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EPSON
S1C8F360 TECHNICAL MANUAL
6 PROM PROGRAMMER AND OPERATING MODES
6.2 Operating Modes
Three operating modes are available in the
S1C8F360: one is for normal operation and the
others are for programming.
1) Normal operation mode
2) PROM serial programming mode
3) PROM parallel programming mode
_________
The operating mode is decided by the SPRG
terminal setting at power on or initial reset.
6.2.1 Normal operation mode
In this mode, the S1C88 core CPU and the
peripheral circuits operate by the programmed
PROM. The CPU can enter this mode after the
PROM programming has finished.
Inspection data is written to the PROM at ship-
ment. Therefore, the IC will not work even if the
normal operation mode is set before programming.
In the normal operation mode, set the terminals for
the PROM programmer as below. The board must
be designed so that the terminal settings cannot be
changed.
_________
SPRG:
Fix at a High level.
RXD, CLKW:
Open or fix at a High level.
TXD, SCLK:
Open.
6 PROM PROGRAMMER
AND OPERATING MODES
The biggest difference between the S1C8F360 and the S1C88xxx is that the S1C8F360 contains Flash
EEPROM as the ROM that allows the user to write data to it using the exclusive PROM writer.
The S1C8F360 also has a built-in PROM programmer that controls writing data to the PROM.
The following explains the PROM programmer and the operating modes that are added for the
programming operation.
6.1 Configuration of
PROM Programmer
Figure 6.1.1 shows the configuration of the PROM
programmer.
The PROM programmer supports Serial
Programming for writing data received in serial
transfer and parallel programming that uses a
parallel transfer. The programming method will be
described later.
<Terminals>
The PROM programmer uses the following input/
output terminals. The following sections will
explain handling the terminals in each operating
mode.
_________
SPRG: PROM serial programming mode setting
terminal
RXD:
Serial data receive terminal
TXD:
Serial data transmit terminal
SCLK: Serial clock input/output terminal
CLKW: Serial programming source clock (3.072
MHz) input terminal
The parallel programming mode uses other
terminals in addition to the terminals above.
However, it is not necessary to switch the lines on
the board, because the IC is programed by directly
installing it to the exclusive PROM writer.
Fig. 6.1.1 Configuration of RROM programmer
Serial transfer
controller
PROM
Programming
control circuit
Parallel transfer
controller
RXD
TXD
SCLK
Address signal
Data signal
Control signal
SPRG
CLKW
PROM programmer
Sub-address bus
Sub-data bus
From/to
exclusive
PROM writer