I-62
EPSON
S1C88348/317/316/308 TECHNICAL HARDWARE
5 PERIPHERAL CIRCUITS AND THEIR OPERATION (Output Ports)
5.6 Output Ports (R ports)
5.6.1 Configuration of output ports
The S1C88348/317/316 is equipped with a 34-bit
output port (R00–R07, R10–R17, R20–R27, R30–R37,
R50, R51) and the S1C88308 is equipped with a 30-
bit output port (R00–R07, R10–R17, R20–R27, R30–
R34, R50).
Depending on the bus mode setting, the configura-
tion of the output ports may vary as shown in the
table below.
Table 5.6.1.1 Configuration of output ports
Only the configuration of the output ports in single
chip mode will be discussed here. With respect to
bus control, see "5.2 System Controller and Bus
Control".
Figure 5.6.1.1 shows the basic structure (excluding
special output circuits) of the output ports.
*
R35–R37 and R51 are not available in the
S1C88308.
VDD
VSS
Data
bus
Rxx
Address
Data register
Address
High impedance
control register
Mask
option
Nch open drain can be set for R00–R07 and R10–R17 by
the mask option.
VDD
VSS
Data
bus
Rxx
Address
Data register
Address
High impedance
control register
R20–R27, R30–R37, R50, R51
Fig. 5.6.1.1 Structure of output ports
In modes other than single chip mode, the data
registers and high impedance control registers of
the output ports used for bus function can be used
as general purpose registers with read/write
capabilities. This will not in any way affect bus
signal output.
Note: When the 160-pin package is selected for a
shipping form of the S1C88348/317/316, the
output port terminals R35, R36 and R37 can
not be used because these are non-bonding
terminals. However, the data registers
(R35D–R37D) and high impedance control
registers (HZR35–HZR37) corresponding to
these output ports can be used as general
purpose registers with read/write capabilities.
The output specification of each output port is as
complementary output with high impedance
control in software possible.
Besides normal DC output, output ports R25–R27,
R34, and R50 have a special output function, which
can be selected by software.
Terminal
R00
R01
R02
R03
R04
R05
R06
R07
R10
R11
R12
R13
R14
R15
R16
R17
R20
R21
R22
R23
R24
R25
R26
R27
R30
R31
R32
R33
R34
R35
R36
R37
R50
R51
Bus mode
Expanded 64K Expanded 512K
Single chip
Address A0
Address A1
Address A2
Address A3
Address A4
Address A5
Address A6
Address A7
Address A8
Address A9
Address A10
Address A11
Address A12
Address A13
Address A14
Address A15
Output port R20
Output port R21
Output port R22
Address A16
Address A17
Address A18
RD signal
WR signal
Output port R25
Output port R26
Output port R27
Output port R30/CE0 signal
Output port R31/CE1 signal
Output port R32/CE2 signal
Output port R33/CE3 signal
Output port R34
Output port R35
Output port R36
Output port R37
Output port R50
Output port R51/BACK signal
*
Output port R23
Output port R24
Output port R00
Output port R01
Output port R02
Output port R03
Output port R04
Output port R05
Output port R06
Output port R07
Output port R10
Output port R11
Output port R12
Output port R13
Output port R14
Output port R15
Output port R16
Output port R17
Output port R51
Output port R30
Output port R31
Output port R32
Output port R33