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371
User’s Manual U11302EJ4V0UM
CHAPTER 19
μ
PD78P0208
The
μ
PD78P0208 is a product integrating a one-time programmable ROM (one-time PROM). Table 19-
1 shows the differences between the
μ
PD78P0208 and the mask ROM versions (
μ
PD780204, 780204A,
780205, 780205A, 780206, and 780208).
Table 19-1. Differences Between
μ
PD78P0208 and Mask ROM Versions
Item
μ
PD78P0208
Mask ROM Versions
Internal ROM configuration
One-time PROM
Mask ROM
Internal ROM capacity
60 KB
μ
PD780204:
μ
PD780204A: 32 KB
μ
PD780205:
μ
PD780205A: 40 KB
μ
PD780206:
μ
PD780208:
32 KB
40 KB
48 KB
60 KB
Internal expansion RAM capacity
1024 bytes
μ
PD780204:
μ
PD780204A: None
μ
PD780205:
μ
PD780205A: None
μ
PD780206:
μ
PD780208:
None
None
1024 bytes
1024 bytes
Change in capacity of internal
ROM by means of internal memory
size switching register (IMS)
Possible
Note 1
Impossible
Internal expansion RAM size
switching register (IXS)
Provided (Internal expansion RAM
capacity can be changed using
IXS
Note 2
.)
μ
PD780204, 780204A,
μ
PD780205, 780205A: Not provided
μ
PD780206, 780208:
(However, internal expansion RAM
capacity cannot be changed.)
Provided
IC pin
None
Provided
V
PP
pin
Provided
None
P30/TO0 to P32/TO2, P33/TI1,
P34/TI2, P35/PCL, P36/BUZ, P37
On-chip pull-down resistors are not
provided.
On-chip pull-down resistors can be
specified in 1-bit units by mask option.
P70 to P74
On-chip pull-up resistors are not
provided.
On-chip pull-up resistors can be
specified in 1-bit units by mask option.
FIP0 to FIP12
On-chip pull-down resistors are
provided (connected to V
LOAD
).
On-chip pull-down resistors can be
specified in 1-bit units by mask option.
P80/FIP13 to P87/FIP20,
P90/FIP21 to P97/FIP28,
P100/FIP29 to P107/FIP36,
P110/FIP37 to P117/FIP44,
P120/FIP45 to P127/FIP52
On-chip pull-down resistors are not
provided.
On-chip pull-down resistors can be
specified in 1-bit units by mask option.
Pull-down resistors can be specified to
be connected to either V
LOAD
or V
SS
in 4-
bit units from P80.
Electrical specifications
Refer to the separate data sheet.
Notes 1.
After RESET input, the internal PROM capacity is set to 60 KB.
2.
After RESET input, the internal expansion RAM capacity is set to 1024 bytes.
Caution
There are differences in noise immunity and noise radiation between the PROM and mask ROM
versions. When pre-producing an application set with the PROM version and then mass-
producing it with the mask ROM version, be sure to conduct sufficient evaluations for the
commercial samples (not engineering samples) of the mask ROM version.