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μPD555 (μCOM-42 EVACHIP) - NEC
NEC μCOM-42 EVACHIP | |
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Manufacturer | NEC |
Model Number | μCOM-42 EVACHIP |
Part Number | μPD555 |
Introduction | 1977 (launch) |
General information | |
Family | μCOM-42 |
Clock | 100 kHz-200 kHz |
Microarchitecture | |
Microarchitecture | μCOM-42 |
Technology | pMOS |
Word size | 4 bit 0.5 octets
1 nibbles |
Electrical | |
Op. Temp | -10 °C – 70 °C |
Supply VDD | -10 V |
Supply VSS | 0 V |
Memory | |
RAM | 48 B 4.8e-5 MB (96x4 bit)
0.048 kB 384 b 4.8e-8 GB |
Max Addressable Memory | 2.4 kB |
Stack | 4 levels |
Pins | |
Pins | 64 |
IRQ lines | 2 |
I/O ports | 1 |
Input ports | 1 |
Output ports | 12 |
Packaging | |
Package | DIP64 (DIP), CerDIP64 (CerDIP) |
The μPD555 or μCOM-42 EVACHIP is a 4-bit evaluation/development microcontroller used for both software and hardware debugging of the μPD548 microcontroller.
The 555 is functionally identical to the μPD548 without the internal memory, which instead is needed to be supplied externally and connected via the additional pins. This chip also has a HOLD operation that allows step-by-step inspection of operations.
Contents
Design
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Instruction Set
- Main article: μCOM-42 ISA
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Documents
See also
Facts about "μPD555 (μCOM-42 EVACHIP) - NEC"
family | μCOM-42 + |
first launched | 1977 + |
full page name | nec/μcom-42/μpd555 + |
instance of | microcontroller + |
manufacturer | NEC + |
max operating temperature | 70 °C + |
microarchitecture | μCOM-42 + |
min operating temperature | -10 °C + |
model number | μCOM-42 EVACHIP + |
name | NEC μCOM-42 EVACHIP + |
package | DIP64 + and CerDIP64 + |
part number | μPD555 + |
pin count | 64 + |
ram | 4.8e-5 MB (0.048 kB, 48 B, 384 b, 4.8e-8 GB) + |
ram breakdown | 96x4 bit + |
technology | pMOS + |
word size | 4 bit (0.5 octets, 1 nibbles) + |