 Applications
This microcontroller is designed for USB low speed device application or non-USB
embedded device. It is also suitable for PS/2 mouse application.
5 Pin Configuration
P60/VPP
1●
20
P64
P61
2
19
P65
P62
3
18
P66
P63
4
17
P67
P70
5
16
P71
P72
6
15
P73
VSS
7
14
D+/P50
P61
1●
16
P60/VPP
P62
2
15
P64
P63
3
14
P65
P70
4
13
P71
VSS
5
12
D+/P50
VNN
6
11
D-/P51
VNN
8
13
D-/P51
V3.3V
7
10
VDD
V3.3V
9
12
VDD
OSCI
8
9
OSCO
OSCI
10
11
OSCO
◆EM78M612XAP
◆EM78M612XCP
P60/VPP
1●
24
P64
P61
2
23
P65
P62
3
22
P66
1●
18
P64
P63
4
21
P67
P61
2
17
P65
P70
5
20
P71
P62
3
16
P66
P72
6
19
P73
P63
4
15
P67
P74
7
18
P75
P70
5
14
P71
P76
8
17
P77
VSS
6
13
D+/P50
VSS
9
16
D+/P50
VNN
7
12
D-/P51
VNN
10
15
D-/P51
V3.3V
8
11
VDD
V3.3V
11
14
VDD
OSCI
9
10
OSCO
OSCI
12
13
OSCO
P60/VPP
◆EM78M612XBP
This specification may change without further notice.
◆EM78M612XDP
2004/4/28 V1.1
5
EM78M612
Universal Serial Bus Microcontroller Series
6 Pin Description
Symbol
I/O
OSCI
I
OSCO
I/O
Function
6MHz / 12MHz ceramic resonator or crystal input.
Return path for 6-MHz / 12MHz ceramic resonator or crystal.
Used in programming the on-chip ROM. During normal operation, this pin is
connected to Ground.
VNN
O
3.3V DC voltage output from internal regulator. This pin has to be tied to a
4.7μF capacitor.
I
P60 functins as an input pin only (no output)
For serial signal transmission application, the Pin P60 is used as a serial signal
input pin. For detailed usage and function, refer to Section 8.8, Pattern
Detecting Application of this Spec.
I/O
7 GIOP pins.
The pull high resistors (200K Ohms) and pull low resistors (15K Ohm) are
selected through pin programming.
All Port6 I/O pins are used for AD function. Furthermore,P64 & P65 can also be
used for PWM function.
I/O
Port7 offers up to 8 GIOP pins. The sink current of P70 & P71 are
programmable for driving LED.
Each pin has pull high resistors (200K Ohm) that can be selected through pin
programming.
All Port7 I/O pins can be used for AD function.
I/O
USB Plus data line interface or PS/2 line interface are user-defined through
firmware setting.
When this pin is used as a PS/2 line interface, it will generate an interrupt when
its state changes.
D- / P51
I/O
USB Minus data line interface or PS/2 line interface are user-defined through
firmware setting.
When this pin is used as a PS/2 line interface, it will generate an interrupt when
its state changes.
VDD
-
Connects to the USB power source or to a nominal 5V-power supply. Actual VDD
range can vary between 4.4V and 5.2V.
VSS
-
Connects to ground.
V3.3V
P60/VPP
P61 ~ P67
P70 ~ P77
D+ / P50
Table 7.1 Pin Descriptions
This specification may change without further notice.
2004/4/28 V1.1
6
EM78M612
Universal Serial Bus Microcontroller Series
7 Function Block Diagram
OSCI
Built-in
RC
OSCO
VDD
V3.3
3.3V
Regulator
Oscillator
Timing
Control
EEPROM
Reset &
Sleep &
Wake up
Control
Prescaler
Prescaler
WDT
TCC
WDT
Timer
R1
(TCC)
D+
D-
Stack1
Stack2
Stack3
Stack4
Stack5
R2
(PC)
Transceiver
ROM
USB
Device
Controller
Instruction
register
R3
(Status)
R AM
Interrupt
Control
R4
(RSR)
ALU
Instruction
Decoder
ACC
DATA & CONTROL BUS
PWM
ADC
I/O
Port 6
Pattern
Detect
Application
P60/PDA
P61/AD
P62/AD
P83/AD
P64/AD
P65/AD
P66/AD
P67/AD
I/O
Port 7
P70/AD
P71/AD
P72/AD
P73/AD
P74/AD
P75/AD
P76/AD
P77/AD
P50/D+
P51/D-
I/O
Port 5
Figure 7 EM78M612 Series Function Block Diagram
8 Function Description
The EM78M612 memory is organized into 4 spaces, namely; User Program Memory in
2048*13 bits ROM space, Data Memory in 112 bytes SRAM space, and USB Application
FIFOs (for EndPoint0 and EndPoint1). Furthermore, several registers are used for special
purposes.
This specification may change without further notice.
2004/4/28 V1.1
7
EM78M612
Universal Serial Bus Microcontroller Series
8.1 Program Memory
The program space of the EM78M612 is 2K bytes, and is divided into two pages. Each page
is 1K bytes long. After Reset, the 11-bit Program Counter (PC) points to location zero of the
program space.
It has two interrupt vectors, i.e., Interrupt Vectors at 0x0001 and USB Application Interrupt
Vectors at 0x000A. The Interrupt Vector applies to TCC Interrupt, High Pattern Detecting
Interrupt, Low Pattern Detecting Interrupt, and Port 5 State Changed Interrupt. The USB
Application Interrupt Vector is for USB EndPoint Zero Interrupt, USB Suspend Interrupt, USB
Reset interrupt ,and USB Host Resume Interrupt.
After an interrupt, the MCU will fetch the next instruction from the corresponding address as
illustrated in the following diagram.
After reset
PC
Address
0x0000
Reset Vector
0x0001
Interrupt Vector
0x000A
USB Application Interrupt Vector
Page 0
0x03FF
0x0400
Page 1
0x07FF
8.2
Data Memory
The Data Memory has 112 bytes SRAM space. It is also equipped with USB Application
FIFO space for USB Application. The Figure 8.1 (next page) shows the organization of the
Data Memory Space.
This specification may change without further notice.
2004/4/28 V1.1
8
EM78M612
Universal Serial Bus Microcontroller Series
8.2.1 Special Purpose Registers
When the microcontroller executes instruction, specific registers are invoked for assistance,
such as; Status Register which records the calculation status, Port I/O Control Registers
which control the I/O pins’ direction, etc. The EM78M612 series provides a lot more of other
special purpose registers with different functions.
There are 23 Special Operation Registers which are located from Address 0x00 to 0x0E in
Bank0, and from Address 0x08 to 0x0F in Bank1. On other hand, 17 more Special Control
Registers are available to control functions or I/O direction. These are arranged from
Address 0x05 to 0x0F in Bank0, and from Address 0x08 to 0x0F in Bank1.
Note that Special Control Registers can only be read or written by two instructions; IOR and
IOW. To access registers from Bank1, the Special Purpose Registers Bank selector (R3[7])
should be set first.
00
01
02
03
04
05
06
07
08
09
0A
0B
0C
0D
0E
0F
08
09
0A
0B
0C
0D
0E
0F
R0
R1
R2
R3
R4
(Indirection Addressing Register)
(Time Clock / Counter Register)
(Program Counter) & Stack
(Status Register)
(RAM Select Register)
CBK0
R5 (Data line I/O Register)
R6 (Port 6 I/O Register)
R7 (Port 7 I/O Register)
R8 (Port6 wakeup pin selection Register)
R9 (Port7 wakeup pin selection Register)
RA (High Pattern Counter Register)
RB (Low Pattern Counter Register)
RC (USB Application Status Register)
RD (USB FIFO address register)
RE (USB FIFO data register)
RF (Interrupt Status Register)
CBK1
R8S (PWM1 Duty Cycle Register)
R9S (PWM2 Duty Cycle Register)
RAS (AD Channel Select Register)
RBS (AD MSB Data Register
RCS (AD LSB Data Register)
CBK0
IOC5 (Port 5 I/O Control Register)
IOC6 (Port 6 I/O Control Register)
IOC7 (Port 7 I/O Control Register)
IOC8 (Sink Curent Control Register)
IOC9 (PDA Control Register)
IOCA (Operation mode Control Register)
IOCB (Port 6 pull low Control Register)
IOCC (Port 6 pull high Control Register)
IOCD (Port 7 pull high Control Register)
IOCE (Special Function Control Register)
IOCF (Interrupt Mask Register)
CBK1
IOC8S (PWM Control Register)
IOCAS (AD Control Register)
IOCCS (EEPROM BYTE0)
IOCDS (EEPROMBYTE1)
IOCES (EEPROMBYTE2)
IOCFS (EEPROMBYTE3)
RES (EEPROM MODE SELECT Register)
10
General Purpose Register
00
01
10
11
EP0's FIFO
EP1's FIFO
Data Byte Pointer of EP0
Data Byte Pointer of EP1
1F
B y te 0
B y te 1
B y te 2
B y te 3
B y te 4
B y te 5
B y te 6
B y te 7
20
General Purpose
Registers
(Bank0)
General Purpose
Registers
(Bank1)
General Purpose
Registers
(Bank2)
General Purpose
Registers
(Bank3)
3F
Fig 8.1 The Organization of EM78M612 Data RAM
This specification may change without further notice.
2004/4/28 V1.1
9
EM78M612
Universal Serial Bus Microcontroller Series
8.2.1.1 Operation Registers in Bank 0
The following introduces each of the Operation Registers under the Special Purpose
Registers in Bank 0. These Operation Registers are arranged according to the order of
registers’ address. Note that some registers are read only, while others are both readable
and writable.
R0 (Indirect Address Register) Default Value: (0B_0000_0000)
R0 is not a physically implemented register. Its major function is to be an indirect address
pointer. Any instruction using R0 as a pointer actually accesses the data pointed by the RAM
Select Register (R4).
R1 (Time / Clock Counter) Default Value: (0B_0000_0000)
This register TCC, is an 8-bit timer or counter. It is readable and writable as any other
register.
After Power-on reset and WatchDog reset, the initial value of this register is 0x00.
R2 (Program Counter & Stack) Default Value: (0B_0000_0000)
The EM78M612 Program Counter is an 11-bit long register that allows access to 2K bytes of
Program Memory. The Program Counter is cleared after Power-on reset or WatchDog reset.
The first instruction that is executed after a reset is located at Address 00h.
CALL
R3[5]
R2[9] ~ R2[0]
0x0000 Reset Vector
Stack 1
RET
RETL
RETI
Stack 2
Stack 3
0x0001 Interrupt Vector
Stack 4
0x000A USB Interrupt Vector
Stack 5
Page 0
0x03FF
0x0400
Page 1
0x07FF
This specification may change without further notice.
2004/4/28 V1.1
10
EM78M612
Universal Serial Bus Microcontroller Series
R3 (Status Register) Default Value:(0B_0001_1000)
7
6
5
4
3
2
1
0
SPRBS
-
PS0
T
P
Z
DC
C
R3 [0]
Carry flag.
R3 [1]
Auxiliary carry flag.
R3 [2]
Zero flag. It will be set to 1 when the result of an arithmetic or logic operation is
zero.
R3 [3]
Power down flag. It will be set to 1 during Power-on phase or by “WDTC” command
and cleared when the MCU enters into Power down mode. It remains in its previous
state after WatchDog Reset.
1: Power-on.
0: Power down
R3 [4]
Time-out flag. It will be set to 1 during Power-on phase or by “WDTC” command. It
is reset to 0 by WDT time-out.
1: WatchDog timer without overflow.
0: WatchDog timer with overflow.
The various states of Power down flag and Time-out flag at different conditions are shown
below:
T
P
1
1
0
1
1
1
1
*P
0
0
Condition
Power-on reset
WDTC instruction
WDT time-out
Power down mode
Wakeup caused by port change during Power down mode
*P: Previous status before WDT reset
R3 [5]
Page selection bit. This bit is used to select a page of program memory (refer to R2,
Program Counter).
PS0
Program Memory Page [Address]
0
Page 0 [0000-03FF]
1
Page 1 [0400-07FF]
R3 [6]
General purpose registers.
R3 [7]
Special purpose registers bank selector.
1: R8S ~ RFS; IOC8S ~ IOCFS
0: R5 ~ RF; IOC5 ~ IOCF
This specification may change without further notice.
2004/4/28 V1.1
11
EM78M612
Universal Serial Bus Microcontroller Series
R4 (RAM Select Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
BK1
BK0
Ad5
Ad4
Ad3
Ad2
Ad1
Ad0
R4 (RAM select register) contains the address of the registers.
R4 [0~5] are used to select registers in 0x00h~0x3Fh. The address 0x00~0x1F is common
space. After 0x1Fh, SRAM is grouped into four banks.
R4 [6,7] are used to select register banks. To select a registers bank, refer to the following
examples and the table below:
(1) R4=00001100 and R4=01001100 point to the same register 0x0Ch. Since
0x0Ch is in the common space, Bit 6 and Bit 7 are meaningless.
(2) R4=10111100 points to the register 0x3C in Bank 2.
R4[7]Bk1
R4[6]Bk0
RAM Bank #
0
0
1
1
0
1
0
1
Bank 0
Bank 1
Bank 2
Bank3
R5 (Data Line I/O Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
-
-
-
-
-
-
1
0
D- or PS/2 D+ or PS/2
R5 [0]
D+ line register or PS/2 clock interface register.
R5 [1]
D- line register or PS/2 data interface register.
These two bits are BOTH writable and readable when the MCU is operating under PS/2
mode. But under USB Mode, these two bits cannot be accessed.
R5 [2~7] General purpose registers.
R6 (Port 6 I/O Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
P67
P66
P65
P64
P63
P62
P61
P60
R7 (Port 7 I/O Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
P77
P76
P75
P74
P73
P72
P71
P70
R8 (Port 6 Wake-up Pin Selection Register) Default Value: (0B_1111_1111)
7
6
5
4
3
2
1
0
/Wu87
/wu86
/Wu85
/Wu84
/Wu83
/Wu82
/Wu81
/Wu80
This specification may change without further notice.
2004/4/28 V1.1
12
EM78M612
Universal Serial Bus Microcontroller Series
R8 [0 ~ 7] Select which of the Port 6 pins are to be defined to wake-up the MCU from sleep
mode. When the state of the selected pins changes during sleep mode, the
MCU will wake-up and execute the next instruction automatically.
1: Disable the wake-up function
0: Enable the wake-up function
R9 (Port 7 Wake-up Pin Selection Register) Default Value: (0B_1111_1111)
7
6
5
4
3
2
1
0
/Wu77
/Wu76
/Wu76
/Wu74
/Wu73
/Wu72
/Wu71
/Wu70
R9 [0 ~ 7] Select which of the Port 7 pins are to be defined to wake-up the MCU from sleep
mode. When the state of the selected pins changes during sleep mode, the
MCU will wake-up and execute the next instruction automatically.
1: Disable the wake-up function
0: Enable the wake-up function
RA (High Pattern Counter Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
HP.7
HP.6
HP.5
HP.4
HP.3
HP.2
HP.1
HP.0
This register is used in pattern detecting application. If this function is disabled (IOCE[2] = 0),
the PDA function is disabled. RA register is also used as a general-purpose register.
RB (Low Pattern Counter Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
LP.7
LP.6
LP.5
LP.4
LP.3
LP.2
LP.1
LP.0
This register is used in pattern detecting application. If this function is disabled (IOCE[2] = 0),
the PDA function is disabled. RB register is also used as a general-purpose register.
RC (USB Application Status Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
EP0_W
EP0_R
EP1_R
0
Device_Resume
Host_Suspend
EP0_Busy
Stall
RC [0]
Stall flag. When MCU receives an unsupported command or invalid parameters
from host, this bit will be set to 1 by the firmware to notify the UDC to return a
STALL handshake. When a successful SETUP transaction is received, this bit is
cleared automatically. This bit is both readable and writable.
RC [1]
EP0 Busy flag. When this bit is equal to “1,” it indicates that the UDC is writing
data into the EP0’FIFO or reading data from it. During this time, the firmware will
avoid accessing the FIFO until UDC finishes writing or reading. This bit is only
readable.
This specification may change without further notice.
2004/4/28 V1.1
13
EM78M612
Universal Serial Bus Microcontroller Series
RC [2]
Host Suspend flag. If this bit is equal to 1, it indicates that USB bus has no traffic
for the specified period of 3.0 ms. This bit will also be cleared automatically when
a bus activity takes place. This bit is only readable.
RC [3]
Device Resume flag. This bit is set by firmware to general a signal to wake-up the
USB host and is cleared as soon as the USB Suspend signal becomes low. This
bit can only be set by firmware and cleared by the hardware.
RC [4]
Undefined Register. The default value is 0.
RC [5,6] EP0_R / EP1_R flag. These two bits inform the UDC to read the data written by
firmware from the FIFO. Then the UDC sends the data to the host automatically.
After UDC finishes reading the data from the FIFO, this bit is cleared
automatically.
Therefore, before writing data into the FIFO, the firmware will first check this bit to
prevent overwriting the existing data. These two bits can only be set by the
firmware and cleared by the hardware.
RC [7]
EP0_W flag. After the UDC completes writing data to the FIFO, this bit will be set
automatically. The firmware will clear it as soon as it gets the data from EP0’s
FIFO. Only when this bit is cleared that the UDC will be able to write a new data
into the FIFO.
Therefore, before the firmware can write a data into the FIFO, this bit must first be
set by the firmware to prevent UDC from writing data at the same time. This bit is
both readable and writable.
This specification may change without further notice.
2004/4/28 V1.1
14
EM78M612
Universal Serial Bus Microcontroller Series
RD (USB Application FIFO Address Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
0
0
0
UAD4
UAD3
UAD2
UAD1
UAD0
RD [0~4]
USB Application FIFO address registers. These five bits are the address pointer
of USB Application FIFO.
RD [5~7]
Undefined registers. The default value is zero.
RE (USB Application FIFO Data Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
UD7
UD6
UD5
UD4
UD3
UD2
UD1
UD0
RE (USB Application FIFO data register) contains the data in the register of which address
is pointed by RD.
RF (Interrupt Status Register ) Default Value: (0B_0000_0000)
7
6
Low
Signal_IF
High
Signal_IF
5
4
Port 5 State USB Host
Change_IF Resume_IF
3
USB
Reset_IF
2
1
0
USB
Suspend_IF EP0_IF TCC_IF
RF [0]
TCC Overflow interrupt flag. It will be set while TCC overflows, and is cleared by
the firmware.
RF [1]
EndPoint Zero interrupt flag. It will be set when the EM78M612 receives Vender
/Customer Command to EndPoint Zero. This bit is cleared by the firmware.
RF [2]
USB Suspend interrupt flag. It will be set when the EM78M612 finds the USB
Suspend Signal on USB bus. This bit is cleared by the firmware.
RF [3]
USB Reset interrupt flag. It will be set when the host issues the USB Reset
signal.
RF [4]
USB Host Resume interrupt flag. It is set only under Dual Clock mode when the
USB suspend signal becomes low.
RF [5]
Port 5 State Change interrupt flag. It is set when the Port 5 state changes.
RF [6, 7]
High/Low signal Counter interrupt flag. These two flags are used for pattern
detecting application.
R10~R1F are General purpose registers. These registers can be used no matter what Bank
Selector is. There are 3 banks(BK0~BK2) R20~R3F General purpose registers, Select by
R4 [6 7].
This specification may change without further notice.
2004/4/28 V1.1
15
EM78M612
Universal Serial Bus Microcontroller Series
8.2.1.2 Operation Registers in Bank 1
The special purpose registers for special operation (R8S~RES), are located in Special
Purpose Register Bank 1. To access these registers, bank selector (R3[7]) must be set first.
These Bank 1 located registers serve special functions, such as; E2PROM, Plus Width
Modulation, and Analog to Digital Converter. These registers and special functions are
described in details in Sections 8.2.3, 8.9, and 8.10 respectively in this specification.
R8S ( PWM1 Duty Cycle Register) Default Value：(0B_0000_0000)
A specified values keeps the output of PWM1 stay at high in a Period.
R9S ( PWM2 Duty Cycle Register) Default Value：(0B_0000_0000)
A specified values keeps the output of PWM2 stay at high in a Period.
RAS (AD Channel Select Register)
Default Value：(0B_0000_0000)
7
6
5
4
3
2
1
0
ADC
Token_Bit
0
AD4
AD3
AD2
AD1
AD0
RAS [0]~[4]:AD Channel Selector
AD4
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
AD3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
AD2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
AD1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
This specification may change without further notice.
AD0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
Channel
Disable AD
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
I/O Port
Reserved
P61
P62
P63
P64
P65
P66
P67
P70
P71
P72
P73
P74
P75
P76
P77
2004/4/28 V1.1
16
EM78M612
Universal Serial Bus Microcontroller Series
RAS [6]
Token_Bit will be latched to high by hardware when USB bus is transferring
token packet. This bit reset by firmware only.
RAS [7]
AD Converter ready flag.
0->1：Start AD Converting.(Bit set by Firmware)
1->0： When AD finish Converting and moving digital data into AD Data
Register , this bit is Clear by Hardware.
P.S.: Hardware enable this function only at AD Channel Selector on the
functional I/O port.
RBS (AD MSB Data Register) AD Digital Data MSB 8 bits
7
6
5
4
3
2
1
0
Bit 9
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
This Register is Read only.
RCS (AD LSB Data Register) AD Digital Data LSB 2 bits
7
6
5
4
3
2
1
0
Bit 1
Bit 0
-
-
-
-
-
-
This Register is Read only.
RES (EEPROM Mode Select Register)
Command Value
Default Value ( 0B_0000_0000)
Action
Execution Time
0B_0000_0000
Read
1ms
0B_0000_0001
Write
9ms
0B_0000_0010
Erase
128ms
0B_0000_0011
Disable
N.A.
This specification may change without further notice.
2004/4/28 V1.1
17
EM78M612
Universal Serial Bus Microcontroller Series
8.2.1.3 Control Registers in Bank 0
Special purpose registers for special control purposes are also available. Except for the
Accumulator (A), these registers must be read and written by special instructions. One of
these registers, CONT, can only be read by the instruction "CONTR" and written by
"CONTW" instruction. The remaining special control registers can be read by the instruction
"IOR" and written by the instruction "IOW."
The following paragraphs only describe the general functions of the control registers. For
more detailed description, refer to Sections 8.8 to 8.10 of this spec.
A (Accumulator Register)
The accumulator is an 8-bit register that holds operands and results of arithmetic
calculations. It is not addressable.
CONT (Control Register) Default Value: (0B_0011_1111)
7
6
5
4
3
2
1
0
0
/INT
TSR2
TSR1
TSR0
PSR2
PSR1
PSR0
[NOTE] The CONT register can be read by the instruction "CONTR" and written by the
instruction “CONTW."
CONT [0~2] WatchDog Timer prescaler bits. These three bits are used as the prescaler of
WatchDog Timer.
CONT [3~5] TCC Timer prescaler bits.
The relationship between the prescaler value and these bits are as shown below:
PSR2/TSR2
PSR1/TSR1
PSR0/TSR0
0
0
0
1: 2
1: 1
0
0
1
1: 4
1: 2
0
1
0
1: 8
1: 4
0
1
1
1: 16
1: 8
1
0
0
1: 32
1: 16
1
0
1
1: 64
1: 32
1
1
0
1: 128
1: 64
1
1
1
1: 256
1: 128
This specification may change without further notice.
TCC Rate
WDT Rate
2004/4/28 V1.1
18
EM78M612
Universal Serial Bus Microcontroller Series
CONT [6]
Interrupt enable control bit. This bit toggles Interrupt function between enable
and disable. It is set to 1 by the interrupt disable instruction "DISI" and reset by
the interrupt enable instructions "ENI" or "RETI."
0: Enable the Interrupt function.
1: Disable the Interrupt function.
CONT [7]
Undefined register. The default value is one.
IOC5 ~IOC7 (I/O Port [Port 5 ~ Port 7] Direction Control Registers
Each bit controls the I/O direction of three I/O ports respectively. When these bits are set to
1, the relative I/O pins become input pins. Similarly, the I/O pins becomes outputs when the
relative control bits are cleared.
1: Input direction.
0: Output direction.
IOC5 (Data Line I/O Control Register) Default Value: (0B_0000_0011)
7
6
5
4
3
2
1
0
0
0
0
0
0
0
I/O
I/O
IOC5 [2~7] Undefined registers. The default value is 0.
IOC6 (Port 6 I/O Control Register) Default Value: (0B_1111_1111)
7
6
5
4
3
2
1
0
P67
P66
P65
P64
P63
P62
P61
1
IOC6 [0]
This bit is always 1. This is because P60 can only be used as an input pin.
IOC7 (Port 7 I/O Control Register) Default Value: (0B_1111_1111)
7
6
5
4
3
2
1
0
P77
P76
P75
P74
P73
P72
P71
P70
This specification may change without further notice.
2004/4/28 V1.1
19
EM78M612
Universal Serial Bus Microcontroller Series
IOC8 (Sink Current Control Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
0
0
Sink1.1
Sink1.0
0
0
Sink0.1
Sink0.0
IOC8 [0,1][4,5] are P70/P71 sink current control registers. Four levels are offered for
selection:
Sink0.1/1.1
Sink0.0/1.0
Sink Current
0
0
3mA±10%
0
1
6mA±10%
1
0
12mA±10%
1
1
30mA±10%
The default current after Power-on reset is 3mA.
IOC9 (Pattern Detecting Application Control Register) Default Value：(0B_0111_0000)
7
0
6
Sample
Time.2
5
Sample
Time.1
4
Sample
Time.0
3
2
1
0
0
DB.2
DB.1
DB.0
IOC9 [0~2] Deboucing control registers. This is used for Pattern Detecting Application.
There are seven degrees available to debounce the input signal noise.
IOC9 [4~6] Sample time selection registers. This is used for Pattern Detecting Application.
The default value is 111.
Sample
Time.2
Sample
Time.1
Sample
Time.0
Sample Rate
( Divide the frequency of external oscillator by )
0
0
0
÷1
0
0
1
÷2
0
1
0
÷4
0
1
1
÷8
1
0
0
÷ 16
1
0
1
÷ 32
1
1
0
÷ 64
1
1
1
÷ 128
IOC9[3&7] Undefined register. The default value is Zero.
This specification may change without further notice.
2004/4/28 V1.1
20
EM78M612
Universal Serial Bus Microcontroller Series
IOCA (Operation Mode Control Register) Default Value: (0B_1100_0000)
7
6
5
4
3
2
1
0
Dual_Frq.1
Dual_Frq.0
0
0
0
0
PS/2
USB
IOCA [0,1] These two bits are used to select the operation mode. EM78M612 can
auto-detect the type of port device being attached. After identifying the port, the
firmware will set these two bits to enter into a proper operation mode. The
definition of these two control registers is described in the table below.
IOCA[1]
IOCA[0]
Operation Mode
0
0
Detect Mode
0
1
USB Mode
1
0
PS/2 Mode
1
1
USB Test Mode
IOCA [2~5] Undefined registers. The default value is 0.
IOCA [6,7]
Select the operation frequency in Dual Clock mode. Four frequencies are
available and can be chosen as Dual Clock mode for running the MCU
program.
Dual_Frq.1
Dual_Frq.0
Frequency
0
0
500Hz
0
1
4kHz
1
0
32kHz
1
1
256kHz
IOCB (Port 6 Pull-Low Control Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
PL67
PL66
PL65
PL64
PL63
PL62
PL61
-
IOCB [0~7]
Select whether the 15K Ohm pull-low resistor of Port 6 individual pin is
connected or not.
1: Enable the pull-low function.
0: Disable the pull-low function.
P60 without Pull low Resistor.
IOCC (Port 6 Pull-High Control Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
PH67
PH66
PH65
PH64
PH63
PH62
PH61
-
IOCC [0~7]
Select whether the 200K Ohm pull-high resistor of Port 6 individual pin is
connected or not.
This specification may change without further notice.
2004/4/28 V1.1
21
EM78M612
Universal Serial Bus Microcontroller Series
1: Enable the pull-high function.
0: Disable the pull-high function.
P60 without Pull high Resistor
IOCD (Port 7 Pull-High Control Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
PH77
PH76
PH75
PH74
PH73
PH72
PH71
PH70
IOCD [0~7]
Select whether the 200K Ohm pull-high resistor of Port 7 individual pin is
connected or not.
1: Enable the pull-high function.
0: Disable the pull-high function.
IOCE (Special Function Control Register) Default Value: (0B_1111_0000)
7
6
5
4
3
2
1
0
/Dual clock
/WUE
WTE
RUN
0
PDA
NA
NA
IOCE [2]
Pattern Detecting Application Enable Bit. This bit enables the Pattern
Detecting function which is used in the Serial Signal Transmission. When this
feature is enabled, P60 becomes a serial input pin allowing one pattern
detecting block, a counter, and two comparators to function.
1: enable
0: Disable
IOCE [3]
Undefined register. The default value is zero.
IOCE [4]
Run bit. This bit can be cleared by the firmware and set during power-on, or
by the hardware at the falling edge of wake-up signal. When this bit is cleared,
the clock system is disabled and the MCU enters into power down mode. At
the transition of wake-up signal from high to low, this bit is set to enable the
clock system.
1: Run mode. The EM78M612 is working normally.
0: Sleep mode. The EM78M612 is in power down mode.
IOCE [5]
WatchDog Timer enable bit. The bit disable/enables the WatchDog Timer.
1: Enable WDT.
0: Disable WDT.
[NOTE] If the Code Option WTC bit is "0,” WDT is always disabled.
IOCE [6]
Enable the wake-up function as triggered by port-change. This bit is set by
UDC.
1: Disable the wake-up function.
0: Enable the wake-up function.
This specification may change without further notice.
2004/4/28 V1.1
22
EM78M612
Universal Serial Bus Microcontroller Series
IOCE [7]
Dual clock Control bit. This bit is used to select the frequency of system clock.
When this bit is cleared, the MCU will run on very low frequency save power
and the UDC will stop working.
1: Selects EM78M612 to run on normal frequency.
0: Selects to run on slow frequency.
IOCF (Interrupt Mask Register)
7
Low
Signal_IE
6
5
Default Value: (0B_0000_0000)
4
High
Port 5 State USB Host
Signal _IE Change_IE Resume_IE
3
2
1
0
USB
Reset_IE
USB
Suspend_IE
EP0_IE
TCC_IE
IOCF [0~7] TCC / EP0 / USB Suspend / USB Reset / USB Host Resume / Port 5 State
Change / High Signal / Low Signal interrupt enable bits. These eight bits
respectively control the function of TCC interrupt, EP0 interrupt, USB Suspend
interrupt, USB Reset interrupt, USB Host Resume interrupt, Port5 State
Change interrupt, High pattern counter interrupt and Low pattern counter
interrupt. Individual interrupt is enabled by setting its associated control bit in
the IOCF to "1".
1: Enable Interrupt.
0: Disable Interrupt.
Only when the global interrupt is enabled by the ENI instruction that the individual interrupt
will work. After DISI instruction, any interrupt will not work even if the respective control bits
of IOCF are set to 1.
The USB Host Resume Interrupt works only under Dual clock mode. This is because when
the MCU is under sleep mode, it will be waked up by the UDC Resume signal automatically.
This specification may change without further notice.
2004/4/28 V1.1
23
EM78M612
Universal Serial Bus Microcontroller Series
8.2.1.4 Control Registers in Bank 1
Bank 1 offers more of the special purpose control registers. To write or read these registers,
the bank selector (R3[7]) must be initially set to 1. For more detailed description of these
registers, refer to Sections 8.8 to 8.10 of this spec.
IOC8S (PWM Control Register)
Default Value：(0B_0000_0111)
7
6
5
4
3
2
3
2
PEN2
PEN1
-
-
-
PS2
PS1
PS0
IOC8S [0~2] PWM Clock Prescaler
Fosc = 6MHz (No matter Xtal is 6MHz or 12MHz)
PS2
0
0
0
0
1
1
1
1
PS1
0
0
1
1
0
0
1
1
PS0
0
1
0
1
0
1
0
1
Clock(Hz)
Fosc/3
Fosc/6
Fosc/12
Fosc/24
Fosc/48
Fosc/96
Fosc/192
Fosc/384
Period/255
0.5us
1us
2us
4us
8us
16us
32us
64us
IOC8S [6] PWM1 Enable Bit
0:Disable
1:Enable
IOC8S [7] PWM2 Enable Bit
0:Disable.
1:Enable
IOCAS (AD Control Register) Default Value：(0B_0000_0000)
7
6
5
4
3
2
1
0
-
-
-
-
-
-
ADPS1
ADPS0
IOCAS [0,1]:AD Clock Prescaler
ADPS1
ADPS0
AD Clock Source
Conversion Rate
0
0
1
1
0
1
0
1
RC
RC/2
RC/4
RC/8
20K
10K
5K
2.5K
This specification may change without further notice.
2004/4/28 V1.1
24
EM78M612
Universal Serial Bus Microcontroller Series
8.2.2 USB Application FIFOs
For USB Application, EM78M612 provides an 8-byte First-In-First-Out (FIFO) buffer for each
endpoint. The buffer cannot be accessed directly. However, a corresponding Data Byte
Pointer register for each endpoint is made available to address the individual byte of the
FIFO buffer. The content of the individual byte will map to a special register.
8.2.3 E2PROM
Four bytes of E2PROM are located in the IOCC ~ IOCF of control register Bank 1. The
stored data of E2PROM are not erased when the power is off and can be read and rewritten
by firmware. In some special case of applications, for example, cordless mouse controller,
E2PROM can store important data, such as the cordless mouse’s device identification
number.
A control register, RES (address : 0x0E in Bank1) controls the E2PROM, that is, to read,
write, or to erase the data from E2PROM. Writing a command into this register will execute
an action to E2PROM. The command value is defined in the following table. Note that there
is an execution time lapse for each command. Before writing the next command into the
control register, allow enough time for the E2PROM to finish processing the previous
command.
Command Value
8.3
Action
Execution Time
0B_0000_0000
Read
1ms
0B_0000_0001
Write
9ms
0B_0000_0010
Erase
128ms
0B_0000_0011
Disable
N/A
I/O Ports
The EM78M612 has up to fifteen General Purposes I/O pins, which are classifies into two
port groups; Port 6 and Port 7. Each pin has an internal resistor that can be individually
selected by user. Notice that Pin 60 is a input only pin.The following describes the important
features of EM78M612 I/O pins.
8.3.1 Programmable Large Current
Port 7 has two pins; P70 and P71 that can drive large current of up to 30mA. The range of
driving current is from 3mA to 30mA, which is programmable. Use IOC8 [0,1] and IOC8 [4,5]
to control the sink current of P70/P71. The default current is 3mA.
This specification may change without further notice.
2004/4/28 V1.1
25
EM78M612
Universal Serial Bus Microcontroller Series
8.3.2 Wakeup by Port Change Function
Each of the GPIO pins in Port 6 and Port 7 can wakeup the MCU through signal change
from input pin. This function is used to wake-up the MCU automatically from sleep mode. It
also supports the remote wake-up function for USB application.
Any of the Individual pins of Port 6 and Port 7 can be defined to wakeup the MCU by setting
their respective bits, R8 and R9.
8.4
USB Application
EM78M612 is specially designed for USB device application and has many powerful
functions that help the firmware to free itself from complex situation in various aspects of
USB application.
8.4.1 Auto-Detect PS/2 or USB Mode
When the EM78M612 is connected to the bus, it will auto-detect and identify which type of
bus (USB or PS/2) it is connected to. The conditions that influence auto-detect function are
described below:
1. After a Power-on reset, the initial value of IOCA [0,1] is 0b00. Thus the operation
mode is “Detect mode” and the D+ and D- I/O pins are internal pulled high by 200K
Ohm to VDD.
2. The firmware checks the state of R5 [0,1]. If the state with which these two bits is
0x00, set the IOCA [0] to “1” to define the “USB mode.” Otherwise, set the IOCA [1]
to “1,” to define “PS/2 mode.”
3. When the operation mode is defined as “USB mode,” the D- I/O pin is internal pulled
high by a 1.5K Ohm resistor to 3.3V, which is output from a built-in regulator.
4. If the operation mode is in “PS/2 mode,” both of the PS/2 interface I/O pins are
internal pulled high by a 4.7K Ohm resistor to VDD.
{NOTE] If the auto-detect function is not used, the firmware should set the operation mode,
either in USB mode or PS/2 mode, at the beginning of program.
An additional mode, “USB Test Mode” is also available. This mode has no load on D+ and
D- I/O pins, and can only be used in USB Application case. Therefore, an external 1.5K Ohm
resistor is needed to pull up D- I/O pin to 3.3V.
Under “PS/2 mode,” both PS/2 pins are programmed to generate an interrupt. After setting
the Port 5 State change to Interrupt Enable bit, the MCU will interrupt while the state of these
two pins changes.
This specification may change without further notice.
2004/4/28 V1.1
26
EM78M612
Universal Serial Bus Microcontroller Series
8.4.2 USB Device Controller
The USB Device Controller (UDC) built-in in the EM78M612 can interpret the USB Standard
Command and response automatically without involving firmware. The embedded Series
Interface Engine (SIE) handles the serialization and deserialization of actual USB
transmission. Thus, a developer can concentrate his efforts more in perfecting the device
actual functions and spend less energy in dealing with USB transaction.
The UDC handles and decodes most Standard USB commands defined in the USB
Specification Rev1.1. If UDC receives an unsupported command, it will set a flag to notify
MCU the receipt of such command. The Standard Commands that EM78M612 supports
includes; Clear Feature, Get Configuration, Get Interface, Get Status, Set Address, Set
Configuration, Set Feature, and Set Interface.
Each time UDC receives a USB command, it writes the command into EP0’s FIFO. Only
when it receives unsupported command that the UDC will notify the MCU through interrupt.
Therefore, EM78M612 is very flexible under USB application because the developer can
freely choose the method of decoding the USB command as dictated by different situation.
8.4.3 Device Address and Endpoints
EM78M612 supports one device address, two endpoints, EP0 for control endpoint, and EP1
for interrupt endpoint. Sending data to USB host in EM78M612 is very easy. Just write data
into EP’s FIFO, then set flag, and the UDC will handle the rest. It will then confirm that the
USB host has received the correct data from EM78M612.
8.5
Reset
The EM78M612 provides three types of reset: (1) Power-on Reset, (2) WatchDog Reset,
and (3) USB Reset.
8.5.1 Power-On Reset
Power-on Reset occurs when the device is attached to power and a reset signal is initiated.
The signal will last until the MCU becomes stable. After a Power-on Reset, the MCU enters
into following predetermined states (see below), and then, it is ready to execute the program.
a. The program counter is cleared.
b. The TCC timer and WatchDog timer are cleared.
c. Special registers and Special Control registers are all set to initial value.
The MCU also has a low voltage detector that detects low output power condition.
Whenever the output voltage of the 3.3V regulator decreases to below 2.2V, a reset signal is
set off.
This specification may change without further notice.
2004/4/28 V1.1
27
EM78M612
Universal Serial Bus Microcontroller Series
8.5.2 WatchDog Reset
When the WatchDog timer overflows, it causes the WatchDog to reset. After it resets, the
program is executed from the beginning and some registers will be reset. The UDC however,
remains unaffected.
8.5.3 USB Reset
When UDC detects a USB Reset signal on USB Bus, it interrupts the MCU, then proceed to
perform the specified process that follows.
8.6
Power Saving Mode
The EM78M612 provides two options of power saving modes for energy conservation, i.e.,
Power Down mode, and Dual Clock mode.
8.6.1 Power Down Mode
The EM78M612 enters into Power Down mode by clearing the RUN register (IOCE[4]).
During this mode, the oscillator is turned off and the MCU goes to sleep. It will wake up
when signal from USB host is resumed, or when the WatchDog resets, or the input port state
changes.
If the MCU wakes up when I/O port status changes, I/O port direction should be set at input,
then the port state is read. For example:
:
// Set the Port 6 to input port
MOV
A , 0XFF
IOW
PORT6
// Read the state of Port 6
MOV
PORT6, PORT6
// Clear the RUN bit
IOR
0XE
AND
A , 0B11101111
IOW
0XE
:
:
If the MCU is awaken by a USB Resume signal, the next instruction will be executed, and
one flag, RC[3] will be set to 1.
8.6.2 Dual Clock Mode
The EM78M612 has one internal oscillator for power saving application. Clearing the Bit
IOCE [7] will enable the low frequency oscillator. At the same time, the external oscillator will
be turned off. Then the MCU will run under very low frequency to conserve power. Four
types of frequency are available for selection in setting Bits IOCA [6, 7].
This specification may change without further notice.
2004/4/28 V1.1
28
EM78M612
Universal Serial Bus Microcontroller Series
The USB Host Resume Interrupt can only be used in this mode. If this interrupt is enabled,
the MCU will be interrupted when the USB Suspend signal is detected on USB Bus.
8.7
Interrupt
The EM78M612 has two interrupt vectors, one is in 0x0001, and the other is in 0x000A.
When an interrupt occurs while the MCU is running, it will jump to the interrupt vector
(0x0001 or 0x000A) and execute the instructions sequentially from interrupt vector. RF is the
interrupt status register that records the interrupt status in the relative flags/bits.
The interrupt condition could be one of the following:
1. TCC Overflow
When the Timer Clock / Counter Register (R1) overflows, the
status flag RF[0] will be set to 1. Its interrupt vector is 0X0001.
2. EP0 Interrupt
When the UDC successfully received a setup transaction from
host to EndPoint0, the status flag RF[1] will be set to 1. Its
interrupt vector is 0X000A.
3. USB Suspend
When UDC detects a USB Suspend signal on USB bus, the
status flag RF[2] will be set to 1. Its interrupt vector is 0X000A.
4. USB Reset
When the UDC detects a USB Reset signal on USB bus, the
status flag RF[3] will be set to 1. Its interrupt vector is 0X000A.
5. USB Host Resume
When UDC detects that the USB bus has left the Suspend
condition, the status flag RF[4] will be set to 1. Its interrupt vector
is 0X000A.
6. Port 5 State Change
When the input signals in Port 5 changes, the status flag RF[5]
will be set to 1. Its interrupt vector is 0X0001.
7. High Pattern Detecting Interrupt Conditions If the Pattern Detecting Application function
is enabled, there will be three conditions with which interruption is
generated, and the status flag RF[6] is set to 1, Its interrupt vector
is 0X0001.
a) P.60 turns to low, and the Pattern Counter value bigger than
RA register value.
b) P.60 stays at high, and Pattern Counter value equal 0XFF.
c) P.60 turns to low and Pattern Counter value bigger than
0XFF.
This specification may change without further notice.
2004/4/28 V1.1
29
EM78M612
Universal Serial Bus Microcontroller Series
8. Low Pattern Counter Interrupt Conditions If the Pattern Detecting Application function is
enabled, there will be three conditions with which interruption is
generated and the status flag RF[7] is set to 1. Its interrupt vector
is 0X0001.
a) P.60 turns to high, and Pattern Counter value bigger than RB
register value.
b) P.60 stays low, and Pattern Counter value equal 0XFF.
c) P.60 turns to high, and Pattern Counter value bigger than
0XFF.
IOCF is an interrupt mask register which can be set individually bit by bit. While their
respective bit is written to 0, the hardware interrupt will inhibit, that is, the EM78M612 will not
jump to the interrupt vector to execute instructions. But the interrupt status flags still records
the conditions no matter whether the interrupt is masked or not. The interrupt status flags
must be cleared by firmware before leaving the interrupt service routine and enabling
interrupt.
The global interrupt is enabled by the ENI (RETI) instruction and is disabled by the DISI
instruction.
8.8
Pattern Detecting Application (PDA)
8.8.1 Function Description
This function is designed for the serial signal transmission, e.g., the transmission between a
wireless device and its receiver box. The EM78M612 has a built-in Pattern Detecting
Application block that ensures the EM78M612 supports wireless devices, such as receiver
box controller for a wireless mouse.
Pattern Detecting Application (PDA) can calculate the length of one pattern and interrupt the
MCU while the serial signal is transiting from high to low (or vise-versa). Then the MCU
reads the length value from a specified register.
8.8.2 Control Register
RA (High Pattern Counter Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
HP.7
HP.6
HP.5
HP.4
HP.3
HP.2
HP.1
HP.0
This register is used in pattern detecting application. If this function is disabled (IOCE[2] = 0),
the PDA function is disabled. RA register is also used as a general-purpose register.
This specification may change without further notice.
2004/4/28 V1.1
30
EM78M612
Universal Serial Bus Microcontroller Series
RB (Low Pattern Counter Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
LP.7
LP.6
LP.5
LP.4
LP.3
LP.2
LP.1
LP.0
This register is used in pattern detecting application. If this function is disabled (IOCE[2] = 0),
the PDA function is disabled. RB register is also used as a general-purpose register.
IOC9 (Pattern Detecting Application Control Register) Default Value：(0B_0111_0000)
7
6
5
4
3
2
1
0
0
Sample
Time.2
Sample
Time.1
Sample
Time.0
0
DB.2
DB.1
DB.0
IOC9 [0~2] Deboucing control registers. This is used for Pattern Detecting Application.
There are seven degrees available to debounce the input signal noise.
IOC9 [4~6] Sample time selection registers. This is used for Pattern Detecting Application.
The default value is 111.
Sample
Time.2
0
Sample
Time.1
0
Sample
Time.0
0
Sample Rate
( Divide the frequency of external oscillator by )
0
0
1
÷2
0
1
0
÷4
0
1
1
÷8
1
0
0
÷ 16
1
0
1
÷ 32
1
1
0
÷ 64
1
1
1
÷ 128
÷1
IOC9[3&7] Undefined register. The default value is Zero.
The PDA includes an enable control bit, an input pin (P60), a prescaler, a Pattern Detecting
block, two special register (RA and RB), and two interrupts (high pattern counter interrupt
and low pattern counter interrupt).
To use this function, the enable control bit, IOCE[2] has to be set first. Otherwise the P60
will just be treated as an input only pin and the RA/RB as general purpose register.
As long as the IOCE[2] control bit is set to 1 and the P60 is set as input pin, the Pattern
This specification may change without further notice.
2004/4/28 V1.1
31
EM78M612
Universal Serial Bus Microcontroller Series
Detecting block will start to sample the P60 input signal and measure the high pulse or low
pulse width. After detecting the transition of this signal and debouncing, the value of the
counter will be loaded into the RA (if the signal is transiting from high to low) or RB (if the
signal is transiting from low to high), and the counter is cleared to start counting from zero.
Two interrupts are supported individually by RA and RB. After the PDA function is enabled
(by setting IOCE[2] to 1), a default value is written to the High Pattern counter register and
Low Pattern counter register. Then define the corresponding interrupt enable bits (IOCF[6]
and IOCF[7]). When the counter value of one “H” pattern is bigger than the RA default value,
then the High Pattern Detecting interrupt will be generated. Similarly, if the counter value of
one “L” pattern is bigger than the RB default value, the Low Pattern Detecting interrupt will
occur. Then, the EM78M612 will be notified that one successful pattern is received from P60.
If these two interrupts are not used, they can be masked. The new counter value of a pattern
will still be loaded to the RA and RB. The firmware must be made to poll and determines any
changes to the value of these two registers.
The sample clock is programmable with 8 frequencies to choose from.
8.9
Pulse Width Modulation (PWM)
8.9.1 Function Description
In PWM mode, both of PWM1 (P64) and PWM2 (P65) produce up to a 8-bit resolution PWM
output. PWM output has a duty cycle and keeps the output high.
The PWM Period is defined as 0xFF * Timer Counter Clock. The Timer Counter clock
source is controlled by Control Register IOC8S. For example; if the Clock source is 1MHz,
then the Period will be 255µ seconds.
Period = 255 * (1/Timer Counter Clock)
Period (0xFF * Clock)
Duty Cycle
Fig.8.9.2 The PWM Output Timing
The PWM duty cycle is defined by writing to the R8S/R9S Register for PWM1/PWM2.
Duty Cycle = R8S * (1/Timer Counter Clock) for PWM1
R9S * (1/Timer Counter Clock) for PWM2
This specification may change without further notice.
2004/4/28 V1.1
32
EM78M612
Universal Serial Bus Microcontroller Series
8.9.2 Control Register
R8S (PWM1 Duty Cycle Register)
A specified value keeps the output of PWM1 to remain at high within a Period.
R9S (PWM2 Duty Cycle Register)
A specified value keeps the output of PWM2 to remain at high within a Period.
IOC8S (PWM Control Register) Default Value: (0B_0000_0111)
7
6
5
4
3
2
1
0
PEN2
PEN1
-
-
-
PS2
PS1
PS0
IOC8S [0~2] PWM Clock Prescaler.
Fosc = 6MHz (No matter Xtal is 6MHz or 12MHz)
PS2
PS1
PS0
Clock(Hz)
0
0
0
Fosc/3
Period/255
0.5us
0
0
1
Fosc/6
1us
0
1
0
Fosc/12
2us
0
1
1
Fosc/24
4us
1
0
0
Fosc/48
8us
1
0
1
Fosc/96
16us
1
1
0
Fosc/192
32us
1
1
1
Fosc/384
64us
IOC8S [6,7] PWM1/PWM2 Enable Bit
0:Disable
1:Enable
8.10 Analog-To-Digital Converter (ADC)
8.10.1 Function Description
The Analog to Digital converter consists of a 5-bit analog multiplexer, one Control Register
(IOCAS), one AD Channel Select Register (RAS), and two data registers (RBS & RCS) for
10-bit resolution
The ADC module utilizes successive approximation to convert the unknown analog signal to
a digital value. The result is fed to the ADDATA. Input channels are selected by the analog
input multiplexer via the ADCS/RAS bits AD0~AD4.
This specification may change without further notice.
2004/4/28 V1.1
33
EM78M612
Universal Serial Bus Microcontroller Series
10-bit resolution: 0x00-00~0xC0-FF (0b11000000-11111111)
Start (0x00-00):
0 Vref~(1/1024)*Vref
Full (0xC0-FF):
(1023/1024)*Vref~Vref
Conversion Rate: 2.5K; 5K; 10K; & 20K
8.10.2 Control Register
RAS (AD Channel Select Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
ADC
Token
Bit
0
AD4
AD3
AD2
AD1
AD0
RAS [0~4]:AD Channel Selector
AD4
AD3
AD2
AD1
AD0
Channel
I/O Port
0
0
0
0
0
Disable AD
-
0
0
0
0
1
1
Reserved
0
0
0
1
0
2
P61
0
0
0
1
1
3
P62
0
0
1
0
0
4
P63
0
0
1
0
1
5
P64
0
0
1
1
0
6
P65
0
0
1
1
1
7
P66
0
1
0
0
0
8
P67
0
1
0
0
1
9
P70
0
1
0
1
0
10
P71
0
1
0
1
1
11
P72
0
1
1
0
0
12
P73
0
1
1
0
1
13
P74
0
1
1
1
0
14
P75
0
1
1
1
1
15
P76
1
0
0
0
0
16
P77
RAS [6] Token Bit. This bit is asserted when MCU receives or transmits USB transaction.
RAS [7] AD Converter ready flag.
0
1: Start AD Conversion (Set by firmware).
1
0: When AD finishes converting and has moved digital data into AD Data Register,
this bit will be Cleared by hardware.
[NOTE] Hardware can enable this function only at AD Channel Selector of the functional I/O
port. After Power-on reset, the initial value of this register is 0b0000 0000.
This specification may change without further notice.
2004/4/28 V1.1
34
EM78M612
Universal Serial Bus Microcontroller Series
RBS (AD MSB Data Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
Bit 9
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
AD Digital Data MSB 8 bits.
RCS (AD LSB Data Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
Bit 1
Bit 0
0
0
0
0
0
0
AD Digital Data LSB 2 bits.
IOCAS (AD Control Register) Default Value: (0B_0000_0000)
7
6
5
4
3
2
1
0
0
0
0
0
0
0
ADPS1
ADPS0
IOCAS [0,1]: AD conversion rate.
00: 256kHz
01: 128kHz
10: 64kHz
11: 32kHz
This specification may change without further notice.
2004/4/28 V1.1
35
EM78M612
Universal Serial Bus Microcontroller Series
9 Absolute Maximum Ratings
Symbol
Temperature under bias
Storage temperature
Input voltage
Output voltage
Min
Max
Unit
0
-65
-0.5
-0.5
70
150
6.0
6.0
ºC
ºC
V
V
10 DC Electrical Characteristic
(T = 0ºC ~70ºC, VDD=4.4~5.2V, VSS=0V)
Symble
Parameter
Condition
Min
Type Max
Unit
3.3V Regulator
VRag
Output voltage of 3.3v Regulator
VDD = 4.2V ~ 5.2V
3.0
3.3
3.6
V
VResetL
Low Power Reset detecting low Voltage
-
V
VResetH
Low Power Reset detecting high Voltage
-
V
MCU Operation
IIL
Input Leakage Current for input pins
VIN= VDD,VSS
-
-
±1
μA
VIHX
Clock Input High Voltage
OSCI
2.5
-
-
V
VILX
Clock Input Low Voltage
OSCI
-
-
1.0
V
ICC1
VDD operating supply current –
Normal frequency operation mode
Crystal type
Freq. = 6MHz
Output pins floating
-
-
10
mA
ICC2
VDD operating supply current –
Normal frequency operation mode
-
-
20
mA
ISB1
Operating supply current 1 –
Power down mode
-
-
50
μA
ISB2
Operating supply current 2 –
Low frequency mode
200
μA
-
V
Crystal type
Freq. = 12MHz
Output pins floating
All input and I/O pins at VDD
Output pins floating
WDT disabled
RC oscillation type
Freq. = 20kHz~50kHz
Output pins floating
-
-
GPIO Pins
VIH
Input High Voltage
Port 5
VIL
Input Low Voltage
Port 5
VOH
Output High Voltage
(Port5 & Port 6 & P72~P77), OSCO)
IDrive = 5.0mA
2.4
-
-
V
VOL
Output Low Voltage
(Port5 & Port 6 & P72~P77, OSCO)
ISink = 5.0mA
-
-
0.4
V
IPH
Input current with pull-high resister
The input pin with internal
pull-high resistor of Port6 or
Port7 is connected to VSS.
-
25
-
μA
IPL
Input current with pull-low resister
The input pin with internal
pull-low resistor of Port6 is
connected to VDD.
-
330
-
μA
This specification may change without further notice.
-
-
V
2004/4/28 V1.1
36
EM78M612
Universal Serial Bus Microcontroller Series
USB Interface
VOH
Static Output High
VOL
Static Output Low
VDI
Differential Input Sensitivity
VCM
2.8
-
3.6
V
-
-
0.3
V
0.2
-
-
V
Differential Input Command Mode Range
0.8
-
2.5
V
VSE
Single Ended Receiver Threshold
0.8
-
2.0
V
CIN
Transceiver Capacitance
-
-
20
pF
VRG
Output Voltage of Internal Regulator
3.0
-
3.6
V
IPH
Input current with pull-high resister
(D-)
USB operation Mode
USB operation Mode
mA
Programmable Large Current
ISink1
P70, P71 Output Sink Current
ISink2
P70, P71 Output Sink Current
ISink3
P70, P71 Output Sink Current
ISink4
P70, P71 Output Sink Current
VOUT = 0.4V,
IOC8[0,1] or IOC8[4,5] = 00
VOUT = 0.4V,
IOC8[0,1] or IOC8[4,5] = 01
VOUT = 0.4V,
IOC8[0,1] or IOC8[4,5] = 10
VOUT = 0.4V,
IOC8[0,1] or IOC8[4,5] = 11
-10%
3
+10%
mA
-10%
6
+10%
mA
-10%
12
+10%
mA
-10%
30
+10%
mA
-
-
Cycle
Internal Memory Cycle Time
TROM
Endurance of Program ROM
T = 25ºC,
Vpp=10V, VNN=-10V
1K
TEE
Endurance of E2PROM
T = 25ºC,
VDD = 4.4V ~ 5.25V
4K
This specification may change without further notice.
2004/4/28 V1.1
Cycle
37
EM78M612
Universal Serial Bus Microcontroller Series
© 2004 ELAN Microelectronics Corporation
All Rights Reserved
Printed in Taiwan, ROC, 04/2004
The contents of this specification are subject to change without notice. ELAN Microelectronics assumes no
responsibility for errors that may appear in this specification. ELAN Microelectronics makes no commitment
to update, or to keep current, the information contained in this specification. The products described herein
are not intended for use in life support appliances, devices, or systems. Use of ELAN Microelectronics
products in such applications are not supported and is prohibited.
NO PART OF THIS SPECIFICATION MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM OR BY
ANY MEANS WITHOUT THE EXPRESS WRITTEN PERMISSION OF ELAN MICROELECTRONICS.
ELAN
MICROELECTRONICS
CORPORATION
Headquarters:
Hong Kong Office:
No. 12, Innovation Road 1,
Science-based Industrial Park,
Hsinchu, Taiwan, R.O.C.
Tel: +886 3 5639977
Fax: +886 3 5639966
http://www.emc.com.tw
Rm. 1005B, 10/F Empire Centre
68 Mody Road, Tsimshatsui
Kowloon , HONG KONG
Tel: +852 2838-8715
Fax: +852 2838-0497
This specification may change without further notice.
2004/4/28 V1.1
38