STMICROELECTRONICS ST6391B1

ST6391, ST6392, ST6393
ST6395, ST6397, ST6399
DATA SHEET
USE IN LIFE SUPPORT DEVICES OR SYSTEMS MUST BE EXPRESSLY AUTHORIZED.
SGS-THOMSON PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF SGS-THOMSON Microelectronics.
As used herein :
1. Life support devices or systems are those which (a) are
intended for surgical implant into the body, or (b) support
or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided with the product, can be reasonably expected to
result in significant injury to the user.
2. A critical component is any component of a life support
device or system whose failure to perform can reasonably be expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
ST639x DATASHEET INDEX
Pages
ST6391, ST6392, ST6393
ST6395, ST6397, ST6399
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PIN DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ST639x CORE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MEMORY SPACES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INTERRUPT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
RESET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
WAIT & STOP MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ON-CHIP CLOCK OSCILLATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INPUT/OUTPUT PORTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TIMERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
HARDWARE ACTIVATED DIGITAL WATCHDOG FUNCTION . . . . . . . . . . . . . . . . . . .
SERIAL PERIPHERAL INTERFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-BIT PWM D/A CONVERTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AFC A/D COMPARATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DEDICATED LATCHES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ON-SCREEN DISPLAY (OSD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SOFTWARE DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PACKAGE MECHANICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ORDERING INFORMATION TABLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1
3
5
7
10
17
21
23
24
25
28
31
32
41
41
42
43
52
57
61
64
ST6391, ST6392, ST6393
ST6395, ST6397, ST6399

8-BIT HCMOS MCUs
FOR TV FREQUENCY SYNTHESIS WITH OSD
PRELIMINARY DATA
4.5 to 6V supply operating range
8MHz Maximum Clock Frequency
User Program ROM: Up to 20140 bytes
Reserved Test ROM:Up to
340 bytes
Data ROM:
User selectable size
Data RAM:
256 bytes
Data EEPROM:
Up to
384 bytes
42-Pin Shrink Dual in Line Plastic Package
Up to 23 software programmable general purpose Inputs/Outputs, including 2 direct LED
driving Outputs
1
PSDIP42
Two Timers each including an 8-bit counter with
a 7-bit programmable prescaler
Digital Watchdog Function
(Ordering Information at the end of the datasheet)
Serial Peripheral Interface (SPI) supporting
S-BUS/ I2C BUS and standard serial protocols
SPI for external frequency synthesis tuning
Up to Six 6-Bit PWM D/A Converters
AFC A/D converter with 0.5V resolution
Five interrupt vectors (IRIN/NMI, Timer 1 & 2,
VSYNC, PWR INT.)
DEVICE SUMMARY
DEVICE
ROM
(Bytes)
EEPROM
(Bytes)
On-chip clock oscillator
ST6391
16K
128
5 Lines by 15 Characters On-Screen Display
Generator with 128 Characters
ST6392
20K
128
ST6393
16K
128
ST6395
20K
384
ST6397
20K
384
ST6399
16K
128
All ROM types are supported by pin-to-pin
EPROM and OTP versions.
The development tool of the ST639x microcontrollers consists of the ST638x-EMU emulation
and development system to be connected via a
standard RS232 serial line to an MS-DOS Personal Computer.
October 1993
This is Preliminary information from SGS-THOMSON. Details are subject to change without notice.
1/64
ST6391,92,93,95,97,99
Figure 1. ST6393/97 Pin Configuration
DA0
DA1
DA2
DA3
DA4
DA5
PB1
PB2
AFC
PB4
PB5
PB6
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
VSS
1
2
3
4
5
6
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
V DD
PC0 (SCL)
PC1 (SDA)
PC2
PC3 (SEN)
PC4
PC5
PC6 (IRIN)
PC7
RESET
OSCout
OSCin
TEST
OSDOSCout
OSDOSCin
VSYNC
HSYNC
BLANK
B
G
R
VA00339
Figure 3. ST6391/95 Pin Configuration
Figure 2. ST6392/99 Pin Configuration
DA0
DA1
DA2
DA3
62.5kHz OUT
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PA0
PA1
PA2
PA3
PA4
PA5
PA6 (HD0)
PA7 (HD1)
VSS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
V DD
PC0 (SCL)
PC1 (SDA)
PC2
PC3 (SEN)
PC4 (PWRIN)
PC5
PC6 (IRIN)
PC7
RESET
OSCout
OSCin
TEST
OSDOSCout
OSDOSCin
VSYNC
HSYNC
BLANK
B
G
R
DA0
DA1
DA2
DA3
DA4
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PA0
PA1
PA2
PA3
PA4
PA5
PA6 (HD0)
PA7 (HD1)
VSS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Note 1. ST6395 only

V DD
PC0 (SCL)
PC1 (SDA)
PC2
PC3 (SEN)
(1)
PC4 (PWRIN )
PC5
PC6 (IRIN)
PC7
RESET
OSCout
OSCin
TEST
OSDOSCout
OSDOSCin
VSYNC
HSYNC
BLANK
B
G
R
VA00337
VA00340
2/64
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
ST6391,92,93,95,97,99
GENERAL DESCRIPTION
The ST639x microcontrollers are members of the 8bit HCMOS ST638x family, a series of devices specially oriented to TV applications. Different ROM size
and peripheral configurations are available to give
the maximum application and cost flexibility. All
ST639x members are based on a building block approach:a common core is surrounded by a combination of on-chip peripherals (macrocells) available
from a standard library. These peripherals are designed with the same Core technology providing full
compatibility and short design time. Many of these
macrocells are specially dedicated to TV applications. The macrocells of the ST639x family are: two
Timer peripherals each including an 8-bit counter
with a 7-bit software programmable prescaler
(Timer), a digital hardware activated watchdog
function (DHWD), a 14-bit voltage synthesis tuning
peripheral, a Serial Peripheral Interface (SPI), up
to six 6-bit PWM D/A converters, an AFC A/D converter with 0.5V resolution, an on-screen display
(OSD) with 15 characters per line and 128 characters (in two banks each of 64 characters). In addition the following memory resources are available:
program ROM (up to 20K), data RAM (256 bytes),
EEPROM (up to 384 bytes). Refer to pin configurations figures and to ST639x device summary (Table 1) for the definition of ST639x family members
and a summary of differences among the different
types.
3/64

ST6391,92,93,95,97,99
Figure 4. ST6391,92,93, 95,97,99Block Diagram
* Refer To Pin Configuration For Additional Information
TEST
IRIN/PC6
TEST
PORT A
PA0 - PA7 *
IR INTERRUPT
Input
PORT B
PB0 - PB7 *
PC2, PC4 - PC7 *
PC0 / SCL
PC1 / SDA
PC3 / SEN
PORT C
DATA ROM
USER SELECTABLE
USER PROGRAM
ROM
UP TO 20 kBytes
SERIAL PERIPHERAL
INTERFACE
DATA RAM
256 Bytes
TIMER 1
DATA EEPROM
384 Bytes
TIMER 2
DIGITAL
WATCHDOG/TIMER
PC
STACK
STACK
STACK
STACK
STACK
STACK
LEVEL 1
LEVEL 2
LEVEL 3
LEVEL 4
LEVEL 5
LEVEL 6
D / A Outputs
VSS
AFC
AFC Input
POWER SUPPLY
VDD
DA0 - DA5
8-BIT CORE
OSCILLATOR
OSCin
ON-SCREEN
DISPLAY
RESET
OSCout
R, G, B, BLANK
HSYNC, VSYNC
VR0 1753G
RESET
Table 1. Device Summary
ROM
RAM
EEPROM
(Bytes)
(Bytes)
(Bytes)
ST6391
16K
256
ST6392
20K
ST6393
COLOUR
LOW
POWER IN
RESET
PWRIN
SPI
62.5kHz EMULATING
CLK FREQ.
Pin
DEVICES
(kHz)
AFC
D/A
128
NO
5
3
NO
NO
62.5
NO
ST63E91
256
128
NO
4
3
YES
YES
62.5
YES
ST63E92
16K
256
128
YES
6
3
NO
NO
62.5
NO
ST63E93
ST6395
20K
256
384
NO
5
3
NO
YES
100
NO
ST63E95
ST6397
20K
256
384
YES
6
3
NO
NO
100
NO
ST63E97
ST6399
16K
256
128
NO
4
3
YES
YES
62.5
YES
ST63E99
DEVICE
4/64

PINS
PIN
ST6391,92,93,95,97,99
PIN DESCRIPTION
VDD and VSS. Power is supplied to the MCU using
these two pins. VDD is power and VSS is the ground
connection.
OSCin, OSCout. These pins are internally connected to the on-chip oscillator circuit. A quartz
crystal or a ceramic resonator can be connected
between these two pins in order to allow the correct operation of the MCU with various stability/cost trade-offs. The OSCin pin is the input pin,
the OSCout pin is the output pin.
RESET. The active low RESET pin is used to start
the microcontroller to the beginning of its program.
Additionally the quartz crystal oscillator will be disabled when the RESET pin is low to reduce power
consumption during reset phase (ST6392/99 only).
TEST. The TEST pin must be held at VSS for normal operation.
PA0-PA7. These 8 lines are organized as one I/O
port (A). Each line may be configured as either an
input with or without pull-up resistor or as an output
under software control of the data direction register. Pins PA4 to PA7 are configured as open-drain
outputs (12V drive). On PA4-PA7 pins the input
pull-up option is not available while PA6 and PA7
have additional current driving capability (25mA,
VOL:1V). PA0 to PA3 pins are configured as pushpull.
PB0-PB2, PB4-PB6. These 6 lines are organized
as one I/O port (B). Each line may be configured as
either an input with or without internal pull-up resistor or as an output under software control of the
data direction register.
PC0-PC7. These 8 lines are organized as one I/O
port (C). Each line may be configured as either an
input with or without internal pull-up resistor or as
an output under software control of the data direction register. Pins PC0 to PC3 are configured as
open-drain (5V drive) in output mode while PC4 to
PC7 are open-drain with 12V drive and the input
pull-up options does not exist on these four pins.
PC0, PC1 and PC3 lines when in output mode are
“ANDed” with the SPI control signals and are all
Open-drain. PC0 is connected to the SPI clock signal (SCL), PC1 with the SPI data signal (SDA)
while PC3 is connected with SPI enable signal
(SEN, used in S-BUS protocol). Pin PC4 and PC6
can also be inputs to software programmable edge
sensitive latches which can generate interrupts;
PC4 can be connected to Power Interrupt while
PC6 can be connected to the IRIN/NMI interrupt
line.
DA0-DA5. These pins are the six PWM D/A outputs of the 6-bit on-chip D/A converters. These
lines have open-drain outputs with 12V drive. The
output repetition rate is 31.25KHz (with 8MHz
clock).
AFC. This is the input of the on-chip 10 levels comparator that can be used to implement the AFC
function. This pin is an high impedance input able
to withstand signals with a peak amplitude up to
12V.
OSDOSCin, OSDOSCout. These are the On
Screen Display oscillator terminals. An oscillation
capacitor and coil network have to be connected to
provide the right signal to the OSD.
HSYNC, VSYNC. These are the horizontal and
vertical synchronization pins. The active polarity of
these pins to the OSD macrocell can be selected
by the user as ROM mask option. If the device is
specified to have negative logic inputs, then these
signals are low the OSD oscillator stops. If the device is specified to have positive logic inputs, then
when these signals are high the OSD oscillator
stops.
R, G, B, BLANK. Outputs from the OSD. R, G and
B are the color outputs while BLANK is the blanking output. All outputs are push-pull. The active polarity of these pins can be selected by the user as
ROM mask option.
62.5kHz OUT. This pin is available only on the
ST6392/99. The pin is an open drain (12V) output
at the frequency of 62.5kHz (with an 8MHz clock).
The pin can be used to drive the SGS-THOMSON
TEA5640 Chroma Processor. Refer to the
TEA5640 Data sheet for more information.
5/64

ST6391,92,93,95,97,99
Table 2. Pin Summary
Pin Function
Description
DA0 to DA5
Output, Open-Drain, 12V
AFC
Input, High Impedance, 12V
R,G,B, BLANK
Output, Push-Pull
HSYNC, VSYNC
Input, Pull-up, Schmitt Trigger
OSDOSCin
Input, High Impedance
OSDOSCout
Output, Push-Pull
TEST
Input, Pull-Down
OSCin
Input, Resistive Bias, Schmitt Trigger to Reset Logic Only
OSCout
Output, Push-Pull
RESET
Input, Pull-up, Schmitt Trigger Input
PA0-PA3
I/O, Push-Pull, Software Input Pull-up, Schmitt Trigger Input
PA4-PA5
I/O, Open-Drain, 12V, No Input Pull-up, Schmitt Trigger Input
PA6-PA7
I/O, Open-Drain, 12V, No Input Pull-up, Schmitt Trigger Input, High Drive
PB0-PB6
I/O, Push-Pull, Software Input Pull-up, Schmitt Trigger Input
PC0-PC3
I/O, Open-Drain, 5V , Software Input Pull-up, Schmitt Trigger Input
PC4-PC7
I/O, Open-Drain, 12V, No Input Pull-up, Schmitt Trigger Input
VDD, VSS
Power Supply Pins
62.5kHz OUT
Output, Open-Drain 12V
6/64

ST6391,92,93,95,97,99
ST639x CORE
The Core of the ST639x Family is implemented independently from the I/O or memory configuration.
Consequently, it can be treated as an independent
centralprocessor communicating with I/O and memory via internal addresses, data, and control busses.
The in-core communication is arranged as shown
in the following block diagram figure; the controller
being externally linked to both the reset and the oscillator, while the core is linked to the dedicated onchip macrocells peripherals via the serial data bus
and indirectly for interrupt purposes through the
control registers.
Registers
The ST639x Family Core has five registers and
three pairs of flags available to the programmer.
They are shown in Figure 5 and are explained in
the following paragraphs together with the program and data memory page registers.
Accumulator (A). The accumulator is an 8-bit general purpose register used in all arithmetic calculations, logical operations, and data manipulations.
The accumulator is addressed in the data space as
RAM location at the FFh address.
Accordingly, the ST639x instruction set can use
the accumulator as any other register of the data
space.
Figure 6. ST639x Core Programming Model
INDEX
REGISTER
b11
b7
X REG. POINTER
b0
b7
Y REG. POINTER
b0
SHORT
DIRECT
ADDRESSING
MODE
b0
b7
V REGISTER
b7
W REGISTER
b0
b7
ACCUMULATOR
b0
b0
PROGRAM COUNTER
SIX LEVELS
STACK REGISTER
NORMAL FLAGS
C
Z
INTERRUPT FLAGS
C
Z
NMI FLAGS
C
Z
VA000423
Figure 5. ST639x Core Block Diagram
7/64

ST6391,92,93,95,97,99
ST639x CORE (Continued)
Indirect Registers (X, Y). These two indirect registers are used as pointers to the memory locations
in the data space. They are used in the register-indirect addressing mode.These registers can be
addressed in the data space as RAM locations at
the 80h (X) and 81h (Y) addresses. They can also
be accessed with the direct, short direct, or bit direct addressing modes. Accordingly, the ST639x
instruction set can use the indirect registers as any
other register of the data space.
Short Direct Registers (V, W). These two registers are used to save one byte in short direct addressing mode. These registers can be addressed
in the data space as RAM locations at the 82h (V)
and 83h (W) addresses. They can also be accessed with the direct and bit direct addressing
modes. Accordingly, the ST639x instruction set
can use the short direct registers as any other register of the data space.
Program Counter (PC)
The program counteris a 12-bit register thatcontains
the address of the next ROM location to be processed by the core. This ROM location may be an opcode, an operand, or an address of operand. The
12-bit length allows the direct addressing of 4096
bytes in the program space. Nevertheless, if the program space contains more than 4096 locations, the
further program space can be addressed by using
the Program ROM Page Register. The PC value is
incremented, after it is read for the address of the
current instruction, by sending it through the ALU, so
giving the address of the next byte in the program.
To execute relative jumps the PC and the offset values are shifted through the ALU, where they will be
added, and the result is shifted back into the PC. The
program counter can be changed in the following
ways:
JP (Jump) instruction.... PC= Jump address
CALL instruction ........... PC=Call address
Relative Branch
instructions ................... PC=PC+offset
Interrupt........................ PC=Interrupt vector
Reset............................ PC=Reset vector
RET & RETI instructions............PC=Pop (stack)
Normal instruction ........ PC= PC+1
Flags (C, Z)
The ST639x Core includes three pairs of flags that
correspond to 3 different modes: normal mode, interrupt mode and Non-Maskable-Interrupt-Mode.
Each pair consists of a CARRY flag and a ZERO
flag. One pair (CN, ZN) is used during normal operation, one pair is used during the interrupt mode
(CI,ZI) and one is used during the not-maskable interrupt mode (CNMI, ZNMI).
The ST639x Core uses the pair of flags that corresponds to the actual mode: as soon as an interrupt
(resp. a Non-Maskable-Interrupt) is generated, the
ST639x Core uses the interrupt flags (resp. the NMI
flags) instead of the normal flags. When the RETI instruction is executed, the normal flags (resp. the interrupt flags) are restored if the MCU was in the normal
mode(resp. in the interrupt mode)before the interrupt.
Should be observed that each flag set can only be addressed in its own routine (Not-maskable interrupt,
normal interrupt or main routine). The interrupt flags
are not cleared during the context switching and so,
theyremain in the state they were at the exit of the last
routine switching.
The Carry flag is set when a carry or a borrow occurs during arithmetic operations, otherwise it is
cleared. The Carry flag is also set to the value of
the bit tested in a bit test instruction, and participates in the rotate left instruction.
The Zero flag is set if the result of the last arithmetic
or logical operation was equal to zero, otherwise it
is cleared.
The switching between these three sets is automatically performed when an NMI, an interrupt and
a RETI instructions occur. As the NMI mode is
automatically selected after the reset of the MCU,
the ST639x Core uses at first the NMI flags.
Figure 7. Stack Operation
PROGRAM COUNTER
STACK LEVEL 1
WHEN
RET OR RETI
OCCURS
STACK LEVEL 2
STACK LEVEL 3
WHEN CALL
OR
INTERRUPT REQUEST
OCCURS
STACK LEVEL 4
STACK LEVEL 5
STACK LEVEL 6
VA000424
8/64

ST6391,92,93,95,97,99
ST639x CORE (Continued)
Stack
The ST639x Core includes true LIFO hardware
stack that eliminates the need for a stack pointer.
The stack consists of six separate 12-bit RAM locations that do not belong to the data space RAM
area. When a subroutine call (or interrupt request)
occurs, the contents of each level is shifted into the
next level while the content of the PC is shifted into
the first level (the value of the sixth level will be
lost). When subroutine or interrupt return occurs
(RET or RETI instructions), the first level register is
shifted back into the PC and the value of each level
is shifted back into the previous level. These two
operating modes are described in Figure 7. Since
the accumulator, as all other data space registers,
is not stored in this stack the handling of this registers shall be performed inside the subroutine. The
stack pointer will remain in its deepest position, if
more than 6 calls or interrupts are executed, so
that the last return address will be lost. It will also
remain in its highest position if the stack is empty
and a RET or RETI is executed. In this case the
next instruction will be executed.
Memory Registers
The PRPR can be addressed like a RAM location
in the Data Space at the CAh address; nevertheless it is a write-only register that can not be accessed with single-bit operations. This register is
used to select the 2-Kbyte ROM bank of the Program Space that will be addressed. The number of
the page has to be loaded in the PRPR. The PRPR
is not cleared during the MCU initialization and
should therefore be defined before jumping out of
the static page. Refer to the Program Space description for additional information concerning the
use of this register. The PRPR is not modified
when an interrupt or a subroutine occurs.
Figure 8. Program ROM Page Register
PRPR
The DRBR can be addressed like a RAM location
in the Data Space at the E8h address, nevertheless it is write-only register that can not be accessed with single-bit operations. This register is
used to select the desired 64-byte RAM/EEPROM
bank of the Data Space. The number of the bank
has to be loaded in the DRBR and the instruction
has to point to the selected location as it was in the
0 bank (from 00h address to 3Fh address). This
register is undefined after Reset. Refer to the Data
Space description for additional information. The
DRBR register is not modified when a interrupt or a
subroutine occurs.
Figure 9. Data RAM Bank Register
DRBR
Data RAM Bank Register
(E8h, Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
The DRWR register can be addressedlike a RAM location in the Data Space at the C9h address, nevertheless it is write-only register that can not be
accessed with single-bit operations. This register is
used to move up and down the 64-byte read-only
data window (from the 40h address to 7Fh address
of the Data Space) along the ROM of the MCU by
step of 64 bytes. The effective address of the byte to
be read as a data in the ROM is obtainedby the concatenationof the 6 less significant bits of the address
given in the instruction (as less significant bits) and
the content of the DRWR (as most significant bits).
Refer to the Data Space description for additional information.
Figure 10. Data ROM Window Register
Program ROM Page Register
(CAh, Write Only)
DRWR
D7 D6 D5 D4 D3 D2 D1 D0
Data ROM Window Register
(C9h, Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
9/64

ST6391,92,93,95,97,99
MEMORY SPACES
The MCUs operate in three different memory
spaces: Stack Space, Program Space, and Data
Space. A description of these spaces is shown in
Figure 11.
Stack Space
The stack space consists of six 12 bit registers that
are used for stacking subroutine and interrupt return
addressesplus the current programcounterregister.
Program Space
The program space is physically implemented in
the ROM and includes all the instructions that are
to be executed, as well as the data required for the
immediate addressing mode instructions, the reserved test area and user vectors. It is addressed
thanks to the 12-bit Program Counter register (PC
register) and so, the ST639x Core can directly address up to 4K bytes of Program Space. Nevertheless, the Program Space can be extended by the
addition of 2-Kbyte ROM banks as it is shown in
Figure 13 in which a 20K bytes memory is described. These banks are addressed by pointing to
the 000h-7FFh locations of the Program Space
thanks to the Program Counter, and by writing the
appropriate code in the Program ROM Page Register (PRPR) located at the CAh address of the
Data Space. Because interrupts and common subroutines should be available all the time only the
lower 2K byte of the 4K program space are bank
switched while the upper 2K byte can be seen as
static space. Table 3 gives the different codes that
allows the selection of the corresponding banks.
Note that, from the memory point of view, the Page
1 and the Static Page represent the same physical
memory: it is only a different way of addressing the
same location. On the ST6392,95,97, a total of
2048, bytes of ROM have been implemented;
20140 are available as user ROM while 340 are reserved for testing.
Figure 12. ST639x 20K Bytes Program Space
Addressing Description
Program
counter
space
0000h
4FFFh
0FFFh
Static Page
Page 1
0800h
07FFh
Page 0
Page 1
Static Page
Page 9
0000h
Figure 11. ST639x Memory Addressing Description Diagram
STACK SPACE
PROGRAM SPACE
DATA SPACE
00 00h
000h
R AM / E EPROM
PROGRAM COUNTER
B AN KING AR EA
0-63
STACK LEVE L 1
ROM
STACK LEVE L 2
STACK LEVE L 3
03Fh
040h
D ATA R OM
STACK LEVE L 4
W IN D O W
STACK LEVE L 5
070h
080h
081h
082h
083h
084h
STACK LEVE L 6
07FFh
08 00h
X RE GISTER
Y R EGISTER
V RE GISTER
W R EGISTER
R AM
ROM
0C0 h
D ATA R OM
WI N D OW SELEC T
D ATA R AM
BAN K SELEC T
0FF0h
0FFFh
IN TER RU PT &
R ESET VEC TOR S
0FFh
AC C U MU LATOR
VR001568
10/64

ST6391,92,93,95,97,99
MEMORY SPACES (Continued)
interrupt driver in a (minor) part in the static page
(start and end), and in the second (major) part in
one dynamic page. If it is impossible to avoid the
writing of this register in interrupts drivers, an image of this register must be saved in a RAM location, and each time the program writes the PRPR it
writes also the image register. The image register
must be written first, so if an interrupt occurs between the two instructions the PRPR is not affected.
Figure 13. Program ROM Page Register
PRPR
Program ROM Page Register
(CAh, Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
PRPR0
PRPR1
PRPR2
PRPR3
Table 3. ST639x Program ROM Page Register
Coding
UNUSED
D7-D5. These bits are not used.
PRPR4-PRPR0. These are the program ROM
banking bits and the value loaded selects the corresponding page to be addressed in the lower part
of 4K program address space as specified in Table
3. This register is undefined on reset.
Note. The number of bits implemented depends
on the size of the ROM of the device. Only the
lower part of address space has been bankswitched because interrupt vectors and common
subroutines should be available all the time. The
reason of this structure is due to the fact that it is
not possible to jump from a dynamic page to another, unless jumping back to the static page,
changing contents of PRPR, and, than, jumping to
a different dynamic page.
Care is required when handling the PRPR as it is
write only. For this reason, it is not allowed to
change the PRPR contents while executing interrupts drivers, as the driver cannot save and than
restore its previous content. Anyway, this operation may be necessary if the sum of common routines and interrupt drivers will take more than 2K
bytes; in this case could be necessary to divide the
PRPR3
PRPR2
PRPR1
PRPR0
PC11
Memory
Page
X
X
X
X
1
Static
Page
(Page 1)
0
0
0
0
0
Page 0
0
0
0
1
0
Page 1
(Static
Page)
0
0
1
0
0
Page 2
0
0
1
1
0
Page 3
0
1
0
0
0
Page 4
0
1
0
1
0
Page 5
0
1
1
0
0
Page 6
0
1
1
1
0
Page 7
1
0
0
0
0
Page 8
1
0
0
1
0
Page 9
11/64

ST6391,92,93,95,97,99
MEMORY SPACES (Continued)
Table 4. ST639x Program ROM Map (up to 20K Bytes)
ROM Page
PAGE 0
Device Address
Description
0000h-007Fh
0080h-07FFh
Reserved
User ROM
0FFEh-0FFFh
User ROM
Reserved
Interrupt Vectors
Reserved
NMI Vector
Reset Vector
PAGE 2
0000h-000Fh
0010h-07FFh
Reserved
User ROM
PAGE 3
0000h-000Fh
0010h-07FFh
Reserved
User ROM
0000h-000Fh
Reserved
User ROM
0800h-0F9Fh
0FA0h-0FEFh
PAGE 1
“STATIC”
PAGE 4
0FF0h-0FF7h
0FF8h-0FFBh
0FFCh-0FFDh
0010h-07FFh
0010h-07FFh
Reserved
User ROM
PAGE 6
0000h-000Fh
0010h-07FFh
Reserved
User ROM
PAGE 7
0000h-000Fh
0010h-07FFh
Reserved
User ROM (End of 16K ST6391,93,99)
PAGE 8
0000h-000Fh
0010h-07FFh
Reserved
User ROM
0000h-000Fh
Reserved
User ROM (End of 20K ST6392,95,97)
PAGE 5
PAGE 9
0000h-000Fh
0010h-07FFh
12/64

ST6391,92,93,95,97,99
MEMORY SPACES (Continued)
Data Space
The instruction set of the ST639x Core operates on a specific space, named Data Space
tha t contains all the data necessary for the
processing of the program. The Data Space al-
lows the addressing of RAM (256 bytes for the
ST639x family), EEPROM (up to 384 bytes),
ST639x Core/peripheralregisters, and read-only
data such asconstantsand the look-up tables.
Figure 14. ST639x Data Space
Figure 15. ST639x Data Space (Continued)
b7
b0
b7
b0
RESERVED
TIMER 2 PRESCALER REGISTER
TIMER 2 COUNTER REGISTER
TIMER 2 STATUS CONTROL REG.
000h
DATA RAM/EEPROM/OSD
BANK AREA
03Fh
040h
DATA ROM
WINDOW AREA
X REGISTER
Y REGISTER
V REGISTER
W REGISTER
RESERVED
07Fh
080h
081h
082h
083h
084h
DA0 DATA/CONTROL REGISTER
DA1 DATA/CONTROL REGISTER
DA2 DATA/CONTROL REGISTER
DA3 DATA/CONTROL REGISTER
AFC, IR & OSD RESULT REGISTER
OUTPUTS CONTROL REGISTER
DA4 DATA/CONTROL REGISTER
DA5 DATA/CONTROL REGISTER
DATA RAM BANK REGISTER
DEDIC. LATCHES CONTROL REG.
EEPROM CONTROL REGISTER
SPI CONTROL REGISTER 1
SPI CONTROL REGISTER 2
OSD CHARAC. BANK SELECT REG.
DATA RAM
PORT A DATA REGISTER
PORT B DATA REGISTER
PORT C DATA REGISTER
RESERVED
PORT A DIRECTION REGISTER
PORT B DIRECTION REGISTER
PORT C DIRECTION REGISTER
RESERVED
INTERRUPT OPTION REGISTER
DATA ROM WINDOW REGISTER
PROGRAM ROM PAGE REGISTER
RESERVED
SPI DATA REGISTER
0BFh
0C0h
0C1h
0C2h
0C3h
0C4h
0C5h
0C6h
0C7h
0C8h
0C9h
0CAh
0CBh
0CCh
0CDh
ACCUMULATOR
0FEh
0FFh
OSD CONTROL REGISTERSLOCATED
IN PAGE 6 OF BANKED DATA RAM
0D1h
0D2h
0D3h
0D4h
0D5h
VERTICAL START ADDRESS REG.
HORIZONTALSTART ADDRESS REG.
VERTICAL SPACE REGISTER
HORIZONTAL SPACE REGISTER
BACKGROUND COLOUR REGISTER
GLOBAL ENABLEREGISTER
RESERVED
WATCHDOG REGISTER
0DFh
0E0h
0E1h
0E2h
0E3h
0E4h
0E5h
0E6h
0E7h
0E8h
0E9h
0EAh
0EBh
0ECh
0EDh
0F0h
RESERVED
RESERVED
TIMER 1 PRESCALER REGISTER
TIMER 1 COUNTER REGISTER
TIMER 1 STATUS/CONTROL REG.
0D9h
0DAh
0DBh
0DCh
0DDh
0D7h
0D8h
010h
011h
012h
013h
014h
017h
13/64

ST6391,92,93,95,97,99
MEMORY SPACES (Continued)
Data ROM Addressing. All the read-only data are
physically implemented in the ROM in which the Program Space is also implemented. The ROM therefore
containsthe programto be executedandalso the constants and the look-up tables neededfor the program.
The locationsof Data Space in which the differentconstants and look-up tables are addressed by the
ST639x Core can be considered as being a 64-byte
window through which it is possible to access to the
read-only data stored in the ROM. This window is located from the 40h address to the 7Fh address in the
Data space and allows the direct reading of the bytes
from the 000h address to the 03Fh address in the
ROM. All the bytes of the ROM can be used to store
either instructions or read-only data. Indeed,the window can bemoved by step of 64 bytes alongthe ROM
in writing the appropriate code in the Write-only Data
ROM Window register (DRWR, location C9h). The effective address of the byte to be read as a data in the
ROM is obtained by the concatenation of the 6 less
significant bits of the address in the Data Space (as
less significant bits) and the content of the DRWR (as
most significant bits). So when addressing location
40h of data space, and 0 is loaded in the DRWR, the
physical addressed location in ROM is 00h.
Note. The data ROM window cannot address windows above the 16k byte range.
Figure 16. Data ROM Window Register
DWR
Data ROM Window Register
(C9h, Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
DWR0
DWR1
DWR2
DWR3
DWR4
DWR5
DWR6
DWR7
= Data
= Data
= Data
= Data
= Data
= Data
= Data
= Data
ROM Window 0
ROM Window 1
ROM Window 2
ROM Window 3
ROM Window 4
ROM Window 5
ROM Window 6
ROM Window 7
DWR7-DWR0. These are the Data Rom Window
bits that correspond to the upper bits of data ROM
program space. This register is undefined after reset.
Note. Care is required when handling the DRWR as
it is write only. For this reason, it is not allowed to
change the DRWR contents while executing interrupts drivers, as the driver cannot save and than restore its previous content. If it is impossible to avoid
the writing of this register in interrupts drivers, an image of this register must be saved in a RAM location,
and each time the program writes the DRWR it
writes also the image register. The image register
must be written first, so if an interrupt occurs between the two instructions the DRWR register is not
affected.
Figure 17. Data ROM Window Memory Addressing
DATA ROM
13
WINDOW REGISTER 7
CONTENTS
12
11
10
9
8
7
6
6
5
4
3
2
1
0
(DWR)
5
4
3
2
1
0 PROGRAM SPACE ADDRESS
READ
5
4
3
2
1
0
0
1
0
0
0
1
0
1
1
0
0
1
0
0
0
1
1
0
0
1
DATA SPACE ADDRESS
40h-7Fh
IN INSTRUCTION
Example:
DWR=28h
ROM
ADDRESS:A19h
0
0
0
0
1
1
0
0
1
1
0
0
DATA SPACE ADDRESS
59h
VR01573B
14/64

ST6391,92,93,95,97,99
MEMORY SPACES (Continued)
Data RAM/EEPROM/OSD RAM Addressing
In all members of the ST639x family 64 bytes of data
RAM are directly addressablein the data space from
80h to BFh addresses. The additional 192 bytes of
RAM, the 384 bytes of EEPROM , and the OSD
RAM can be addressed using the banks of 64
bytes located between addresses 00h and 3Fh.
The selection of the bank is done by programming
the Data RAM Bank Register (DRBR) located at
the E8h address of the Data Space. In this way
each bank of RAM, EEPROM or OSD RAM can select 64 bytes at a time. No more than one bank
should be set at a time.
Figure 18. Data RAM Bank Register
DRBR
Data RAM
Bank Register
(E8h, Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
DRBR0
DRBR1
DRBR2
DRBR3
DRBR4
DRBR5
DRBR6
DRBR7
DRBR7,DRBR1,DRBR0. These bits select the
EEPROM pages.
DRBR6, DRBR5. Each of these bits, when set, will
select one OSD RAM register page.
DRBR4,DRBR3,DRBR2. Each of these bits, when
set, will select one RAM page.
This register is undefined after reset.
Table 5 summarizes how to set the Data RAM
Bank Register in order to select the various banks
or pages.
Note :
Care is required when handling the DRBR as it is
write only. For this reason, it is not allowed to
change the DRBR contents while executing interrupts drivers, as the driver cannot save and than
restore its previous content. If it is impossible to
avoid the writing of this register in interrupts drivers, an image of this register must be saved in a
RAM location, and each time the program writes
the DRBR it writes also the image register.
The image register must be written first, so if an interrupt occurs between the two instructions the
DRBR is not affected.
Table 5. Data RAM Bank Register Set-up
DRBR Value
Selection
Hex.
Binary
01h
0000 0001
EEPROM Page 0
02h
0000 0010
EEPROM Page 1
03h
0000 0011
EEPROM Page 2
81h
1000 0001
EEPROM Page 3
82h
1000 0010
EEPROM Page 4
83h
1000 0011
EEPROM Page 5
04h
0000 0100
RAM Page 2
08h
0000 1000
RAM Page 3
10h
0001 0000
RAM Page 4
20h
0010 0000
OSD Page 5
40h
0100 0000
OSD Page 6
All devices
ST6395 and ST6397
ONLY
All devices
15/64

ST6391,92,93,95,97,99
MEMORY SPACES (Continued)
EEPROM Description
The data space of ST639x family from 00h to 3Fh
is paged as described in Table 5. 384 bytes of
EEPROM located in six pages of 64 bytes (pages
0,1,2,3,4 and 5, see Table 5).
Through the programming of the Data RAM Bank
Register (DRBR=E8h) the user can select the
bank or page leaving unaffected the way to address the static registers. The way to address the
“dynamic” page is to set the DRBR as described in
Table 5 (e.g. to select EEPROM page 0, the DRBR
has to be loaded with content 01h, see Data
RAM/EEPROM/OSD RAM addressing for additional information). Bits 0, 1 and 7 of the DRBR are
dedicated to the EEPROM.
The EEPROM pages do not require dedicated instructions to be accessed in reading or writing. The
EEPROM is controlled by the EEPROM Control
Register (EECR=EAh). Any EEPROM location can
be read just like any other data location, also in terms
of access time.
To write an EEPROM location takes an average
time of 5 ms (10ms max) and during this time the
EEPROM is not accessible by the Core. A busy
flag can be read by the Core to know the EEPROM
status before trying any access. In writing the
EEPROM can work in two modes: Byte Mode
(BMODE) and Parallel Mode (PMODE). The
BMODE is the normal way to use the EEPROM
and consists in accessing one byte at a time. The
PMODE consists in accessing 8 bytes per time.
Figure 19. EEPROM Control Register
EECR
EEPROM Control Register
(EAh, Read/Write)
D7 D6 D5 D4 D3 D2 D1 D0
EN = EEPROM Enable Bit
BS = EEPROM Busy Bit
PE = Parallel Mode Enable Bit
PS = Parallel Start Bit
Reserved (Must be set Low)
Reserved (Must be set Low)
SB = Stand-by Enable Bit
Unused
16/64

D7. Not used
SB. WRITE ONLY. If this bit is set the EEPROM is
disabled (any access will bemeaningless) and the
power consumption of the EEPROM is reduced to
the leakage values.
D5, D4. Reserved for testing purposes, they must
be set to zero.
PS. SET ONLY. Once in Parallel Mode, as soon as
the user software sets the PS bit the parallel writing
of the 8 adjacent registers will start. PS is internally
reset at the end of the programming procedure.
Note that less than 8 bytes can be written; after
parallel programming the remaining undefined
bytes will have no particular content.
PE. WRITE ONLY. This bit must be set by the
user program in order to perform parallel programming (more bytes per time). If PE is set and the
“parallel start bit” (PS) is low, up to 8 adjacent bytes
can be written at the maximum speed, the content
being stored in volatile registers. These 8 adjacent
bytes can be considered as row, whose A7, A6,
A5, A4, A3 are fixed while A2, A1 and A0 are the
changing bytes. PE is automatically reset at the
end of any parallel programming procedure. PE
can be reset by the user software before starting
the programming procedure, leaving unchanged
the EEPROM registers.
BS. READ ONLY. This bit will be automatically set
by the CORE when the user program modifies an
EEPROM register. The user program has to test it
before any read or write EEPROM operation; any
attempt to access the EEPROM while “busy bit” is
set will be aborted and the writing procedure in progress completed.
EN. WRITE ONLY. This bit MUST be set to one in
order to write any EEPROM register. If the user
program will attempt to write the EEPROM when
EN= “0” the involved registers will be unaffected
and the “busy bit” will not be set.
AfterRESET the contentof EECR register will be 00h.
Notes :
When the EEPROM is busy (BS=“1”) the EECR
can not be accessed in write mode, it is only possible to read BS status. This implies that as long as
the EEPROM is busy it is not possible to change
the status of the EEPROM control register. EECR
bits 4 and 5 are reserved for test purposes, and
must never be set to “1”.
ST6391,92,93,95,97,99
MEMORY SPACES (Continued)
Additional Notes on Parallel Mode. If the user
wants to perform a parallel programming the first
action should be the set to one the PE bit; from this
moment the first time the EEPROM will be addressed in writing, the ROW address will be
latched and it will be possible to change it only at
the end of the programming procedure or by resetting PE without programming the EEPROM. After
the ROW address latching the Core can “see” just
one EEPROM row (the selected one) and any attempt to write or read other rows will produce errors. Do not read the EEPROM while PE is set.
As soon as PE bit is set, the 8 volatile ROW latches
are cleared. From this moment the user can load
data in the whole ROW or just in a subset. PS setting will modify the EEPROM registers corresponding to the ROW latches accessed after PE. For
example, if the software sets PE and accesses
EEPROM in writing at addresses 18h,1Ah,1Bh and
then sets PS, thesethree registers will be modified at
the same time; the remaining bytes will have no particular content. Note that PE is internally reset at the
end of the programming procedure. This implies that
the user must set PE bit between two parallel programming procedures. Anyway the user can set and
then reset PE without performing any EEPROMprogramming. PS is a set only bit and is internally reset
at the end of the programming procedure. Note that
if the user tries to set PS while PE is not set there will
not be any programming procedure and the PS bit
will be unaffected. Consequently PS bit can not be
set if EN is low. PS can be affected by the user set if,
and only if, EN and PE bits are also set to one.
INTERRUPT
The ST639x Core can manage 4 different maskable interrupt sources, plus one non-maskable interrupt source (top priority level interrupt). Each
source is associated with a particular interrupt vector that contains a Jump instruction to the related
interrupt service routine. Each vector is located in
the Program Space at a particular address (see
Table 6). When a source provides an interrupt request, and the request processing is also enabled
by the ST639x Core, then the PC register is loaded
with the address of the interrupt vector (i.e. of the
Jump instruction). Finally, the PC is loaded with the
address of the Jump instruction and the interrupt
routine is processed.
The relationship between vector and source and
the associated priority is hardware fixed for the different ST639x devices. For some interrupt sources
it is also possible to select by software the kind of
event that will generate the interrupt.
All interrupts can be disabled by writing to the GEN
bit (global interrupt enable) of the interrupt option
register (address C8h). After a reset, ST639x is in
non maskable interrupt mode, so no interrupts will
be accepted and NMI flags will be used, until a
RETI instruction is executed. If an interrupt is executed, one special cycle is made by the core, during that the PC is set to the related interrupt vector
address. A jump instruction at this address has to
redirect program execution to the beginning of the
related interrupt routine. The interrupt detecting cycle, also resets the related interrupt flag (not available to the user), so that another interrupt can be
stored for this current vector, while its driver is under execution.
If additional interrupts arrive from the same source,
they will be lost. NMI can interrupt other interrupt
routines at any time, while other interrupts cannot
interrupt each other. If more than one interrupt is
waiting for service, they are executed according to
their priority. The lower the number, the higher the
priority. Priority is, therefore, fixed. Interrupts are
checked during the last cycle of an instruction
(RETI included). Level sensitive interrupts have to
be valid during this period.
17/64

ST6391,92,93,95,97,99
INTERRUPT (Continued)
Table 6. Interrupt Vectors/Sources
Relationships
Timer 2
Interrup t
Vector # 1
0FF6h-0FF7h
Vsync
Interrup t
Vector # 2
0FF4h-0FF5h
Interrupt Option Register
The Interrupt Option Register (IOR register, location C8h) is used to enable/disable the individual
interrupt sources and to select the operating mode
of the external interrupt inputs. This register can be
addressed in the Data Space as RAM location at
the C8h address, nevertheless it is write-only register that can not be accessed with single-bit operations. The operating modes of the external
interrupt inputs associated to interrupt vectors #1
and #2 are selected through bits 4 and 5 of the IOR
register.
Timer 1
Interrup t
Vector # 3
0FF2h-0FF3h
Figure 20. Interrupt Option Register
PC4/PWRIN
Interrup t
Vector # 4
0FF0h-0FF1h
Inte rrupt Source
PC6/IRIN
Pin
(1)
Associated
Vector
Interrup t
Vector # 0 (NMI)
Vector Address
0FFCh-0FFDh
IOR
Interr upt Option Register
(C8h, Write Only)
Note 1. This pin is associated with the NMI Interrupt Vector
Interrupt Vectors/Sources
The ST639x Core includes 5 different interrupt
vectors in order to branch to 5 different interrupt
routines. The interrupt vectors are located in the
fixed (or static) page of the Program Space.
The interrupt vector associated with the non-maskable interrupt source is named interrupt vector #0.
It is located at the (FFCh,FFDh) addresses in the
Program Space. This vector is associated with the
PC6/IRIN pin.
The interrupt vectors located at addresses
(FF6h,FF7h),
(FF4h,FF5h),
(FF2h,FF3h),
(FF0h,FF1h) are named interrupt vectors #1, #2,
#3 and #4 respectively. These vectors are associated with TIMER 2 (#1), VSYNC (#2), TIMER 1
(#3) and PC4(PWRIN) (#4).
Interrupt Priority
The non-maskable interrupt request has the highest priority and can interrupt any other interrupt
routines at any time, nevertheless the other interrupts cannot interrupt each other. If more than one
interrupt request is pending, they are processed by
the ST639x Core according to their priority level:
vector #1 has the higher priority while vector #4 the
lower. The priority of each interrupt source is hardware fixed.
18/64

D7 D6 D5 D4 D3 D2 D1 D0
Unuse d
GEN = Global Enab le Bit
ES2 = Edge Selection Bit
EL1 = Edge Level Selection Bit
Unuse d
D7. Not used.
EL1. This is the Edge/Level selection bit of interrupt #1. When set to one, the interrupt is generated
on low level of the related signal; when cleared to
zero, the interrupt is generated on falling edge. The
bit is cleared to zero after reset.
ES2. This is the edge selection bit on interrupt #2.
This bit is used on the ST639x devices with on-chip
OSD generator for VSYNC detection.
GEN. This is the global enable bit. When set to one all
interrupts are globally enabled;when this bit is cleared
to zero all interrupts are disabled (excluding NMI).
D3 - D0. These bits are not used.
ST6391,92,93,95,97,99
INTERRUPT (Continued)
Interrupt Procedure
The interrupt procedure is very similar to a call procedure; the user can consider the interrupt as an
asynchronous call procedure. As this is an asynchronous event the user does not know about the
context and the time at which it occurred. As a result the user should save all the data space registers which will be used inside the interrupt routines.
There are separate sets of processor flags for normal, interrupt and non-maskable interrupt modes
which are automatically switched and so these do
not need to be saved.
The following list summarizes the interrupt procedure (refer also to Figure 21. Interrupt Processing
Flow Chart):
- Interrupt detection
flags C and Z of the main routine are ex- The
changed with the flags C and Z of the interrupt
routine (resp. the NMI flags)
value of the PC is stored in the first level of
- The
the stack - The normal interrupt lines are inhibited (NMI still active)
- The edge flip-flop is reset
- The related interrupt vector is loaded in the PC.
selected registers are saved inside the in- User
terrupt service routine (normally on a software
stack)
- The source of the interrupt is found by polling
(if more than one source is associated to the
same vector)
- Interrupt servicing
- Return from interrupt (RETI)
the ST639x core switches back
- Automatically
to the normal flags (resp the interrupt flags)
and pops the previous PC value from the stack
The interrupt routine begins usually by the identification of the device that has generated the interrupt request. The user should save the registers
which are used inside the interrupt routine (that
holds relevant data) into a software stack.
After the RETI instruction execution, the Core carries out the previous actions and the main routine
can continue.
Figure 21. Interrupt Processing Flow-Chart
INSTRUCTION
FE TCH
INST RUCTION
EX ECUTE
INST RUCTION
WA S
THE INST RUCTION
A RETI
NO
LOAD PC FROM
INTERRUPT VECTOR
( FF C / FFD )
YE S
YES
IS THE CORE
ALREADY IN
NORMAL MODE ?
?
SET
INTE RRUPT MAS K
NO
CLEA R
INTERRUPT MAS K
PUSH THE
PC INTO THE STAC K
SELECT
PROGRAM FLA GS
SEL ECT
INTERNAL MODE FLAG
” POP ”
THE STACK ED PC
NO
CHECK IF THERE IS
AN INTERRUPT REQUES T
AND INTE RRUPT MASK
?
YES
VA000014
ST639x Interrupt Details
IR Interrupt (#0). The IRIN/PC6 Interrupt is connected to the first interrupt #0 (NMI, 0FFCh). If the
IRINT interrupt is disabled at the Latch circuitry,
then it will be high. The #0 interrupt input detects a
high to low level. Note that once #0 has been
latched, then the only way to remove the latched
#0 signal is to service the interrupt. #0 can interrupt
the other interrupts. A simple latch is provided from
the PC6(IRIN) pin in order to generate the IRINT
signal. This latch can be triggered by either the
positive or negative edge of IRIN signal. IRINT is
inverted with respect to the latch. The latch can be
read by software and reset by software.
19/64

ST6391,92,93,95,97,99
INTERRUPT (Continued)
TIMER 2 Interrupt (#1). The TIMER 2 Interrupt is
connectedto the interrupt #1 (0FF6h). The TIMER 2
interrupt generatesa low level (which is latchedin the
timer). Only the low level selection for #1 can be used.
Bit 6 of the interrupt option register C8h has to be set.
VSYNC Interrupt (#2). The VSYNC Interrupt is
connected to the interrupt #2. When disabled the
VSYNC INT signal is low. The VSYNC INT signal is
inverted with respect to the signal applied to the
VSYNC pin. Bit 5 of the interrupt option register
C8h is used to select the negative edge (ES2=0) or
the positive edge (ES2=1); the edge will depend
on the application. Note that once an edge has
been latched, then the only way to remove the
latched signal is to service the interrupt. Care must
be taken not to generate spurious interrupts. This
interrupt may be used for synchronize to the
VSYNC signal in order to change characters in the
OSD only when the screen is on vertical blanking
(if desired). This method may also be used to blink
characters.
TIMER 1 Interrupt (#3). The TIMER 1 Interrupt is
connected to the fourth interrupt #3 (0FF2h) which
detects a low level (latched in the timer).
20/64

PWR Interrupt (#4). The PWR Interrupt is connected to the fifth interrupt #4 (0FF0h). If the
PWRINT is disabled at the PWR circuitry, then it
will be high. The #4 interrupt input detects a low
level. A simple latch is provided from the PC4
(PWRIN)pin in order to generate the PWRINT signal. This latch can be triggered by either the positive or negative edge of the PWRIN signal.
PWRINT is inverted with respect to the latch. The
latch can be reset by software.
Notes Global disable does not reset edge sensitive interrupt flags. These edge sensitive interrupts
become pending again when global disabling is released. Moreover, edge sensitive interrupts are
stored in the related flags also when interrupts are
globally disabled, unless each edge sensitive interrupt is also individually disabled before the interrupting event happens. Global disable is done by
clearing the GEN bit of Interrupt option register,
while any individual disable is done in the control
register of the peripheral. The on-chip Timer peripherals have an interrupt requestflag bit (TMZ), this
bit is set to one when the device wants to generate an
interrupt request and a mask bit (ETI) that must be set
to one to allow the transfer of the flag bit to the Core.
ST6391,92,93,95,97,99
RESET
The ST639x devices can be reset in two ways: by the
external reset input (RESET) tied low and by the
hardware activated digital watchdog peripheral.
RESET Input
The external active low reset pin is used to reset the
ST638x devices and provide an orderly software
startup procedure. The activation of the Reset pin
may occur at any time in the RUN or WAIT mode.
Even short pulses at the reset pin will be accepted
since the reset signal is latched internally and is only
cleared after 2048 clocks at the oscillator pin. The
clocks from the oscillator pin to the reset circuitry are
buffered by a schmitt trigger so that an oscillator in
start-up conditions will not give spurious clocks.
When the reset pin is held low, the external crystal oscillator is also disabled in order to reduce current consumption. The MCU is configured in the Reset mode
as long as the signal of the RESET pin is low. The
processingof theprogramis stoppedandthe standard
Input/Outputports (port A, port B and port C) are in the
input state. As soon as the level on the reset pin becomes high, the initialization sequence is executed.
Refer to the MCU initialization sequencefor additional
information.
Watchdog Reset
The ST639x devices are provided with an on-chip
hardware activated digital watchdog function in order to provide a graceful recovery from a software
upset. If the watchdog register is not refreshed and
the end-of-count is reached, then the reset state
will be latched into the MCU and an internal circuit
pulls down the reset pin. This also resets the
watchdog which subsequently turns off the pulldown and activates the pull-up device at the reset
pin. This causes the positive transition at the reset
pin. The MCU will then exit the reset state after
2048 clocks on the oscillator pin.
Application Notes
An external resistor between VDD and the reset pin
is not required because an internal pull-up device
is provided. The user may prefer to add an external
pull-up resistor.
An internal Power-on device does not guarantee
that the MCU will exit the reset state when VDD is
above 4.5V and therefore the RESET pin should
be externally controlled.
Figure 22. Internal Reset Circuit
ST6
INTERNAL RESET
OSCILLATOR
SIGNAL
COUNTER
TO ST6
1.0k
RESET
(ACTIVE LOW)
RESET
VDD
300k
WATCHDOG RESET
VA000200
21/64

ST6391,92,93,95,97,99
RESET (Continued)
Figure 23. Reset & Interrupt Processing
Flow-Chart
Figure 24. Restart Initialization Program
Flow-Chart
RESET
RESET
JP
JP: 2 BYTES/4 CYCLES
RESET VECTOR
NMI MASK SET
INT LATCH CLEARED
( IF PRESENT )
INITIALIZATION
ROUTINE
RETI
SELECT
NMI MODE FLAGS
PUT FFEh
ON ADDRESS BUS
YES
RETI: 1BYTES/2 CYCLES
VA 000181
MCU Initialization Sequence
When a reset occurs the stack is reset to program
counter, the PC is loaded with the address of the
reset vector (located in the program ROM at addresses FFEh & FFFh). A jump instruction to the
beginning of the program has to be written into
these locations. After a reset the interrupt mask is
automatically activated so that the Core is in nonmaskable interrupt mode to prevent false or ghost
interrupts during the restart phase. Therefore the
restart routine should be terminated by a RETI instruction to switch to normal mode and enable interrupts. If no pending interrupt is present at the
end of the reset routine, the ST639x will continue
with the instruction after the RETI; otherwise the
pending interrupt will be serviced.
RESET Low Power Mode
(ST6392 and ST6399 only)
When the reset pin is low, the quartz oscillator is
Disabled allowing reduced current consumption.
When the reset pin is raised the quartz oscillator is
enabled and oscillations will start to build up.The
internal reset circuitry will count 2048 clocks on the
oscillator pin before allowing the MCU to go out of
the reset state; the clocks are after a schmitt trigger
so that false or multiple counts are not possible.
IS RESET
STILL PRESENT ?
NO
LOAD PC
FROM RESET LOCATIONS
FFE / FFF
FETCH INSTRUCTION
VA000427
22/64

ST6391,92,93,95,97,99
WAIT & STOP MODES
The STOP and WAIT modes have been implemented in the ST639x Core in order to reduce the
consumption of the device when the latter has no
instruction to execute. These two modes are described in the following paragraphs. On ST639x as
the hardware activated digital watchdog function is
present the STOP instruction is de-activated and
any attempt to execute it will cause the automatic
execution of a WAIT instruction.
WAIT Mode
The configuration of the MCU in the WAIT mode occurs as soon as the WAIT instruction is executed.
The microcontroller can also be considered as being
in a “software frozen” state where the Core stops
processing the instructions of the routine, the contents of the RAM locations and peripheral registers
are saved as long as the power supply voltage is
higher than the RAM retention voltage but where the
peripheralsare still working.
The WAIT mode is used when the user wants to reduce the consumption of the MCU when it is in idle,
while not losing count of time or monitoring of external events. The oscillator is not stopped in order to
provide clock signal to the peripherals. The timers
counting may be enabled (writing the PSI bit in
TSCR register) and the timer interrupt may be also
enabled before entering the WAIT mode; this allows
the WAIT mode to be left when timer interrupt occurs. If the exit from the WAIT mode is performed
with a general RESET (either from the activation of
the external pin or by watchdog reset) the MCU will
enter a normal reset procedure as described in the
RESET chapter. If an interrupt is generated during
WAIT mode the MCU behaviour depends on the
state of the ST639x Core before the initialization of
the WAIT sequence, but also of the kind of the interrupt request that is generated. This case will be
described in the following paragraphs.In any case,
the ST639x Core does not generate any delay after the occurrence of the interrupt because the oscillator clock is still available.
STOP Mode
On ST639x the hardware watchdog is present and
the STOP instruction has been de-activated. Any
attempt to execute a STOP will cause the automatic execution of a WAIT instruction.
Exit from WAIT Mode
The following paragraphs describe the output procedure of the ST639x Core from WAIT mode when
an interrupt occurs. It must be noted that the restart
sequence depends on the original state of the
MCU (normal, interrupt or non-maskable interrupt
mode) before the start of the WAIT sequence, but
also of the type of the interrupt request that is generated. In all cases the GEN bit of IOR has to be set
to 1 in order to restart from WAIT mode. Contrary
to the operation of NMI in the RUN mode, the NMI
is masked in WAIT mode if GEN=0.
Normal Mode. If the ST639x Core was in the main
routinewhen the WAIT instruction has been executed,
theST6398xCore outputsfromthewait mode as soon
as any interrupt occurs; the related interrupt routine is
executedand at the end of the interruptservice routine
the instruction that follows the WAIT instruction is executedif no other interrupts are pending.
Non-maskable Interrupt Mode. If the WAIT instruction has been executed during the execution
of the non-maskable interrupt routine, the ST639x
Core outputs from the wait mode as soon as any
interrupt occurs: the instruction that follows the
WAIT instruction is executed and the ST639x Core
is still in the non-maskable interrupt mode even if
another interrupt has been generated.
Normal Interrupt Mode. If the ST639x Core was
in the interrupt mode before the initialization of the
WAIT sequence, it outputs from the wait mode as
soon as any interrupt occurs. Nevertheless, two
cases have to be considered:
– If the interrupt is a normal interrupt, the interrupt routine in which the WAIT was entered will
be completed with the execution of the instruction that follows the WAIT and the ST639x
Core is still in the interrupt mode. At the end of
this routine pending interrupts will be serviced
in accordance to their priority.
– If the interrupt is a non-maskable interrupt, the
non-maskable routine is processed at first.
Then, the routine in which the WAIT was entered will be completed with the execution of
the instruction that follows the WAIT and the
ST639x Core is still in the normal interrupt
mode.
Notes :
If all the interrupt sources are disabled, the restart
of the MCU can only be done by a Reset activation.
The Wait instruction is not executed if an enabled
interrupt request is pending. In the ST639x the
hardware activated digital watchdog function is
present. As the watchdog is always activated the
STOP instruction is de-activated and any attempt
to execute the STOP instruction will cause an execution of a WAIT instruction.
23/64

ST6391,92,93,95,97,99
ON-CHIP CLOCK OSCILLATOR
The internal oscillator circuit is designed to require
a minimum of external components. A crystal
quartz, a ceramic resonator, or an external signal
(provided to the OSCin pin) may be used to generate a system clock with various stability/cost tradeoffs. The typical clock frequency is 8MHz. Please
note that different frequencies will affect the operation
of those peripherals (D/As, SPI) whose reference frequencies are derived from the system clock.
The different clock generator options connection
methods are shown in Figures 25 and 26. One machine cycle takes 13 oscillator pulses; 12 clock
pulses are needed to increment the PC while and
additional 13th pulse is needed to stabilize the internal latches during memory addressing. This means
that with a clock frequency of 8MHz the machine cycle is 1.625µs.
The crystal oscillator start-up time is a function of
many variables: crystal parameters (especially RS),
oscillator load capacitance (CL), IC parameters, ambient temperature, and supply voltage.It must be observed that the crystal or ceramic leads and circuit
connections must be as short as possible. Typical
values for CL1 and CL2 are in the range of 15pF to
22pF but these should be chosen based on the crystal manufacturers specification. Typical input capacitance for OSCin and OSCout pins is 5pF.
The oscillator output frequency is internallydivided
by 13 to produce the machine cycle and by 12 to
produce the Timer and the Watchdog clock. A byte
cycle is the smallest unit needed to execute any
operation (i.e., increment the program counter). An
instruction may need two, four, or five byte cycles
to be executed (See Table 7).
Table 7. Intructions Timing with 8MHz Clock
Cycles
Execution
Time
Branch if set/reset
5 Cycles
8.125µs
Branch & Subroutine Branch
4 Cycles
6.50µs
Bit Manipulation
4 Cycles
6.50µs
Load Instruction
4 Cycles
6.50µs
Arithmetic & Logic
4 Cycles
6.50µs
Conditional Branch
2 Cycles
3.25µs
Program Control
2 Cycles
3.25µs
Instruc tion Type
24/64

Figure 25. Clock Generator Option (1)
Figure 26. Clock Generator Option (2)
Figure 27. OSCin, OSCout Diagram
ST6391,92,93,95,97,99
INPUT/OUTPUT PORTS
The ST639x microcontrollers use three standard
I/O ports (A,B,C) with up to eight pins on each port;
refer to the device pin configurations to see which
pins are available.
Each line can be individually programmed either in
the input mode or the output mode as follows by
software.
- Output
- Input with on-chip pull-up resistor (selected by
software)
- Input without on-chip pull-up resistor (selected
by software)
Note: pins with 12V open-drain capability do not
have pull-up resistors.
In output mode the following hardware configurations are available:
- Open-drain output 12V (PA4-PA7, PC4-PC7)
- Open-drain output 5V (PC0-PC3)
- Push-pull output (PA0-PA3, PB0-PB6)
The lines are organized in three ports (port A,B,C).
The ports occupy 6 registers in the data space.
Each bit of these registers is associated with a particular line (for instance, the bits 0 of the Port A
Data and Direction registers are associated with
the PA0 line of Port A).
There are three Data registers (DRA, DRB, DRC),
that are used to read the voltage level values of the
lines programmed in the input mode, or to write the
logic value of the signal to be output on the lines
configured in the output mode. The port Data Registers can be read to get the effective logic levels of
the pins, but they can be also written by the user
software, in conjunction with the related Data Direction Register, to select the different input mode
options. Single-bit operations on I/O registers (bit
set/reset instructions) are possible but care is necessary because reading in input mode is made
from I/O pins and therefore might be influenced by
the external load, while writing will directly affect
the Port data register causing an undesired
changes of the input configuration. The three Data
Direction registers (DDRA, DDRB, DDRC) allow
the selection of the direction of each pin (input or
output).
All the I/O registers can be read or written as any
other RAM location of the data space, so no extra
RAM cell is needed for port data storing and manipulation. During the initialization of the MCU, all
the I/O registers are cleared and the input mode
with pull-up is selected on all the pins thusavoiding
pin conflicts(with the exception of PC2 that is set in
output mode and is set high ie. high impedance).
Details of I/O Ports
When programmed as an input a pull-up resistor (if
available) can be switched active under program
control. When programmed as an output the I/O
port will operate either in the push-pull mode or the
open-drain mode according to the hardware fixed
configuration as specified below.
Port A. PA0-PA3 are available as push-pull when
outputs. PA4-PA7 are available as open-drain (no
push-pull programmability) capable of withstanding 12V (no resistive pull-up in input mode). PA6PA7 has been specially designed for higher driving
capability and are able to sink 25mA with a maximum VOL of 1V.
Port B. All lines are configured as push-pull when
outputs.
Port C. PC0-PC3 are available as open-drain capable of withstanding a maximum VDD+0.3V. PC4PC7 are available as open-drain capable of
withstanding 12V (no resistive pull-up in input
mode). Some lines are also used as I/O buffers for
signals coming from the on-chip SPI.
In this case the final signal on the output pin is
equivalent to a wired AND with the programmed
data output.
If the user needs to use the serial peripheral, the
I/O line should be set in output mode while the
open-drain configuration is hardware fixed; the
corresponding data bit must set to one. If the
latched interrupt functions are used (IRIN, PWRIN)
then the corresponding pins should be set to input
mode.
On ST639x the I/O pins with double or special
functions are:
- PC0/SCL (connected to the SPI clock signal)
- PC1/SDA (connected to the SPI data signal)
- PC3/SEN (connected to the SPI enable signal)
- PC4/PWRIN (connected to the PWRIN interrupt latch)
- PC6/IRIN (connected to the IRIN interrupt
latch)
All the Port A,B and C I/O lines have Schmitt-trigger input configuration with a typical hysteresis of
1V.
25/64

ST6391,92,93,95,97,99
INPUT/OUTPUT PORTS (Continued)
Table 8. I/O Port Options Selection
DDR
DR
Mode
Option
0
0
Input
With on-chip pull-up
resistor
0
1
Input
Without on-chip pull-up resistor
1
X
Output
Open-drain or Push-Pull
I/O Pin Programming
Each pin can be individually programmed as input or
output with different input and output configurations.
This is achieved by writing to the relevant bit in the
data (DR) and data direction register (DDR). Table
8 shows all the port configurations that can be selected by the user software.
Figure 29. Port A, B, C Data Register
Note: X: Means don’t care.
Figure 28. Port A, B, C Data Register
DDRA, DDRB,DDRC
DRA, DRB, DRC
Port A, B, C Data Direction Register
( C4h PA, C5h PB, C6h PC Read/ Write )
Port A, B, C Data Register
( C0h PA, C1h PB, C2h PC Read/ Write )
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
PA0 - PA7 = Data Direction Bits
PB0 - PB7 = Data Direction Bits
PC0 - PC7 = Data Direction Bits
“0” Defines bit as Inpu t
”1” Defines bit as Outpu t
A0 - PA7 = Data Bits
PB0 - PB7 = Data Bits
PC0 - PC7 = Data Bits
PA7-PA0. These are the I/O port A data bits. Reset
at power-on.
PB7-PB0.These are the I/O port B data bits. Reset
at power-on.
PC7-PC0. Set to 04h at power-on. Bit 2 (PC2 pin)
is set to one (open drain therefore high impedence).
26/64

PA7-PA0. These are the I/O port A data direction
bits. When a bit is cleared to zero the related I/O
line is in input mode, if bit is set to one the related
I/O line is in output mode. Reset at power-on.
PB7-PB0. These are the I/O port B data direction
bits. When a bit is cleared to zero the related I/O
line is in input mode, if bit is set to one the related
I/O line is in output mode. Reset at power-on.
PC7-PC0. These are the I/O port C data direction
bits. When a bit is cleared to zero the related I/O
line is in input mode, if bit is set to one the related
I/O line is in output mode. Set to 04h at power-on.
Bit 2 (PC2 pin) is set to one (output mode selected).
ST6391,92,93,95,97,99
INPUT/OUTPUT PORTS (Continued)
Input/Output Configurations
The following schematics show the I/O lines hardware configuration for the different options. Figure
30 shows the I/O configuration for an I/O pin with
open-drain 12V capability (standard drive and high
drive). Figure 31 shows the I/O configuration for an
I/O pin with push-pull and with open drain 5V capability.
Figure 30. I/O Configuration Diagram
(Open Drain 12V)
Notes :
The WAIT instruction allows the ST639x to be
used in situations where low power consumption is
needed. This can only be achieved however if the
I/O pins either are programmed as inputs with well
defined logic levels or have no power consuming
resistive loads in output mode. As the same die is
used for the different ST639x versions the unavailable I/O lines of ST639x should be programmed in
output mode.
Single-bit operations on I/O registers are possible
but care is necessary because reading in input
mode is made from I/O pins while writing will directly affect the Port data register causing an undesired changes of the input configuration.
Figure 31. I/O Configuration Diagram (Open Drain 5V, Push-pull)
27/64

ST6391,92,93,95,97,99
TIMERS
The ST639x devices offer two on-chip Timer peripherals consisting of an 8-bit counter with a 7-bit programmable prescaler, thus giving a maximum count
of 215, and a control logic that allows configuring the
peripheral operating mode. Figure 32 shows the
timer block diagram. The content of the 8-bit counters can be read/written in the Timer/Counter registers TCR that can be addressed in the data space as
RAM location at addresses D3h (Timer 1) and DBh
(Timer 2). The state of the 7-bit prescaler can be
read in the PSC register at addresses D2h (Timer 1)
and DAh (Timer 2). The control logic is managed by
TSCR registers at D4h (Timer 1) and DCh (Timer 2)
addresses as described in the following paragraphs.
The following description applies to both Timer 1
and Timer 2. The 8-bit counter is decrement by the
output (rising edge) coming from the 7-bit prescaler and can be loaded and read under program
control. When it decrements to zero then the TMZ
(timer zero) bit in the TSCR is set to one. If the ETI
(enable timer interrupt) bit in the TSCR is also set
to one an interrupt request, associated to interrupt
vector #3 (for Timer 1) and #1 for Timer 2, is generated. The interrupt of the timer can be used to exit
the MCU from the WAIT mode.
Figure 32. Timer Peripheral Block Diagram
28/64

The prescaler decrements on rising edge. The
prescaler input is the oscillator frequency divided
by 12.
Depending on the division factor programmed by
PS2/PS1/PS0 (see Table 9) bits in the TSCR, the
clock input of the timer/counter register is multiplexed to different sources.
On division factor 1, the clock input of the prescaler is
also that of timer/counter; on factor2, bit 0 of prescaler
register is connectedto the clock input of TCR.
This bit changes its state with the half frequency of
prescaler clock input. On factor 4, bit 1 of PSC is
connected to clock input of TCR, and so on. On division factor 128, the MSB bit 6 of PSC is connected to clock input of TCR. The prescaler
initialize bit (PSI) in the TSCR register must be set
to one to allow the prescaler (and hence the
counter) to start. If it is cleared to zero then all of
the prescaler bits are set to one and the counter is
inhibited from counting.
The prescaler can be given any value between 0
and 7Fh by writing to the related register address,
if bit PSI in the TSCR register is set to one. The tap
of the prescaler is selected using the PS2/PS1/PS0
bits in the control register. Figure 33 shows the
timer working principle.
ST6391,92,93,95,97,99
TIMERS (Continued)
Figure 33. Timer Working Principle
Timer Operating Modes
As on ST639x devices the external TIMER pin is not
available the only allowed operating mode is the output mode that have to be selected by setting to 1 bit
4 and by clearing to 0 bit 5 in the TSCR1 register.
This procedurewill enable both Timer 1 and Timer 2.
Output Mode (TSCR1 D4 = 1, TSCR1 D5 = 0). On
this mode the timer prescaler is clocked by the
prescaler clock input (OSC/12). The user can select the desired prescaler division ratio through the
PS2/PS1/PS0 bits. When TCR count reaches 0, it
sets the TMZ bit in the TSCR.
The TMZ bit can be tested under program control
to perform timer functions whenever it goes high.
Bit D4 and D5 on TSCR2 (Timer 2) register are not
implemented.
Timer Interrupt
When the counter register decrements to zero and
the software controlled ETI (enable timer interrupt)
bit is set to one then an interrupt request associated to interrupt vector #3 (for Timer 1) and to interrupt vector #1 (for Timer 2) is generated. When the
counter decrements to zero also the TMZ bit in the
TSCR register is set to one.
Notes :
TMZ is set when the counter reaches 00H ; however, it may be set by writing 00H in the TCR register or setting the bit 7 of the TSCR register. TMZ
bit must be cleared by user software when servicing the timer interrupt to avoid undesired interrupts
when leaving the interrupt service routine. After reset, the 8-bit counter register is loaded to FFh while
the 7-bit prescaler is loaded to 7Fh , and the TSCR
register is cleared which means that timer is
stopped (PSI=0) and timer interrupt disabled.
A write to the TCR register will predominate over
the 8-bit counter decrement to 00h function, i.e. if a
write and a TCR register decrement to 00h occur
simultaneously, the write will take precedence, and
the TMZ bit is not set until the 8-bit counter reaches
00h again. The values of the TCR and the PSC
registers can be read accurately at any time.
29/64

ST6391,92,93,95,97,99
TIMERS (Continued)
Figure 34. Timer Status Control Registers
The TSCR1 and TSCR2 registers are cleared on
reset. The correct D4-D5 combination must be
written in TSCR1 by user’s software to enable the
operation of Timer 1 and Timer 2.
TSCR
Imer 1&2 Status Control Registers
DAh Timer 1, DCh Timer 2,
Read/ Write
Table 9. Prescaler Division Factors
D7 D6 D5 D4 D3 D2 D1 D0
PS0 = Prescaler Mux. Select
PS1 = Prescaler Mux. Select
PS2 = Prescaler Mux. Select
PSI = Prescaler Initialize Bit
*
D4 = Timers Enable Bit
D5 = Timers Enable Bit*
ETI = Enable Timer Inte rrupt
TMZ = Timer Zero Bit
*
Only Available in TSCR1
TMZ. Low-to-high transition indicates that the timer
count register has decrement to zero. This bit must
be cleared by user software before to start with a
new count.
ETI. This bit, when set, enables the timer interrupt
(vector #3 for Timer 1, vector #1 for Timer 2) request.
If ETI=0 the timer interrupt is disabled. If ETI= 1 and
TMZ= 1 an interrupt request is generated.
D5. This is the timers enable bit D5. It must be
cleared to 0 together with a set to 1 of bit D4 to enable both Timer 1 and Timer 2 functions. It is not
implemented on TSCR2 register.
D4. This is the timers enable bit D4. This bit must
be set to 1 together with a clear to 0 of bit D5 to enable both Timer 1 and Timer 2 functions. It is not
implemented on TSCR2 register.
D5
D4
Timers
0
0
Disabled
0
1
Enabled
1
X
Reserved
PS2
PS1
PS0
Divided 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
Figure 35. Timer Counter Registers
TCR
Timer Counter 1&2 Register
D3h Timer 1, DBh Timer 2, Read/ Write
D7 D6 D5 D4 D3 D2 D1 D0
D7 - D0 = Counter bits
Figure 36. Timer Counter Registers
PSC
PS1. Used to initialize the prescaler and inhibit its
countingwhile PSI = 0 the prescaler is set to 7Fh and
the counter is inhibited. When PSI = 1 the prescaler
is enabled to count downwards. As long as PSI= 0
both counter and prescaler are not running.
PS2-PS0. These bits select the division ratio of the
prescaler register. (see Table 9)
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
TimerPrescaler 1&2 Register
D2h Timer 1, DAh Timer 2, Read/ Write
D7 D6 D5 D4 D3 D2 D1 D0
D6 - D0 = Prescaler bits
Always read as “0”
ST6391,92,93,95,97,99
HARDWARE ACTIVATED DIGITAL WATCHDOG FUNCTION
The hardware activated digital watchdogfunction consists of a down counter that is automatically initialized
after reset so that this function does not need to be activated by the user program. As the watchdogfunction
is always activated this down counter can not be used
as a timer. The watchdogis using onedata space register (HWDR location D8h). The watchdog register is
set to FEh on reset and immediately starts to count
down, requiring no software start. Similarly the hardware activated watchdog can not be stopped or delayed by software.
The watchdog time can be programmed using the 6
MSbits in the watchdog register, this gives the possibility to generate a reset in a time between 3072 to
196608oscillator cycles in 64 possible steps. (With a
clock frequency of 8MHz this means from 384µs to
24.576ms). The reset is prevented if the register is
reloaded with the desired value before bits 2-7 decrement from all zeros to all ones.
The presence of the hardware watchdog deactivates
the STOP instruction and a WAIT instruction is automatically executed instead of a STOP. Bit 1 of the
watchdog register (set to one at reset) can be used to
generatea software reset if cleared to zero). Figure 37
shows the watchdog block diagram while Figure 38
shows its working principle.
Figure 38. Hardware Activated Watchdog
Working Principle
Figure 37. Hardware Activated Watchdog Block Diagram
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HARDWARE ACTIVATED DIGITAL WATCHDOG
FUNCTION (Continued)
Figure 39. Watchdog Register
HWDR
Hardware Activated Watchdog Register
(D8h, Read/ Write)
D7 D6 D5 D4 D3 D2 D1 D0
C = Watchdog Activation Bit
SR = Software Reset Bit
T1-T6 = Counter Bits
T1-T6. These are the watchdog counter bits. It
should be noted that D7 (T1) is the LSB of the
counter and D2 (T6) is the MSB of the counter,
these bits are in the opposite order to normal.
SR. This bit is set to one during the reset phase
and will generate a software reset if cleared to
zero.
C. This is the watchdog activation bit that is hardware set. The watchdog function is always activated independently of changes of value of this bit.
The register reset value is FEh (Bit 1-7 set to one,
Bit 0 cleared).
SERIAL PERIPHERAL INTERFACE
The ST639x Serial Peripheral Interface (SPI) has
been designed to be cost effective and flexible in
interfacing the various peripherals in TV applications.
It maintains the software flexibility but adds hardware configurations suitable to drive devices which
require a fast exchange of data. The three pins
dedicated for serial data transfer (single master
only) can operate in the following ways:
- as standard I/O lines (software configuration)
- as S-BUS or as I2CBUS (two pins)
- as standard (shift register) SPI
When using the hardware SPI, a fixed clock rate of
62.5kHz is provided.
It has to be noted that the first bit that is output on
the data line by the 8-bit shift register is the MSB.
SPI Data/Control Registers
For I/O details on SCL (Serial Clock), SDA (Serial
Data) and SEN (Serial Enable) please refer to I/O
Ports description with reference to the following
registers:
Port C data register, Address C2h (Read/Write).
- BIT D0 “SCL”
- BIT D1 “SDA”
- BIT D3 “SEN”
Port C data direction register, Address C6h
(Read/Write).
Figure 40. SPI Serial Data Register
SSDR
SPI Serial Data Register
(CCh, Read/ Write)
D7 D6 D5 D4 D3 D2 D1 D0
D0-D7 = Data Bits
D7-D0. These are the SPI data bits. They can be
neither read nor written when SPI is operating
(BUSY bit set). They are undefined after reset.
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ST6391,92,93,95,97,99
SERIAL PERIPHERAL INTERFACE (Continued)
Figure 42. SPI Control Register2
Figure 41. SPI Control Register 1
SCR1
SCR2
SPI Control Register 1
(EBh, Write only)
SPI Control Register 2
(ECh, Read/ Write)
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
2
BSY = Busy Bit 0
ACN = Acknowledge Bit
VRY/S = Verify/Sync.Enab le
TX/RX = Enable Bit
Unuse d
S-BUS/I C BUS Selection
STD/SPI Enable
STP = Stop Bit
STR = Start Bit
Unused
D7-D4. These bits are not used.
STR. This is Start bit for I2CBUS/S-BUS. This bit is
meaningless when STD/SPI enable bit is cleared to
zero. If this bit is set to one STD/SPI bit is also set to
“1” and SPI Start generation, before beginning of
transmission, is enabled. Set to zero after reset.
STP. This is Stop bit for I2CBUS/S-BUS. This bit is
meaningless when STD/SPI enable bit is cleared
to zero. If this bit is set to one STD/SPI bit is also
set to “1” and SPI Stop condition generation is enabled. STP bit must be reset when standard protocol is used (this is also the default reset
conditions). Set to zero after reset.
STD, SPI Enable. This bit, in conjunction with SBUS/I2CBUS bit, allows the SPI disable and will
select between I2CBUS/S-BUS and Standard
shift register protocols. If this bit is set to one, it
selects both I2CBUS and S-BUS protocols; final
selection between them is made by SBUS/I2CBUS bit. If this bit is cleared to zero when
S-BUS/I2CBUS is set to “1” the Standard shift
register protocol is selected. If this bit is cleared
to “0” when S-BUS/I2CBUS is cleared to 0 the SPI
is disabled. Set to zero after reset.
S-BUS/I2CBUS Selection. This bit, in conjunction
with STD/SPI bit, allows the SPI disable and will
select between I2CBUS and S-BUS protocols. If
this bit is cleared to “0” when STD bit is also “0”, the
SPI interface is disabled. If this bit is cleared to zero
when STD bit is set to “1”, the I2CBUS protocol will
be selected. If this bit is set to “1” when STD bit is
set to “1”, the S-BUS protocol will be selected.
Cleared to zero after reset.
Table 10. SPI Modes Selection
D1
STD/SP
D0
2
S-BUS/I C BUS
0
0
Disabled
0
1
STD Shift Reg.
1
0
I2C BUS
1
1
S-BUS
SPI Function
D7-D4. These bits are not used.
TX/RX.Write Only. When this bit is set, current byte
operation is a transmission. When it is reset, current operation is a reception. Set to zero after reset.
VRY/S.Read Only/Write Only. This bit has two different functions in relation to read or write operation. Reading Operation: when STD and/or TRX
bits is cleared to 0, this bit is meaningless. When
bits STD and TX are set to 1, this bit is set each
time BSY bit is set. This bit is reset during byte operation if real data on SDA line are different from
the output from the shift register. Set to zero after
reset. Writing Operation : it enables (if set to one)
or disables (if cleared to zero) the interrupt coming
from VSYNC pin. Undefined after reset. Refer to
OSD description for additional information.
ACN.Read Only. If STD bit (D1 of SCR1 register) is
cleared to zero this bit is meaningless. When STD
is set to one, this bit is set to one if no Acknowledge
has been received. In this case it is automatically
reset when BSY is set again. Set to zero after reset.
BSY.Read/Set Only. This is the busy bit. When a
one is loaded into this bit the SPI interface start the
transmission of the data byte loaded into SSDR
data register or receiving and building the receive
data into the SSDR data register. This is done in
accordance with the protocol, direction and
start/stop condition(s). This bit is automatically
cleared at the end of the current byte operation.
Cleared to zero after reset.
Note :
The SPI shift register is also the data transmission
register and the data received register; this feature
is made possible by using the serial structure of the
ST639x and thus reducing size and complexity.
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ST6391,92,93,95,97,99
SERIAL PERIPHERAL INTERFACE (Continued)
During transmission or reception of data, all access to serial data register is therefore disabled.
The reception or transmission of data is started by
setting the BUSY bit to “1”; this will be automatically reset at the end of the operation. After reset,
the busy bit is cleared to “0”, and the hardware SPI
disabled by clearing bit 0 and bit 1 of SPI control
register 1 to “0”. The outputs from the hardware
SPI are “ANDed” to the standard I/O software controlled outputs. If the hardware SPI is in operation
the Port C pins related to the SPI should be configured as outputs using the Data Direction Register
and should be set high. When the SPI is configured
as the S-BUS, the three pins PC0, PC1 and PC3
become the pins SCL, SDA and SEN respectively.
When configured as the I2CBUS the pins PC0 and
PC1 are configured as the pins SCL and SDA; PC3
is not driven and can be used as a general purpose
I/O pin. In the case of the STD SPI the pins PC0
and PC1 become the signals CLOCK and DATA,
PC3 is not driven and can be used as general purpose I/O pin. The VERIFY bit is available when the
SPI is configured as either S-BUS or I2CBUS. At
the start of a byte transmission, the verify bit is set
to one. If at any time during the transmission of the
following eight bits, the data on the SDA line does
not match the data forced by the SPI (while SCL is
high), then the VERIFY bit is reset. The verify is
available only during transmission for the S-BUS
and I2CBUS; for other protocol it is not defined.
The SDA and SCL signal entering the SPI are buffered in order to remove any minor glitches. When
STD bit is set to one (S-BUS or I2CBUS selected),
and TRX bit is reset (receiving data), and STOP bit
is set (last byte of current communication), the SPI
interface does not generate the Acknowledge, according to S-BUS/I2CBUS specifications. PCOSCL, PC1-SDA and PC3-SEN lines are standard
drive I/O port pins with open-drain output configuration (maximum voltage that can be applied to these
pins is VDD+ 0.3V).
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
S-BUS/I2CBUS Protocol Information
The S-BUS is a three-wire bidirectional data-bus
with functional features similar to the I2CBUS. In
fact the S-BUS includes decoding of Start/Stop
conditions and the arbitration procedure in case of
multimaster system configuration (the ST639x SPI
allows a single-master only operation). The SDA
line, in the I2CBUS represents the AND combination of SDA and SEN lines in the S-BUS. If the SDA
and the SEN lines are short-circuit connected, they
appear as the SDA line of the I2CBUS. The
Start/Stop conditions are detected (by the external
peripherals suited to work with S-BUS/I2CBUS) in
the following way:
- On S-BUS by a transition of the SEN line (1 to 0
Start, 0 to 1 Stop) while the SCL line is at high
level.
- On I2CBUS by a transition of the SDA line (10
Start, 01Stop) while the SCL line is at high
level.
Start and Stop condition are always generated by
the master (ST639x SPI can only work as single
master). The bus is busy after the start condition and
can be considered again free only when a certain
time delay is left after the stop condition. In the SBUS configuration the SDA line is only allowed to
change during the time SCL line is low. After the start
information the SEN line returns to high level and remains unchangedfor all the data transmission time.
When the transmission is completed the SDA line is
set to high level and, at the same time, the SEN line
returns to the low level in order to supply the stop information with a low to high transition, while the SCL
line is at high level. On the S-BUS, as on the I2CBUS,
each eight bit information (byte) is followed by one
acknowledged bit which is a high level put on the
SDA line by the transmitter. A peripheral that acknowledges has to pull down the SDA line during the
acknowledge clock pulse. An addressed receiver
has to generate an acknowledge after the reception
of each byte; otherwise the SDA line remains at the
high level during the ninth clock pulse time. In this
case the master transmitter can generate the Stop
condition, via the SEN (or SDA in I2CBUS) line, in
order to abort the transfer.
ST6391,92,93,95,97,99
SERIAL PERIPHERAL INTERFACE (Continued)
Start/Stop Acknowledge. The timing specs of the
S-BUS protocol require that data on the SDA (only
on this line for I2CBUS) and SEN lines be stable
during the “high” time of SCL. Two exceptions to
this rule are foreseen and they are used to signal
the start and stop condition of data transfer.
- On S-BUS by a transition of the SEN line (10
Start, 01 Stop) while the SCL line is at high
level.
- On I2CBUS by a transition of the SDA line (10
Start, 01 Stop) while the SCL line is at high
level.
Data are transmitted in 8-bit groups; after each
group, a ninth bit is interposed, with the purpose of
acknowledging the transmitting sequence (the
transmit device place a “1” on the bus, the acknowledging receiver a “0”).
Interface Protocol. This paragraph deals with the
description of data protocol structure. The interface protocol includes:
- A start condition
- A “slave chip address” byte, transmitted by the
master, containing two different information:
a. the code identifying the device the master
wants to address (this information is present in
the first seven bits)
b. the direction of transmission on the bus (this
information is given in the 8th bit of the byte);
“0” means “Write”, that is from the master to
the slave, while “1” means “Read”. The addressed slave must always acknowledge.
The sequence from, now on, is different according
to the value of R/W bit.
1. R/W = “0” (Write)
In all the following bytes the master acts as transmitter; the sequence follows with:
a. an optional data byte to address (if needed) the
slave location to be written (it can be a word address in a memory or a register address, etc.).
b. a “data” byte which will be written at the address given in the previous byte.
c. further data bytes.
d. a STOP condition
A data transfer is always terminated by a stop condition generated from the master. The ST639x peripheral must finish with a stop condition before
another start is given. Figure 44 shows an example
of write operation.
2. R/W = “1” (Read)
In this case the slave acts as transmitter and,
therefore, the transmission direction is changed. In
read mode two different conditions can be considered:
a. The master reads slave immediately after first
byte. In this case after the slave address sent
from the master with read condition enabled
the master transmitter becomes master receiver and the slave receiver becomes slave
transmitter.
b. The master reads a specified register or location of the slave. In this case the first sent byte
will contain the slave address with write condition enabled, then the second byte will specify
the address of the register to be read. At this
moment a new start is given together with the
slave address in read mode and the procedure
will proceed as described in previous point “a”.
35/64
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ST6391,92,93,95,97,99
SERIAL PERIPHERAL INTERFACE (Continued)
Figure 43.Master Transmit to Slave Receiver (Write Mode)
ACKNOWLEDGE
FROM SLAVE
ACKNOWLEDGE
FROM SLAVE
ACKNOWLEDGE
FROM SLAVE
MSB
S
SLAVE ADDRESS
0
A
WORD ADDRESS
A
DATA
A
STOP
R/W
START
P
Figure 44.Master Reads Slave Immediately After First Byte (read Mode)
ACKNOWLEDGE
FROM SLAVE
ACKNOWLEDGE
FROM MASTER
MSB
MSB
S
SLAVE ADDRESS
1
A
DATA
A
R/W
START
NO ACKNOWLEDGE
FROM MASTER
DATA
1
n BYTES
P
STOP
Figure 45.Master Reads After Setting Slave Register Address (Write Address, Read Data)
ACKNOWLEDGE
FROM SLAVE
ACKNOWLEDGE
FROM SLAVE
S
SLAVE ADDRESS
0
A
X
WORD ADDRESS
ACKNOWLEDGE
FROM SLAVE
ACKNOWLEDGE
FROM MASTER
START
1
NO ACKNOWLEDGE
FROM MASTER
MSB
MSB
SLAVE ADDRESS
P
STOP
R/W
START
S
A
A
DATA
R/W
A
DATA
1
P
STOP
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ST6391,92,93,95,97,99
SERIAL PERIPHERAL INTERFACE (Continued)
S-BUS/I2CBUS Timing Diagrams
The clock of the S-BUS/I2CBUS of the ST639x SPI
(single master only) has a fixed bus clock frequency of 62.5KHz. All the devices connected to
the bus must be able to follow transfers with fre-
quencies up to 62.5KHz, either by being able to
transmit or receive at that speed or by applying the
clock synchronization procedure which will force
the master into a wait state and stretch low periods.
Figure 46. S-BUS Timing Diagram
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ST6391,92,93,95,97,99
SERIAL PERIPHERAL INTERFACE (Continued)
Figure 47. I2C BUS Timing Diagram
2
Note: The third pin, SEN, should be high; it is not used in the I CBUS. Logically SDA is the AND of the S-BUS SDA and SEN.)
38/64
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ST6391,92,93,95,97,99
SERIAL PERIPHERAL INTERFACE (Continued)
Compatibility S-BUS/I2CBUS
Using the S-BUS protocol it is possible to implement mixed system including S-BUS/I2CBUS bus
peripherals. In order to have the compatibility with
the I2CBUS peripherals, the devices including the
S-BUS interface must have their SDA and SEN
pins connected together as shown in the following
Figure 48 (a and b). It is also possible to use mixed
S-BUS/I2CBUS protocols as showed in figure 46
(c). S-BUS peripherals will only react to S-BUS
protocol signals, while I2CBUS peripherals will
only react to I2CBUS signals. Multimaster configuration is not possible with the ST63XX SPI (single
master only).
Figure 48.S-BUS/I2C BUS Mixed Configurations
(a)
(b)
(c)
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ST6391,92,93,95,97,99
SERIAL PERIPHERAL INTERFACE (Continued)
Figure 49.Sofware Bus (Hardware Bus Disabled) Timing Diagram
STD SPI Protocol (Shift Register)
This protocol is similar to the I2CBUS with the exception that there is no acknowledge pulse and
there are no stop or start bits. The clock cannot be
slowed down by the externalperipherals.
In this case all three outputs should be high in order not to lock the software I/Os from functioning.
SPI Standard Bus Protocol: The standard bus
protocol is selected by loading the SPI Control
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
Register 1 (SCR1 Add. EBh). Bit 0 named I2C must
be set at one and bit 1 named STD mut be reset.
When the standard bus protocol is selected bit 2 of
the SCR1 is meaningless.
This bit named STOP bit is used only in I2CBUS or
SBUS. However take care thet THE STOP BIT
MUST BE RESET WHEN THE STANDARD PROTOCOL IS USED. This bit is set to ZERO after RESET.
ST6391,92,93,95,97,99
6-BIT PWM D/A CONVERTERS
The D/A macrocell contains up to six PWM D/A
outputs (31.25kHz repetition, DA0-DA5) with six bit
resolution.
Each D/A converter of ST639x is composed by the
following main blocks:
- pre-divider
- 6-bit counter
- data latches and compare circuits
The pre-divider uses the clock input frequency
(8MHz typical) and its output clocks the 6-bit freerunning counter. The data latched in the six registers (E0h, E1h, E2h, E3h, E6h and E7h) control the
six D/A outputs (DA0,1,2, 3, 4 and 5). When all zeros are loaded the relevant output is an high logic
level; all 1’s correspond to a pulse with a 1/64 duty
cycle and almost 100% zero level.
The repetition frequency is 31.25kHz and is related
to the 8MHz clock frequency. Use of a different oscillator frequency will result in a different repetition
frequency. All D/A outputs are open-drain with
standard current drive capability and able to withstand up to 12V.
AFC A/D COMPARATOR
AFC A/D INPUT,IR/PC6 RESULT, VSYNC RESULT
The AFC macrocell contains an A/D comparator
with five levels at intervals of 1V from 1V to 5V. The
levels can all be lowered by 0.5V to effectively double the resolution.
A/D Comparator
The A/D used to perform the AFC function (when
high threshold is selected) has the following voltage levels: 1,2,3,4 and 5V. Bits 0-2 of AFC result
register (E4h address) will provide the result in binary form (less than 1V is 000, greater than 5V is
101).
If the application requires a greater resolution, the
sensitivity can be doubled by clearing to zero bit 2
of the OUTPUTS control register, address E5h. In
this case all levels are shifted lower by 0.5V. If the
two results are now added within a software routine then the A/D S-curve can be located within a
resolution of 0.5V.
The A/D input has high impedance able to withstand up to 13V signals (input level tolerances
±200mV absolute and ± 100mv relative to 5V).
Figure 50. DA0-DA5 Data/Control Registers
Figure 52. AFC Inputs Configuration Diagram
DA0, DA1, DA2, DA3, DA4, DA5
DA0 to DA5 Data/control Registers
(E0h, E1h, E2h, E3h, E6h, E7h Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
Data Bit 0
Data Bit 1
Data Bit 2
Data Bit 3
Data Bit 4
Data Bit 5
Unused
Unused
DA0-DA5. These are the 6 bits of the PWM digital
to analog converter. Undefined after reset.
Figure 51.6-bit PWM D/A Output Configuration
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ST6391,92,93,95,97,99
AFC A/D COMPARATOR (Continued)
Figure 53. AFC, IR and OSD Result Register
AFCR
AFC Result Register
(E4h, Read Only)
D7 D6 D5 D4 D3 D2 D1 D0
AD2-AD0 A/D = Conv Result
IR
VSYNC
Unused
D7-D5. These bits are not used.
VSYNC. This bit reads the status of the VSYNC
pin. It is inverted with respect to the pin.
IR. This bit reads the status of the IR latch. If a signal has been latched this bit will be high.
AD2-AD0. These bits store the real time conversion of the value present on the AFC input pin. Undefined reset value.
Figure 54. Outputs Control Register
AFSR
AFC Shift Register
(E5h, Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
Unused
A/D Shift Bit
Unused
D7, D6, D5, D4, D3, D1, D0. These bits are not
used.
A/D Shift. This bit determines the voltage range of
the AFC input. Writing a zero will select the 0.5V to
4.5V range. Writing a one will select the 1.0V to
5.0V range. Undefined after reset.
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
DEDICATED LATCHES
Two latches are available which may generate interrupts to the ST639x core. The IR latch is set
either by the falling or rising edge of the signal on
pin PC6(IRIN). If bit 1 (IRPOSEDGE) of the latches
register (E9h) is high, then the latch will be triggered on the rising edge of the signal at PC6(IRIN).
If bit 1 (IRPOSEDGE) is low, then the latch will be
triggered on the falling edge of the signal at
PC6(IRIN). The IR latch can be reset by setting bit
3 (RESIRLAT) of the latches register; the bit is set
only and a high should be written every time the IR
latch needs to be reset. If bit 2 (IRINTEN) of the
latches register (E9h) is high, then the output of the
IR latch, IRINTN, may generate an interrupt (#0).
IRINTN is inverted with respect to the state of the
IR latch. If bit 2 (IRINTEN) is low, then the output of
the IR latch, IRINTN, is forced high. The state of
the IR latch may be read from bit 3 (IRLATCH) of
register E4h; if the IR latch is set, then bit 3 will be
high. The PWR latch is set either by the falling or
rising edge of the signal on pin PC4(PWRIN). If bit
4 (PWREDGE) of the latches register (E9h) is high,
then the latch will be triggered on the rising edge of
the signal at PC4(PWRIN). If bit 4 (PWREDGE) is
low, then the latch will be triggered on the falling
edge of the signal at PC4(PWRIN). The PWR latch
can be reset by setting bit 6 (RESPWRLAT) of the
latches register; the bit is set only and a high
should be written every time the PWR latch needs
to be reset. If bit 5 (PWRINTEN) of the latches register (E9h) is high, then the output of the PWR
latch, PWRINTN, may generate an interrupt (#4).
PWRINTN is inverted with respect to the state of
the PWR latch. If bit 5 (PWRINTEN) is low, then
the output of the PWR latch, PWRINTN, is forced
high.
ST6391,92,93,95,97,99
DEDICATED LATCHES(Continued)
Figure 55. Dedicated Latches Control Register
DLCR
Dedicated Latches Control
Register
(E9h, Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
Unused
IRPOSEDGE
IRINTEN
RESIRLAT
PWREDGE
PWRINTEN
RESPWRLAT
Unused
D7. This bit is not used
RESPWRLAT. Resets the PWR latch; this bit is set
only.
PWRINTEN. This bit enables the PWRINT signal
(#4) from the latch to the ST639x core. Undefined
after reset.
PWREDGE. The bit determines the edge which
will cause the PWRIN latch to be set. If this bit is
high, than the PWRIN latch will be set on the rising
edge of the PWRIN signal. Undefined after reset.
RESIRLAT. Resets the IR latch; this bit is set only.
IRINTEN. This bit enables the IRINTN signal (#0)
from the latch to the ST639x core. Undefined after
reset.
IRPOSEDGE. The bit determines the edge which
will cause the IR latch to be set. If this bit is high,
than the IR latch will be set on the rising edge of the
IR signal. Undefined after reset.
D0. This bit is not used
ON-SCREEN DISPLAY (OSD)
The ST639x OSD macrocell is a CMOS LSI character generator which enable display of characters
and symbols on the TV screen. The character
rounding function enhances the readability of the
characters. The ST639x OSD receives horizontal
and vertical synchronization signal and outputs
screen information via R, G, B and blanking pins.
The main characteristics of the macrocell are listed
below:
- Number of display characters: 5 lines by 15
columns.
- Number of character types: 128 characters in
two banks of 64 characters. Only one bank
per screen can be used.
- Character size: Four character heights (18H,
36H 54H, 72H), two heights are available per
screen, programmable by line.
- Character format: 6x9 dots with character
rounding function.
- Character colour: Eight colours available programmable by word.
- Display position: 64 horizontal positions by
2/fosc and 63 vertical positions by 4 H
- Word spacing: 64 positions programmable
from 2/fosc to 128/fosc.
- Line spacing: 63 positions programmable from
4 to 252 H.
- Background: No background, square background or fringe background programmable by
word.
- Background colour: Two of eight colours available programmable by word.
- Display output: Three character data output
terminals (R,G,B) and a blank output terminal.
- Display on/off: Display data may be programmed on or off by word or entire screen.
The entire screen may be blanked.
Format Specification
The entire display can be turned on or off through
the use of the global enable bit or the display may
be selectively turned on or off by word. To turn off
the entire display, the global enable bit (GE) should
be zero. If the global enable is one, the display is
controlled by the word enable bits (WE). Theglobal
enable bit is located in the global enable register
and the word enable bit is located in the space
character preceding the word.
43/64

ST6391,92,93,95,97,99
ON-SCREEN DISPLAY (Continued)
Each line must begin with a format character which
describes the format of that line and of the first
word. This character is not displayed.
A space character defines the format of subsequent words. A space character is denoted by a
one in bit 6 in the display RAM. If bit 6 of the display
RAM is a zero, the other six bits define one of the
64 display characters.
The colour, background and enable can be programmed by word. This information is encoded in
the space character between words or in the format character at the beginning of each line. Five
bits define the colour and background of the following word, and determine whether it will be displayed or not.
Characters are stored in a 6 x 9 dot format. One dot
is defined vertically as 2H (horizontal lines) and
horizontally as 2/fosc if the smallest character size
is enabled. There is no space between characters
or lines if the vertical space enable (VSE) and horizontal space enable (HSE) bits are both zero. This
allows the use of special graphics characters.
The normal alphanumeric character set is formatted to be 5 x 7 with one empty row at the top and
one at the bottom and one empty column at the
right. If VSE and HSE are both zero, then the spacing between alphanumeric characters is 1 dot and
the spacing between lines ofalphanumericcharacters is 2H.
The character size is programmed by line through
the use of the size bit (S) in the format character
and the global size bits (GS1 and GS2). The vertical spacing enable bit (VSE) located in the format
character controls the spacing between lines. If
this bit is set to one, the spacing between lines is
defined by the vertical spacing register, otherwise
the spacing between lines is 0.
The spacing between words is controlled by the
horizontal space enable bit (HSE) located in the
space character. If this bit is set to one, the spacing
between words is defined by the horizontal spacing
register, otherwise the space character width of 6
dots is the spacing between words.
The formats for the display character, space
character and format character are described
hereafter.
44/64

Figure 56. Space Character Register
Explanation
Space Character Format
See Data RAM Table Description
for Specific Address
( Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
HSE = Horizontal Space Enable
WE = Word Enable Bit
BGS = Backround Select
B = B Colour Bit
G = G Colour Bit
R = R Colour Bit
Fixed to “1”
Unuse d
D7. Not used.
D6. This pin is fixed to “1”.
R, G, B. Colour. The 3 colour control bits define the
colour of the following word as shown in Table below.
Space Character Register Colour Setting.
R
G
B
Colour
0
0
0
Black
0
0
1
Blue
0
1
0
Green
0
1
1
Cyan
1
0
0
Red
1
0
1
Magenta
1
1
0
Yellow
1
1
1
White
BGS. Background Select. The background select
bit selects the desired background for thefollowing
word. There are two possible backgrounds defined
by the bits in the Background Control Register.
“0” -The background on the following word is enabled by BG0 and the colour is set by R0, G0,
and B0.
“1” -The background on the following word is enabled by BG1 and the colour is set by R1, G1,
and B1.
ST6391,92,93,95,97,99
ON-SCREEN DISPLAY (Continued)
WE. Word Enable. The word enable bit defines
whether or not the following word is displayed.
“0” -The word is not displayed.
“1” -If the global enable bit is one, then the word is
displayed.
HSE. Horizontal Space Enable. The horizontal
space enable bit determines the spacing between
words. The space between characters is always 0.
The alphanumeric character set is implemented in
a 5 x 7 format with one empty column to the right
and one empty row above and below so that the
space between alphanumeric characters will be
one dot.
“0” -The space between words is equal to the width
of the space character, which is 6 dots.
“1” -The space between words is defined by the
value in the horizontal space register plus the
width of the space character.
“1” -The background on the following word is enabled by BG1 and the colour is set by R1, G1,
and B1.
WE. Word Enable. The word enable bit defines
whether or not the following word is displayed.
“0” -The word is not displayed.
“1” -If the global enable bit is one, then the word is
displayed.
VSE. Vertical Space Enable. The vertical space
enable bit determines the spacing between lines.
“0” -The space between lines is equal to 0H. The
alphanumeric character set is implemented in
a 5 x 7 format with one empty column to the
right and one empty row above and onebelow
and stored in a 6 x 9 format.
“1” -The space between lines is defined by the
value in the vertical space register.
Figure 57. Format Character Register
Explanation
Table 10. Format Character Register Colour
Setting.
Format Character
See Data RAM Table Description
for Specific Address
( Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
VSE = Vertical Space Enable
WE = Word Enable Bit
BGS = Backround Select
B = B Colour Bit
G = G Colour Bit
R = R Colour Bit
S = Character Size Control Bit
Unused
D7. This bit is not used
S. Character Size. The character size bit, along
with the global size bits (GS2 and GS1) located in
the horizontal space register, specify the character
size for each line as defined in Table 11.
R, G, B. Colour. The 3 colour control bits define the
colour of the following word as shown in Table 10.
BGS. Background Select. The background select
bit selects the desired background for thefollowing
word. There are two possible backgrounds defined
by the bits in the Background Control Register.
“0”- The background on the following word is enabled by BG0 and the colour is set by R0, G0,
and B0.
R
G
B
Colour
0
0
0
Black
0
0
1
Blue
0
1
0
Green
0
1
1
Cyan
1
0
0
Red
1
0
1
Magenta
1
1
0
Yellow
1
1
1
White
Table 11. Format Character Register Size
Setting
GS2 GS1
S
Vertical Height Horizontal length
0
0
0
18H
6 TDOT
0
0
1
36H
12 TDOT
0
1
0
18H
6 TDOT
0
1
1
54H
18 TDOT
1
0
0
36H
12 TDOT
1
0
1
54H
18 TDOT
1
1
0
36H
12 TDOT
1
1
1
72H
24 TDOT
TDOT= 2/fosc
D7. This bit is not used.
45/64

ST6391,92,93,95,97,99
ON-SCREEN DISPLAY (Continued)
Figure 58. Display Character Register
Explanation
Table 12. OSD Control Registers and Data
RAM Addressing
Display Character
See Data RAM Table Description
for specific Addresses
( Write Only)
Page
Address
Register or RAM
5
00h - 3Fh
RAM Locations 00h - 3Fh
6
00h - 0Fh
RAM Locations 00h - 0Fh
6
10h
Vertical Start Register
6
11h
Horizontal Start Register
6
12h
Vertical Space Register
6
13h
Horizontal Space Register
6
14h
Background Control Register
6
17h
Global Enable Register
No
Page
EDh
Character Bank Select Register
D7 D6 D5 D4 D3 D2 D1 D0
C5-C0 = Character Types
control Bit
Fixed to “0”
Unused
D6. This bit is fixed to “0”.
C5-C0. Character type. The 6 character type bits
define one of the 64 available character types.
These character types are shown on the following
pages.
Character Types
The character set is user defined as ROM mask
option.
Register and RAM Addressing
The OSD contains seven registers and 80 RAM locations. The seven registers are the Vertical Start
Address register, Horizontal Start Address register, Vertical Space register, Horizontal Space register, Background Control register, Global Enable
register and Character Bank Select register. The
Global Enable register can be written at any time
by the ST639x Core. The other six registers and
the RAM can only be read or written to if the global
enable is zero.
The six registers and the RAM are located on two
pages of the paged memory of the ST639x MCUs;
the Character Bank Select register is located outside the paged memory at address EDh. Each
page contains 64 memory locations. This paged
memory is at memory locations 00h to 3Fh in the
ST639x memory map. A page of memory is enabled by setting the desired page bit, located in the
Data Ram Bank Register, to a one. The page register is location E8h. A one in bit five selects page
5, located on the OSD and a one in bit 6 selects
page 6 on the OSD. Table 12 shows the addresses
of the OSD registers and RAM.
46/64

OSD Global Enable Register
This register contains the global enable bit (GE). It
is the only register that can be written at any time
regardless of the state of the GE bit. It is a write
only register.
Figure 59. Global Enable Bit
Global Enable
Register
17h - Page 6
( Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
GE = Global Enable Bit
Unuse d
D7-D1. These bits are not used
GE. Global Enable. This bit allows the entire display to be turned off.
“0” - The entire display is disabled. The RAM and
other registers of the OSD can be accessed by
the Core.
“1” - Display of words is controlled by the word enable bits (WE) located in the format or space
character. The other registers and RAM cannot be accessed by the Core.
ST6391,92,93,95,97,99
ON-SCREEN DISPLAY (Continued)
Figure 60. Vertical Start Address Register
Figure 61. Horizontal Start Address Register
VSAR
HSAR
Vertical Start Address Register
(10h - Page 6, Write Only)
Horizontal Start Address Register
(11h - Page 6, Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
VSA5-VSA0 = Vertical Start
Address bits
FR = Fringe Backround
Control bit
Unused
D7. This bit is not used
FR. Fringe Background.This bit changes the background from a box background to a fringe background. The background is enabled by word as
defined by either BG0 or BG1.
“0” -The background is defined to be a box which is
7 x 9 dots.
“1” -The background is defined to be a fringe.
VSA5-VSA0. Vertical Start Address. These bits
determine the start position of the first line in the
vertical direction. The 6 bits can specify 63 display
start positions of interval 4H. The first start position
will be the fourth line of the display. The vertical
start address is defined VSA0 by the following formula.
Vertical Start Address = 4H(25(VSA5) + 24(VSA4)
+ 23(VSA3) + 22(VSA2) + 21(VSA1) + 20(VSA0))
The case of all Vertical Start Address bits being
zero is illegal.
HSA5-HSA0 = Horizontal Start
Address bits
SBD = Space Blanking
Disabled bit
Unuse d
D7. This bit is not used.
SBD. Space Blanking Disable. This bit controls
whether or not the background is displayed when
outputting spaces. If two background colours are
used on adjacent words, then the background
should not be displayed on spaces in order to
make a nice break between colours. If an even
background around an area of text is desired, as in
a menu, then the background should be displayed
when outputting spaces.
“0” -The background during spaces is controlled by
the background enable bits (BG0 and BG1) located in the Background Control register.
“1” -The background is not displayed when outputting spaces.
HSA5, HSA0 - Horizontal Start Address bits.
These bits determine the start position of the first
character in the horizontal direction. The 6 bits can
specify 64 display start positions of interval 2/fosc or
400ns. The first start position will be at 4.0µs because of the time needed to access RAM and
ROM before the first character can be displayed.
The horizontal start address is defined by the following formula.
Horizontal Start Address = 2/fosc(10.0 + 25(HSA5)
+ 24(HSA4) + 23(HSA3) + 22(HSA2) + 21(HSA1) +
20(HSA0))
47/64

ST6391,92,93,95,97,99
ON-SCREEN DISPLAY (Continued)
Figure 63. Horizontal Space Register
Figure 62. Vertical Space Register
VSR
HSR
Vertica l Space Register
(12h - Page 6, Write Only)
Horizontal Space Register
(13h - Page 6, Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0
VS5-VS0 = Vertical Space
HS5-HS0 = Horizontal Space
SCB = Screen Blanking bit
GS1 = Global Size Bit 1
Unused
GS2 = Global Size Bit 2
D7. This bit is not used
SCB. Screen Blanking. This bit allows the entire
screen to be blanked.
“0” -The blanking output signal (VBLK) is active
only when displaying characters.
“1” -The blanking output signal (VBLK) is always
active. Characters in the display RAM are still
displayed.
When this bit is set to one, the screen is blanked
also without setting the Global Enable bit to one
(OSD disabled).
VS5 , VS0. Vertical Space. These bits determine
the spacing between lines if the Vertical Space Enable bit (VSE) in the format character is one. If VSE
is zero there will be no spaces between lines. The
Vertical Space bits can specify one of 63 spacing
values from 4H to 252H. The space between lines
is defined by the following formula.
Space between lines = 4H(25(VS5) + 24(VS4) +
23(VS3) + 22(VS2) + 21(VS1) + 20(VS0))
The case of all Vertical Start Address bits being
zero is illegal.
48/64

GS2,GS1. Global Size. These bits along with the
size bit (S) located in the Character format word
specify the character size for each line as defined
in Table 13.
Table 13. Horizontal Space Register Size
Setting.
GS2 GS1
S
Vertical Height
Horizontal
Length
0
0
0
18H
6 TDOT
0
0
1
36H
12 TDOT
0
1
0
18H
6 TDOT
0
1
1
54H
18 TDOT
1
0
0
36H
12 TDOT
1
0
1
54H
18 TDOT
1
1
0
36H
12 TDOT
1
1
1
72H
24 TDOT
Note: TDOT= 2/fOSC
HS5, HS0 . Horizontal Space . These bits determine the spacing between words if the Horizontal
Space Enable bit (HSE) located in the space character is a one. The space between words is then
equal to the width of the space character plus the
number of tdots specified by the Horizontal Space
bits. The 6 bits can specify one of 64 spacing values ranging from 2/fosc to 128/fosc. The formula is
shown below for the smallest size character(18H).
If larger size characters are being displayed the
spacing between words will increase proportionately. Multiply the value below by 2, 3 or 4 for character sizes of 36H, 54H and 72H respectively.
Space between words (not including the space
character)=2/fosc(1+25(HS5)+24(HS4)+23(HS3)
+22(HS2)+ 21(HS1)+20(HS0))
ST6391,92,93,95,97,99
ON-SCREEN DISPLAY (Continued)
Background Control Register
This register sets up two possible backgrounds.
The background select bit (BGS) in the format or
space character will determine which background
is selected for the current word.
Figure 64. Backround Control Register
Figure 65. Character Bank Select Register
CBSR
Character Bank Select Register
(EDh - No Page , Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
BCR
BS = Bank Select Bit
Unuse d
Backround Control Register
(14h - Page 6, Write Only)
D7 D6 D5 D4 D3 D2 D1 D0
BK0 = Backround Enable Bit 0
BK1 = Backround Enable Bit 1
B0 = B Colour Backround Bit 0
B1 = B Colour Backround Bit 1
G0 = G Colour Backround Bit 0
G1 = G Colour Backround Bit 1
R0 = R Colour Backround Bit 0
R1 = R Colour Backround Bit 1
R1,R0,G1,G0,B1,B0. Background Colour.
These bits define the colour of the specified background, either background 1 or background 0 as
defined in Table below.
Table 14. Background Register Colour
Setting.
RX
GX
BX
Colour
0
0
0
Black
0
0
1
Blue
0
1
0
Green
0
1
1
Cyan
1
0
0
Red
1
0
1
Magenta
1
1
0
Yellow
1
1
1
White
BK1,BK0. Background Enable.These bits determine if the specified background is enabled or not.
“0” -The following word does not have a background.
“1” -There is a background around the following
word.
D7-D1. These bits are not used
BS. Bank Select. This bit select the character bank
to be used. The lower bank is selected with 0. The
value can be modified only when the OSD is OFF
(GE=0). No reset value.
OSD Data RAM
The contents of the data RAM can be accessed by
the ST639x MCUs only when the global enable bit
(GE) in the Global Enable register is a zero.
The first character in every line is the format character. This character is not displayed. It defines the
size of the characters in the line and contains the
vertical space enable bit. This character also defines the colour, background and display enable for
the first word in the line. Subsequent characters
are either spaces or one of the 64 available character types.
The space character defines the colour, background, display enable and horizontal space enable for the following word. Since there are 5
display lines of 15 characters each, the display
RAM must contain 5 lines x (15 characters + 1 format character) or 80 locations. The RAM size is 80
locations x 7 bits. The data RAM map is shown in
Table 15.
49/64

ST6391,92,93,95,97,99
ON-SCREEN DISPLAY (Continued)
Table 15. OSD RAM Map
Column
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
A0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
A1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
A2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
A3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
Page
A5
A4
LINE
5
0
0
1
FT
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
5
0
1
2
FT
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
5
1
0
3
FT
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
5
1
1
4
FT
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
6
0
0
5
FT
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
Ch
AVAILABLE SCREEN SPACE
Notes: FT. The format character required for each line. Characters
in columns 1 thru 15 are displayed.
Ch. (Byte) Character (Index into OSD character generator) or
space character
Emulator Remarks
There are a few differences between emulator and
silicon. For noise reasons, the OSD oscillator pins
are not available: the internal oscillator cannot be
disabled and replaced by an external coil. In the
emulator, the Character Bank Select register can
be written also with Global Enable bit set, while this
is not allowed in the device.
Application Notes
1 - The OSD character generator is composed of a
dual port video ram and some circuitry. It needs
two input signals VSYNC and HSYNC to syncronize its dedicated oscillator to the TV picture. It generates 4 output signals, that can be used from the
TV set to generate the characters on the screen.
For instance, they can be used to feed the SCART
plug, providing an adequate buffer to drive the low
impedance (75 Ω) of the SCART inputs.
2 - The Core sees the OSD as a number of RAM
locations (80) plus a certain number of control registers (6). These 86 locations are mapped in two
pages of the dynamic data ram address range
(0h..3Fh).
50/64

In page 5 (load 20H in the register 0E8h), there are
64 bytes of RAM, the ones of the first 4 rows (16
bytes each row, 15 characters per row maximum,
plus an hidden leading formatcharacter). In page 6
(load 40H in register 0E8h), the 16 bytes of the fifth
row (0..0Fh), and the 6 control registers
(10H..14H,17H).
3 - The video RAM is a dual port ram. That means
that it can be addressed either from the Core or
from the OSD circuitry itself. To reduce the complexity of the circuitry, and thus its cost, some restrictions have been introduced in the use of the
OSD.
a. The Core can Only write to any of the 86 locations (either video RAM or control registers).
b. The Core can Only write to any of the leading
85 locations when the OSD oscillator is OFF.
Only the last location (control register 17H in
page 6) can be addressed at any time. This is
the Global Enable Register, which contains
only the GE bit. If it is set, the OSD is on, if it is
reset the OSD is off.
4 - The timing of the on/off switching of the OSD
oscillator is the following:
a. GE bit is set. The OSD oscillator will start on
the next VSYNC signal.
b. GE bit is reset. The OSD oscillator will be immediately switched off.
ST6391,92,93,95,97,99
ON-SCREEN DISPLAY (Continued)
To avoid a bad visual impression, it is important
that the GE bit is set before the end of the flyback
time when changing characters. This can be done
inside the VSYNC interrupt routine. The following
diagram can explain better:
Figure 66. OSD Oscillator ON/OFF Timing
Notes: A - Picture time: 20 mS in PAL/SECAM.
B - VSYNC interrupt, if enabled.
C - Starting of OSD oscillator, if GE = 1.
D - Flyback time.
When modifying the picture display (i.e.: a bar
graph for an analog control), it is important that the
switching on of the GE bit is done before the the
end of the flyback time (D in Figure 66). If the GE
bit is set after the end of the flyback time then the
OSD will not start until the begining of the next
frame. This results in one frame being lost and will
result in a Flicker on the screen. One method to be
sure to avoid the flicker is to wait for the VSYNC interrupt at the start of the flyback; once the VSYNC
interrupt is detected, then the GE bit can be set to
zero, the characters changed, and the GE set to
one. All this should occur before the end of the flyback time in order not to lose a frame. The correct
edge of the interrupt must be chosen.
The VSYNC pin may alternatively be sampled by
software in order to know the status; this can be
done by reading bit 4 of register E4h; this bit is inverted with respect to the VSYNC pin.
6 - An OSD end of line Bar is present in the
ST63P9x piggyback and ST639x ROM, EPROM
and OTP devices when using the background
mode. If this bar is present with software running in
the piggybacks then it is also present on the ROM
mask version. If the end of line bar is seen to be
eliminated by software in the piggyback, then it is
also be eliminated in the ROM mask version.
The bar appears at the end of the line in the background mode when the last character is a space
character, the first format character is defined with
S=0 (size 0)and the backround is not displayed
during the space. The bar is the colour of the background defined by the space character. To eliminate the bar:
a. If two backgrounds are used then the bar
should be moved off the screen by using large
word spaces instead of character spaces. If
there are not enough spaces before the end of
the line, then the location of the valid characters should be moved so they appear at the
end of the line (and hence no bar); positioning
can be compensated using the horizontal start
register.
b. If only one background is used, then the other
background should be transparent in order to
eliminate the bar.
7 - The OSD oscillator external network should
consist of a capacitor on each of the OSD oscillator
pins to ground together with an inductance between pins. The user should select the two capacitors to be the same value (15pF to 25pF each is
recommended). The inductance is chosen to give
the desired OSD oscillator frequency for the application (typically 56µH).
51/64

ST6391,92,93,95,97,99
SOFTWARE DESCRIPTION
The ST63xx software has been designed to fully
use the hardware in the most efficient way possible
while keeping byte usage to a minimum; in short to
provide byte efficient programming capability. The
ST63xx Core has the ability to set or clear any
register or RAM location bit of the Data space with
a single instruction. Furthermore, the program may
branch to a selected address depending on the
status of any bit of the Data space. The carry bit is
stored with the value of the bit when the SET or
RES instruction is processed.
Addressing Modes
The ST63xx Core has nine addressing modes
which are described in the following paragraphs.
The ST63xx Core uses three different address
spaces : Program space, Data space, and Stack
space. Program space contains the instructions
which are to be executed, plus the data for immediate mode instructions. Data space contains the
Accumulator, the X,Y,V and W registers, peripheral
and Input/Outputregisters, the RAM locations and
Data ROM locations (for storage of tables and
constants). Stack space contains six 12-bit RAM
cells used to stack the return addresses for subroutines and interrupts.
Immediate. In the immediate addressing mode,
the operand of the instruction follows the opcode
location. As the operand is a ROM byte, the immediate addressing mode is used to access constants
which do not change during program execution
(e.g., a constant used to initialize a loop counter).
Direct. In the direct addressing mode, the address
of the byte that is processed by the instruction is
stored in the location that follows the opcode. Direct
addressing allows the user to directly address the
256 bytes in Data Space memory with a single
two-byte instruction.
Short Direct. The Core can address the four RAM
registers X,Y,V,W (locations 80H, 81H, 82H, 83H)
in the short-direct addressing mode. In this case,
the instruction is only one byte and the selection of
the location to be processed is contained in the
opcode. Short direct addressing is a subset of the
direct addressing mode. (Note that 80H and 81H
are also indirect registers).
Extended. In the extended addressing mode, the
12-bit address needed to define the instruction is
obtained by concatenating the four less significant
bits of the opcode with the byte following the opcode. The instructions (JP, CALL) that use the
extended addressing mode are able to branch to
any address of the 4K bytes Program space.
An extended addressing mode instruction is twobyte long.
52/64

Program Counter Relative. The relative addressing mode is only used in conditional branch instructions. The instruction is used to perform a test and,
if the condition is true, a branch with a span of -15
to +16 locations around the address of the relative
instruction. If the condition is not true, the instruction that follows the relative instruction is executed.
The relative addressing mode instruction is onebyte long. The opcode is obtained in adding the
three most significant bits that characterize the kind
of the test, one bit that determines whether the
branch isa forward (when it is 0) or backward (when
it is 1) branch and the four less significant bits that
give the span of the branch (0h to Fh) that must be
added or subtracted to the address of the relative
instruction to obtain the address of the branch.
Bit Direct. In the bit direct addressing mode, the
bit to be set or cleared is part of the opcode, and
the byte following the opcode points to the address
of the byte in which the specified bit must be set or
cleared. Thus, any bit in the 256 locations of Data
space memory can be set or cleared.
Bit Test & Branch. The bit test and branch addressing mode is a combination of direct addressing and relative addressing. The bit test and branch
instruction is three-byte long. The bit identification
and the tested condition are included in the opcode
byte. The address of the byte to be tested follows
immediately the opcode in the Program space. The
third byte is the jump displacement, which is in the
range of -126 to +129. This displacement can be
determined using a label, which is converted by the
assembler.
Indirect. In the indirect addressing mode, the byte
processed by the register-indirect instruction is at
the address pointed by the content of one of the
indirect registers, X or Y (80H,81H). The indirect
register is selected by the bit 4 of the opcode. A
register indirect instruction is one byte long.
Inherent. In the inherent addressing mode, all the
information necessary to execute the instruction is
contained in the opcode. These instructions are
one byte long.
ST6391,92,93,95,97,99
SOFTWARE DESCRIPTION (Continued)
Instruction Set
The ST63xx Core has a set of 40 basic instructions. When these instructions are combined with
nine addressing modes, 244 usable opcodes can
be obtained. They can be divided into six different
types:load/store, arithmetic/logic, conditional
branch, control instructions, jump/call, bit manipulation. The following paragraphs describe the different types.
All the instructions within a given type are presented in individual tables.
Load & Store. These instructions use one,two or
three bytes in relation with the addressing mode.
One operand is the Accumulator for LOAD and the
other operand is obtained from data memory using
one of the addressing modes.
For Load Immediate one operand can be any of the
256 data space bytes while the other is always
immediate data. See Table 16.
Table 16. Load & Store Instructions
Instruction
LD A, X
Addressing Mode
Bytes
Short Direct
1
Flags
Cycles
4
Z
C
∆
*
LD A, Y
Short Direct
1
4
∆
*
LD A, V
Short Direct
1
4
∆
*
LD A, W
Short Direct
1
4
∆
*
LD X, A
Short Direct
1
4
∆
*
LD Y, A
Short Direct
1
4
∆
*
LD V, A
Short Direct
1
4
∆
*
LD W, A
Short Direct
1
4
∆
*
LD A, rr
Direct
2
4
∆
*
LD rr, A
Direct
2
4
∆
*
LD A, (X)
Indirect
1
4
∆
*
LD A, (Y)
Indirect
1
4
∆
*
LD (X), A
Indirect
1
4
∆
*
LD (Y), A
Indirect
1
4
∆
*
LDI A, #N
Immediate
2
4
LDI rr, #N
Immediate
3
4
∆
*
*
*
Notes:
X,Y. Indirect Register Pointers, V & W Short Direct Registers
# . Immediate data (stored in ROM memory)
rr. Data space register
∆ . Affected
* . Not Affected
53/64

ST6391,92,93,95,97,99
SOFTWARE DESCRIPTION (Continued)
Arithmetic and Logic. These instructions are
used to perform the arithmetic calculations and
logic operations. In AND, ADD, CP, SUB instructions one operand is always the accumulatorwhile
the other can be either a data space memory
content or an immediate value in relation with the
addressing mode. In CLR, DEC, INC instructions
the operand can be any of the 256 data space
addresses. In COM, RLC, SLA the operand is
always the accumulator. See Table 17.
Table 17. Arithmetic & Logic Instructions
Instruction
Addressing Mode
ADD A, (X)
ADD A, (Y)
ADD A, rr
Indirect
Indirect
Direct
ADDI A, #N
Immediate
AND A, (X)
AND A, (Y)
AND A, rr
Indirect
Indirect
Direct
ANDI A, #N
Immediate
CLR A
CLR rr
Short Direct
Direct
COM A
Inherent
CP A, (X)
CP A, (Y)
CP A, rr
Indirect
Indirect
Direct
CPI A, #N
Immediate
2
DEC
DEC
DEC
DEC
DEC
DEC
DEC
DEC
Short Direct
Short Direct
Short Direct
Short Direct
Direct
Direct
Indirect
Indirect
1
1
1
1
INC
INC
INC
INC
INC
INC
INC
INC
X
Y
V
W
A
rr
(X)
(Y)
X
Y
V
W
A
rr
(X)
(Y)
Bytes
1
1
4
4
2
4
2
4
1
1
4
4
2
4
2
4
2
3
1
1
1
1
*
*
*
∆
*
∆
*
4
∆
∆
4
4
4
4
∆
∆
∆
∆
∆
∆
∆
∆
*
*
*
*
*
*
*
*
4
4
4
4
∆
∆
∆
∆
∆
∆
∆
∆
*
*
*
*
*
*
*
*
4
4
1
1
∆
∆
∆
∆
∆
∆
4
4
2
2
∆
∆
∆
∆
4
4
1
1
∆
∆
4
2
2
∆
∆
∆
∆
4
4
2
C
∆
∆
∆
*
4
1
1
Z
∆
4
4
1
Short Direct
Short Direct
Short Direct
Short Direct
Direct
Direct
Indirect
Indirect
Flags
Cycles
4
4
RLC A
Inherent
1
4
∆
∆
SLA A
Inherent
2
4
∆
∆
SUB A, (X)
SUB A, (Y)
SUB A, rr
Indirect
Indirect
Direct
∆
∆
∆
∆
∆
∆
SUBI A, #N
Immediate
∆
∆
1
1
4
4
2
4
2
Notes:
X,Y. Indirect Register Pointers, V & W Short Direct Registers
# . Immediate data (stored in ROM memory)
rr. Data space register
∆. Affected
* . Not Affected
54/64

4
ST6391,92,93,95,97,99
SOFTWARE DESCRIPTION (Continued)
Conditional Branch. The branch instructions
achieve a branch in the program when the selected
condition is met. See Table 18.
Bit ManipulationInstructions. These instructions
can handle any bit in data space memory. One
group either sets or clears. The other group (see
Conditional Branch) performs the bit test branch
operations. See Table 19.
Control Instructions. The control instructions
control the MCU operations during program execution. See Table 20.
Jump and Call. These two instructions are used to
perform long (12-bit) jumps or subroutines call
inside the whole program space. Refer to Table 21.
Table 18. Conditional Branch Instructions
Instruction
Branch If
JRC e
JRNC e
JRZ e
JRNZ e
JRR b, rr, ee
JRS b, rr, ee
C=1
C=0
Z=1
Z=0
Bit = 0
Bit = 1
Bytes
Cycles
1
1
1
1
3
3
2
2
2
2
5
5
Notes:
b. 3-bit address
rr. Data space register
e. 5 bit signed displacement in the range -15 to +16
ee. 8 bit signed displacement in the range -126 to +129
∆
Flags
Z
C
*
*
*
*
*
*
*
*
*
*
∆
∆
. Affected
* . Not Affected
Table 19. Bit Manipulation Instructions
Instruction
Addressing
Mode
SET b,rr
RES b,rr
Bit Direct
Bit Direct
Notes:
b. 3-bit address;
rr. Data space register;
Bytes
Cycles
2
2
4
4
Bytes
Cycles
1
1
1
1
1
2
2
2
2
2
Flags
Z
C
*
*
*
*
* . Not Affected
Table 20. Control Instructions
Instruction
Addressing
Mode
NOP
RET
RETI
STOP (1)
WAIT
Inherent
Inherent
Inherent
Inherent
Inherent
Flags
Z
C
*
*
∆
*
*
*
*
∆
*
*
Notes:
1. This instruction is deactivated and a WAITis automatically executed instead of a STOP if the hardware activated
watchdog function is selected.
∆ . Affected
* . Not Affected
Table 21. Jump & Call Instructions
Instruction
Addressing
Mode
CALL abc
JP abc
Extended
Extended
Bytes
Cycles
2
2
4
4
Flags
Z
C
*
*
*
*
Notes:
abc.12-bit address;
* . Not Affected
55/64

ST6391,92,93,95,97,99
SOFTWARE DESCRIPTION (Continued)
Opcode Map Summary. The following table containsan opcode map for the instructions used on the MCU.
Low
Low
0
0000
1
0001
2
0010
3
0011
2 JRNZ
e
1
pcr
2 JRNZ
e
1
pcr
2 JRNZ
e
1
pcr
4 CALL
abc
2
ext
4 CALL
abc
2
ext
4 CALL
abc
2
ext
2 JRNC
e
1
pcr
2 JRNC
e
1
pcr
2 JRNC
e
1
pcr
5 JRR
b0 ,rr,ee
3
bt
5 JRS
b0 ,rr,ee
3
bt
5 JRR
b4 ,rr,ee
3
bt
4
010 0
5
0101
6
0110
7
0111
8
10 00
9
1001
A
1010
B
1011
2 JRNC
e
1
pcr
2 JRNC
e
1
pcr
2 JRNC
e
1
pcr
4 RES
b0 ,rr
2
b.d
4 SET
b0 ,rr
2
b.d
4 RES
b4 ,rr
2
b.d
C
1100
D
1101
E
1110
LDI
rr,nn
3 imm
4 DEC
x
1
sd
4 COM
a
1
inh
2 JRC
e
1
pcr
2 JRC
e
1
pcr
2 JRC
e
1
pcr
F
1111
Hi
0
00 00
1
00 01
2
00 10
3
0011
4
01 00
5
0101
6
0110
7
0111
8
1000
9
1001
A
1010
B
1011
C
1100
D
1101
E
1110
F
1111
Hi
2
1
2
1
2
1
JRZ
2 JRC
e
#
e
pcr
1
prc
JRZ 4 INC 2 JRC
e
x
e
pcr 1
sd 1
prc
JRZ
2 JRC
e
#
e
pcr
1
prc
4
LD
a,(x)
1
ind
4 LDI
a,n n
2 imm
4
CP
a,(x)
1
ind
2 JRNZ
e
1
pcr
2 JRNZ
e
1
pcr
2 JRNZ
e
1
pcr
2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4
LD 2 JRC 4 CPI 2 JRNZ
e
abc
e
b4 ,rr,ee
e
a,x
e
a,nn
e
1
pcr 2
ext 1
pcr 3
bt 1
pcr 1
sd 1
prc 2 imm 1
pcr
2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ
2 JRC 4 ADD 2 JRNZ
e
abc
e
b2 ,rr,ee
e
#
e
a,(x)
e
1
pcr 2
ext 1
pcr 3
bt 1
pcr
1
prc 1
ind 1
pcr
2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4 INC 2 JRC 4 ADDI 2 JRNZ
e
abc
e
b2 ,rr,ee
e
y
e
a,n n
e
1
pcr 2
ext 1
pcr 3
bt 1
pcr 1
sd 1
prc 2 imm 1
pcr
2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ
2 JRC 4 INC 2 JRNZ
e
abc
e
b6 ,rr,ee
e
#
e
(x)
e
1
pcr 2
ext 1
pcr 3
bt 1
pcr
1
prc 1
ind 1
pcr
2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4
LD 2 JRC
2 JRNZ
e
abc
e
b6 ,rr,ee
e
a,y
e
#
e
1
pcr 2
ext 1
pcr 3
bt 1
pcr 1
sd 1
prc
1
pcr
2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ
2 JRC 4
LD 2 JRNZ
e
abc
e
b1 ,rr,ee
e
#
e
(x),a
e
1
pcr 2
ext 1
pcr 3
bt 1
pcr
1
prc 1
ind 1
pcr
2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4 INC 2 JRC
2 JRNZ
e
abc
e
b1 ,rr,ee
e
v
e
#
e
1
pcr 2
ext 1
pcr 3
bt 1
pcr 1
sd 1
prc
1
pcr
2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ
2 JRC 4 AND 2 JRNZ
e
abc
e
b5 ,rr,ee
e
#
e
a,(x)
e
1
pcr 2
ext 1
pcr 3
2 JRNZ 4 CALL 2 JRNC 5
e
1
pcr 2
abc
ext 1
e
bt 1
JRS 2
pcr
JRZ 4
4
2
4
2
4
2
4
2
4
2
4
2
4
2
4
2
4
2
4
2
4
1
prc 1
ind 1
pcr 2
LD 2 JRC 4 ANDI 2 JRNZ 4
#
1
pcr 2
ext 1
pcr 3
2 JRNZ 4 CALL 2 JRNC 5
1
prc 1
ind 1
pcr 2
INC 2 JRC 4 SUBI 2 JRNZ 4
e
pcr 2
2 JRNZ
e
1
pcr
2 JRNZ
e
1
pcr
abc
ext 1
4 CALL
abc
2
ext
4 CALL
abc
2
ext
e
2
1
2
1
2
1
JRZ
e
pcr
JRZ
e
pcr
JRZ
e
pcr
4
4
LD
a,(y)
1
ind
4
LD
a,rr
2
dir
4
CP
a,(y)
1
ind
JP 2 JRNC 4 SET 2 JRZ 4
LD 2 JRC 4
CP
abc
e
b4 ,rr
e
x,a
e
a,rr
ext 1
pcr 2 b.d. 1
JP 2 JRNC 4 RES 2
pcr 1
sd 1
pcr 2
dir
JRZ 2 RETI 2 JRC 4 ADD
abc
e
b2 ,rr
e
ext 1
pcr 2
b.d 1
pcr 1
JP
abc
ext
JP
abc
ext
JP
abc
ext
JP
abc
ext
JP
abc
ext
JP
abc
2 JRNC
e
1
pcr
2 JRNC
e
1
pcr
2 JRNC
e
1
pcr
2 JRNC
e
1
pcr
2 JRNC
e
1
pcr
2 JRNC
e
4 SET
b2 ,rr
2
b.d
4 RES
b6 ,rr
2
b.d
4 SET
b6 ,rr
2
b.d
4 RES
b1 ,rr
2
b.d
4 SET
b1 ,rr
2
b.d
4 RES
b5 ,rr
2
1
2
1
2
1
2
1
2
1
2
ext 1
pcr 2
b.d 1
JP 2 JRNC 4 SET 2
JRZ
e
pcr
JRZ
e
pcr
JRZ
e
pcr
JRZ
e
pcr
JRZ
e
pcr
JRZ
e
e
inh 1
pcr 1
a,(y)
ind
DEC 2 JRC 4 ADD
y
e
a,rr
1
sd 1
pcr 2
dir
2 STOP 2 JRC 4 INC
e
(y)
1
inh 1
pcr 1
ind
4
LD 2 JRC 4 INC
y,a
e
rr
1
sd 1
pcr 2
dir
2 JRC 4
LD
#
e
(y),a
1
pcr 1
ind
4 DEC 2 JRC 4
LD
v
e
rr,a
1
sd 1
pcr 2
dir
4 RLC 2 JRC 4 AND
a
e
a,(y)
bt 1
JRS 2
pcr
JRZ 4
pcr 1
JRZ 4
2 JRC 4 SUB 2 JRNZ 4
JP 2 JRNC 4 RES 2 JRZ 2
e
a,(x)
e
abc
e
b3 ,rr
e
ext 1
pcr 2
JP 2 JRNC 4
b.d 1
SET 2
inh 1
pcr 1
ind
LD 2 JRC 4 AND
RET 2 JRC 4 SUB
e
a,(y)
pcr 1
inh 1
pcr 1
ind
JRZ 4 DEC 2 JRC 4 SUB
b3 ,rr,ee
e
w
e
a,n n
e
abc
e
b3 ,rr
e
w
e
a,rr
pcr 3
bt 1
pcr 1
sd 1
prc 2 imm 1
pcr 2
ext 1
pcr 2
b.d 1
pcr 1
sd 1
pcr 2
dir
2 JRNC
e
1
pcr
2 JRNC
e
1
pcr
5 JRR
b7 ,rr,ee
3
bt
5 JRS
b7 ,rr,ee
3
bt
2
JRZ
e
#
1
pcr
2 JRZ 4
LD
e
a,w
1
pcr 1
sd
2 JRC 4 DEC
e
(x)
1
prc 1
ind
2 JRC
e
#
1
prc
Abbreviations for Addressing Modes:
Legend:
dir
Direct
# Indicates Illegal Instructions
sd
Short Direct
e 5 Bit Displacement
imm Immediate
b 3 Bit Address
inh
Inherent
rr1byte dataspace address
ext
Extended
nn 1 byte immediate data
b.d
Bit Direct
abc 12 bit address
bt
Bit Test
ee 8 bit Displacement
pcr
Program Counter Relative
ind
Indirect
56/64

2 JRNZ
e
1
pcr
2 JRNZ
e
1
pcr
4
JP
abc
2
ext
4
JP
abc
2
ext
2 JRNC
e
1
pcr
2 JRNC
e
1
pcr
4 RES
b7 ,rr
2
b.d
4 SET
b7 ,rr
2
b.d
2
JRZ
e
1
pcr
2 JRZ
e
1
pcr
0
0000
1
0001
2
0010
3
0011
4
0100
4
b5 ,rr,ee
e
a,v
e
a,nn
e
abc
e
b5 ,rr
e
v,a
e
a,rr
pcr 3
bt 1
pcr 1
sd 1
prc 2 imm 1
pcr 2
ext 1
pcr 2
b.d 1
pcr 1
sd 1
pcr 2
dir
2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ
e
abc
e
b3 ,rr,ee
e
1
JP
abc
ext
JP
abc
ext
JP
abc
ext
2 WAIT 2 JRC
e
1
inh 1
pcr
4
LD 2 JRC
w,a
e
1
sd 1
pcr
Cycles
Operand
Bytes
Addressing Mode
2 JRC
e
1
pcr
4 DEC
(y)
1
ind
4 DEC
rr
2
dir
5
0101
6
0110
7
0111
8
1000
9
1001
A
1010
B
1011
C
1100
D
1101
E
1110
F
1111
Mnemonic
ST6391,92,93,95,97,99
ABSOLUTE MAXIMUM RATINGS
This product contains devices to protect the inputs
against damage due to high static voltages, however it is advised to take normal precaution to avoid
application of any voltage higher than maximum
rated voltages.
For proper operation it is recommended that VI and
VO must be higher than VSS and smaller than VDD.
Reliability is enhanced if unused inputs are connected to an appropriated logic voltage level (VDD
or VSS).
Symbol
VDD
Power Considerations. The average chip-junction temperature, Tj, in Celsius can be obtained
from :
Tj =
TA + PD x RthJA
Ambient Temperature.
Where :TA =
RthJA = Package thermal resistance
(junction-to ambient).
PD =
Pint + Pport.
Pint = IDD x VDD (chip internal power).
Pport = Port power dissipation
(determinated by the user).
Parameter
Value
Supply Voltage
Unit
-0.3 to 7.0
V
VI
Input Voltage (AFC IN)
VI
Input Voltage (Other Inputs)
VO
Output Voltage (PA4-PA7, PC4-PC7, DA0-DA5)
VO
Output Voltage (Other Outputs)
IO
Current Drain per Pin Excluding V DD, VSS, PA6, PA7
± 10
mA
IO
Current Drain per Pin (PA6, PA7)
± 50
mA
V
- 0.3 to +13
V
- 0.3 to VDD +0.3
V
SS
V
SS
VSS - 0.3 to +13
V
V
- 0.3 to VDD +0.3
SS
IVDD
Total Current into VDD (source)
50
mA
IVSS
Total Current out of VSS (sink)
150
mA
V
°C
Tj
Junction Temperature
150
TSTG
Storage Temperature
-60 to 150
°C
Note : Stresses above those listed as “absolute maximum ratings” may cause permanent damage to the device . This is a stress rating only
and functional operation of the device at these conditions is not implied. Exposure to maximum rating conditions for extended periods may
affect device reliability.
THERMAL CHARACTERISTIC
Symbol
Parameter
Value
Test Conditions
Min.
RthJA
Thermal Resistance
PSDIP42
Unit
Typ.
67
Max.
°C/W
RECOMMENDED OPERATING CONDITIONS
Symbol
Parameter
Value
Test Conditions
Min.
TA
Operating Temperature
VDD
Operating Supply Voltage
fOSC
Oscillator Frequency
RUN & WAIT Modes
fOSDOSC
1 Suffix Version
4.5
Max.
0
5.0
6.0
70
°C
8.1
MHz
8.0
MHz
V
8
On-screen Display Oscillator
Frequency
Unit
Typ.
57/64

ST6391,92,93,95,97,99
EEPROM INFORMATION
The ST63xx EEPROM single poly process has been specially developed to achieve 300.000
Write/Erase cycles and a 10 years data retention.
DC ELECTRICAL CHARACTERISTICS
(TA = 0 to +70°C unless otherwise specified)
Symbol
Parameter
Test Conditions
Value
Min.
Typ.
Unit
Max.
VIL
Input Low Level Voltage
All I/O Pins
VIH
Input High Level Voltage
All I/O Pins
Hysteresis Voltage(1)
All I/O Pins
VDD = 5V
Low Level Output Voltage
DA0-DA5, PB0-PB6, OSD
Outputs, PC0-PC7,
O0, O1, PA0-PA5
VDD = 4.5V
IOL = 1.6mA
IOL = 5.0mA
0.4
1.0
V
V
Low Level Output Voltage
PA6-PA7
VDD = 4.5V
IOL= 1.6mA
IOL= 25mA
0.4
1.0
V
V
Low Level Output Voltage
OSDOSCout,
OSCout
VDD = 4.5V
IOL= 0.4mA
0.4
V
VOH
High Level Output Voltage
PB0-PB7, PA0-PA3, OSD
Outputs
VDD = 4.5V
IOH = – 1.6mA
4.1
V
V OH
High Level Output Voltage
OSDOSCout, OSCout,
VDD = 4.5V
IOH= – 0.4mA
4.1
V
IPU
Input Pull Up Current
Input Mode with Pull-up
PB0-PB6, PA0-PA3, PC0PC3
VIN= VSS
– 100
– 50
– 25
mA
IIL
IIH
Input Leakage Current
OSCin
VIN= VSS
VIN= VDD
– 10
0.1
–1
1
– 0.1
10
µA
VHYS
VOL
VOL
V OL
IIL
IIL
IIH
VDD RAM
IIL
IIH
IIL
IIH
Input Pull-down
current in Reset
Input Leakage Current
OSCIN
All I/O Input Mode
no Pull-up
OSDOSCin
VIN= VDD or VSS
RAM Retention Voltage in
RESET
0.2xV
DD
0.8xVDD
V
1.0
V
µA
100
– 10
Reset Pin with Pull-up
VIN= VSS
Input Leakage Current
AFC Pin
VIH= VDD
VIL= VSS
VIH= 12.0V
58/64

– 50
µA
10
1.5
Input Leakage Current
V
V
– 30
– 10
µA
1
µA
–1
40
ST6391,92,93,95,97,99
DC ELECTRICAL CHARACTERISTICS (Continued)
Symbol
Parameter
Test Conditions
Value
Min.
Typ.
Max.
Unit
IOH
Output Leakage Current
DA0-DA5, PA4-PA5,
PC0-PC7, O0, O1
VOH = VDD
10
µA
IOH
Output Leakage Current High
Voltage
DA0-DA5, PA4-PA7, PC4PC7, O0, O1
VOH = 12V
40
µA
IDD
Supply Current RUN Mode
fOSC= 8MHz, ILoad= 0mA
VDD= 6.0V
6
16
mA
IDD
Supply Current WAIT Mode
fOSC= 8MHz, ILoad= 0mA
VDD= 6V
3
10
mA
IDD
Supply Current at transition
to RESET
fOSC= Not App,
ILoad= 0mA
VDD= 6V
0.1
1
mA
VON
Reset Trigger Level ON
RESET Pin
VOFF
Reset Trigger Level OFF
RESET Pin
VTA
Input Level Absolute
Tolerance
A/D AFC Pin
VDD = 5V
±200
mV
VTR
Input Level Relatice
Tolerance (1)
A/D AFC Pin
Relative to other levels
VDD = 5V
±100
mV
0.3xV
DD
0.8xVDD
V
V
Note: 1. Not 100% Tested
59/64

ST6391,92,93,95,97,99
AC ELECTRICAL CHARACTERISTICS
(TA = 0 to +70°C, fOSC=8MHz, VDD=4.5 to 6.0V unless otherwise specified )
Value
Symbol
Parameter
Test Conditions
Unit
Min.
Typ.
Max.
tWRES
Minimum Pulse Width
RESET Pin
125
ns
tO HL
High to Low Transition Time
PA6, PA7
VDD = 5V, CL = 1000pF (2)
100
ns
tO HL
High to Low Transition Time
DA0-DA5, PB0-PB6, OSD
Outputs, PC0-PC7,
VDD = 5V, CL = 100pF
20
ns
tO LH
Low to High Transition Time
PB0-PB6, PA0-PA3, OSD
Outputs, PC0-PC3
VDD = 5V, CL = 100pF
20
ns
tOH
Data HOLD Time
SPI after clock goes low
I2CBUS/S-BUS Only
All devices
f DA
D/A Converter Repetition
(1)
Frequency
ST6391,92,93,99
ST6395,97
31.25
25
kHz
f SIO
SIO Baud Rate(1)
ST6391,92,93,99
ST6395,97
62.50
100
kHz
tWEE
EEPROM Write Time
TA = 25°C One Byte
5
Endurance
EEPROM WRITE/ERASE
Cycles
QA LOT
Acceptance Criteria
Retention
EEPROM Data Retention (4)
TA = 25°C
Input Capacitance (3)
All Inputs Pins
COUT
Output Capacitance (3)
All outputs Pins
COSCin,
COSCout
Oscillator Pins Internal
Capacitance(3)
COSDin,
COSDout
OSD Oscillator External
Capacitance
CIN
ns
750
300.000
10
ms
>1
million
cycles
10
years
10
pF
10
pF
5
Recommended
15
pF
25
Notes:
1. A clock other than 8 MHz will affect the frequency response of those peripherals (D/A, 62.5kHz and SPI) whose clock is
derived from the system clock.
2. The rise and fall times of PORT A have been reduced in order to avoid current spikes while maintaining a high drive capability
3. Not 100% Tested
4. Based on extrapolated data
60/64

pF
ST6391,92,93,95,97,99
PACKAGE MECHANICAL DATA
Figure 67. ST639x 42 Pin Plastic Dual-In-line Package
Dim.
mm
Min
inches
Typ
Max
A
Min
Typ
5.08
Max
0.200
A1
0.51
B
0.35
0.59
0.020
0.014
0.023
B1
0.75
1.42
0.030
0.056
C
0.20
0.36
0.008
0.014
D
36.32
39.12 1.430
1.540
D1
–
–
–
E
–
–
18.54
E1
13.72
0.540
K1
–
–
–
–
–
K2
–
–
–
–
–
L
2.54
3.81
.100
e1
–
0.730
1.78
–
–
0.150
0.070
Number of Pins
N
ORDERING INFORMATION
The following chapter deals with the procedure for
transfer the Program/Data ROM codes to SGSTHOMSON.
Communication of the ROM Codes. To communicate the contents of Program /Data ROM memories to SGS-THOMSON, the customer has to send
a 5” Diskette with:
– one file in INTEL INTELLEC 8/MDS FORMAT
for the PROGRAM Memory
– one file in INTEL INTELLEC 8/MDS FORMAT
for the ODD and EVEN ODD OSD Characters
42
– one file in INTEL INTELLEC 8/MDS FORMAT
for the EEPROM initial content
(this file is optional)
– a filled Option List form as described in the
OPTION LIST paragraph.
The program ROM should respect the ROM Memory Map as in Table 22.
The ROM code must be generated with ST6 assembler. Before programming the EPROM, the
buffer of the EPROM programmer must be filled
with FFh.
61/64

ST6391,92,93,95,97,99
Customer EEPROM Initial Contents:
Format
a. The content should be written into an INTEL
INTELLEC format file.
b. In the case of 384 bytes of EEPROM, the starting addressis 000h and the end address is 7Fh.
The order of the pages (64 bytes each) is an in
the specification (ie. b7, b1 b0: 001, 010, 011,
101, 110. 111).
c. Undefined or don’t care bytes should have the
content FFH.
OSD Test Character. IN ORDER TO ALLOW THE
TESTING OF THE ON-CHIP OSD MACROCELL
THE FOLLOWING CHARACTER MUST BE PROVIDED AT THE FIXED 3Fh (63) POSITION OF
THE SECOND OSD BANK.
Listing Generation & Verification. When SGSTHOMSON receives the files, a computer listing is
generated from them. This listing refers extractly to
the mask that will be used to produce the microcontroller. Then the listing is returned to the customer
Figure 68. OSD Test Character
that must thoroughly check, complete, sign and
return it to SGS-THOMSON. The signed list constitutes a part of the contractual agreement for the
creation of the customer mask. SGS-THOMSON
sales organization will provide detailed information
on contractual points.
Table 22. ROM Memory Map
ROM Page
Device
Address
EPROM
(1)
Address
Description
Page 0
0000h-007Fh
0080h-07FFh
0000h-007Fh
0080h-07FFh
Reserved
User ROM
Page 1
“STATIC”
0800h-0F9Fh
0FA0h-0FEFh
0FF0h-0FF7h
0FF8h-0FFBh
0FFCh-0FFDh
0FFEh-0FFFh
0800h-0F9Fh
0FA0h-0FEFh
0FF0h-0FF7h
0FF8h-0FFBh
0FFCh-0FFDh
0FFEh-0FFFh
User ROM
Reserved
Interrupt Vectors
Reserved
NMI Vector
Reset Vector
Page 2
0000h-000Fh
0010h-07FFh
1000h-100Fh
1010h-17FFh
Reserved
User ROM
PAGE 3
0000h-000Fh
0010h-07FFh
1800h-180Fh
1810h-1FFFh
Reserved
user ROM
Page 4
0000h-000Fh
0010h-07FFh
2000h-200Fh
2010h-27FFh
Reserved
User ROM
Page 5
0000h-000Fh
0010h-07FFh
2800h-280Fh
2810h-2FFFh
Reserved
User ROM
Page 6
0000h-000Fh
0010h-07FFh
3000h-300Fh
3010h-37FFh
Reserved
User ROM
Page 7
0000h-000Fh
0010h-07FFh
3800h-380Fh
3810h-3FFFh
Reserved
User ROM (End of 16K)
Page 8
0000h-000Fh
0010h-07FFh
4000h-400Fh
4010h-47FFh
Reserved
User ROM
Page 9
0000h-000Fh
0010h-07FFh
4800h-480Fh
4810h-4FFFh
Reserved
User ROM (End of 20K)
Note 1. EPROM addresses are related to the use of ST63P9X piggyback emulation devices.
62/64

ST6391,92,93,95,97,99
Customer:
Address:
Contact:
Phone No:
Reference:
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
ST639x MICROCONTROLLER OPTION LIST
. . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
Device
[ ] (d)
Package
[ ] (p)
Temperature Range
For marking one line with 10 characters maximum is possible
Special Marking [ ] (y/n)
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
[ ] (t)
Line1 “ _ _ _ _ _ _ _ _ _ _ ” (N)
Notes:
(d) 1= ST6391, 2 = ST6392, 3 = ST6393, 4 = ST6395, 5 = ST6397, 6 = ST6399
(p) B= Dual in Line Plastic
(t) 1= 0 to 70°C
(N) Letters, digits, ’
. ’, ’ - ’, ’ /
’ and spaces only
Marking: the default marking is equivalent to the sales type only (part number).
OSD POLARITY OPTIONS (Put a cross on selected item) :
POSITIVE
NEGATIVE
VSYNC,HSYNC
[ ]
[ ]
R,G,B
[ ]
[ ]
BLANK
[ ]
[ ]
CHECK LIST:
ROM CODE
OSD Code: ODD & EVEN
EEPROM Code (if Desired)
YES
[ ]
[ ]
[ ]
NO
[ ]
[ ]
[ ]
Signature ...................................
Date ...........................................
63/64

ST6391,92,93,95,97,99
ORDERING INFORMATION TABLE
Sales Type
ROM/EEPROM Size
Temperature Range
Package
ST6391B1/XX
16K/128 Bytes
0 to + 70 ° C
PSDIP42
ST6392B1/XX
20K/128 Bytes
0 to + 70 ° C
PSDIP42
ST6393B1/XX
16K/128Bytes
0 to + 70 ° C
PSDIP42
ST6395B1/XX
20K/384 Bytes
0 to + 70 ° C
PSDIP42
ST6397B1/XX
20K/384 Bytes
0 to + 70 ° C
PSDIP42
ST6399B1/XX
16K/128 Bytes
0 to + 70 ° C
PSDIP42
Note: “XX” Is the ROM code identifier that is allocated by SGS-THOMSON after receipt of all required options and the related ROM file.
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsability for the
consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No
license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specifications mentioned
in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied.
SGS-THOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without the
express written approval of SGS-THOMSON Microelectronics.
 1994 SGS-THOMSON Microelectronics - All rights reserved.
Purchase of I2C Components by SGS-THOMSON Microelectronics conveys a license under the Philips I2C Patent.
Rights to use these components in an I2C system is granted provided that the system conforms to the I2C Standard
Specification as defined by Philips.
SGS-THOMSON Microelectronics Group of Companies
Australia - Brazil - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands
Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A.
64/64
