U880D

The U880 is an unlicensed clone of the Zilog Z80 8-bit microprocessor manufactured since 1980 by VEB Mikroelektronik "Karl Marx" Erfurt (abbreviated as MME; part of Kombinat Mikroelektronik Erfurt) in the German Democratic Republic.

The U880D supports undocumented opcodes and errors, except for very minor differences such as not setting the CARRY flag for the OUTI instruction (when L goes to zero).

Variants

• UD880D, UB880D S1: frequency 1 MHz, temperature range 0-40 °C
• U880D, UB880D: frequency 2.5 MHz (e.g. in Didaktik Gama was overclocked to 3.5 MHz), temperature range 0-70 °C
• 80-CPU: frequency 2.5 MHz, temperature range 0-70 °C, inch pitch 2.54mm for export
• VB880D: frequency 2.5 MHz, temperature range −25 - +85 °C
• UA880D: frequency 4 MHz, temperature range 0-70 °C
• 80A-CPU: frequency 4 MHz, temperature range 0-70 °C, inch pitch 2.54 mm for export
• U880DC08, Thesys Z80H: frequency 8 MHz, temperature range 0-70 °C

According to the datasheet, circuits with a frequency of 2.5 MHz and a temperature range of 0-70 °C have the designation UB 88x D (e.g. UB880D, UB855D, ...), with a frequency of 2.5 MHz and a temperature range of -25-85 °C they have designation VB 88x D, and with a frequency of 4 MHz and a temperature range of 0-70 °C have the designation UA ​​88x D

Soviet production from designs U880

The marking on the die "U880/x" suggests that the processors were probably made from a set of masks received from VEB.

• T34VM1 (in alphabet T34BM1) corresponds to U880/5. Manufactured in the Soviet Union / Russia by Angstrom since 1991 and probably beyond. Matrix size 4513x4251 µm.
• KR1858VM1 (in alphabet КР1858ВМ1) corresponds to U880/6. Compared to the T34VM1, the size of the matrix is ​​reduced by about 1.6x, there is a redesigned IO. Matrix size 3601x3409 µm.
• KR1858VM2 (in alphabet КР1858ВМ2)
• KR1858VM3 (in alphabet КР1858ВМ3) is 2µm CMOS. But thanks to the "relaxed" layout (except for the internal lower logic density in CMOS), the die size is even larger than the 4µm NMOS variant of the KR1858VM1. The matrix size is 5050x4657 µm.

More Z80 clones in RVHP

Date

Chips made in the GDR have a 2-character date code:

References

• https://en.wikipedia.org/wiki/U880 (WebArchive)
• https://zeptobars.com/en/read/t34vm1-z80-angstrem-mme (WebArchive)
• https://zeptobars.com/en/read/z80-cmos-KR1858VM3-transistor-integral-belarus (WebArchive)
• https://zeptobars.com/en/read/KR1858VM1-Z80-MME-Angstrem (WebArchive)
• https://www.kutilovo.cz/vincom/sheets/102008.pdf (WebArchive)
• https://www.shotech.de/Datasheet/RFT/U880_azb.pdf (WebArchive)
• https://www.cpu-collection.de/?l0=co&l1=Eastern%20Bloc&l2=Z80 (WebArchive)