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AMD LANCE Am7990
The Am7990 is an Ethernet media access controller (MAC) controller introduced in 1985. LANCE, short for "local area network controller for Ethernet", is also the brand name for follow-up versions of the chip. Its architecture is the basis for AMD's PCnet family of highly integrated single-chip Ethernet controllers, which succeeded the LANCE family. The one exception is the Am79C940 MAC. The Am7990 chip was fabricated in NMOS technology and has no integrated Manchester encoder/decoder (ENDEC) nor does it have an integrated 10BASE-T transceiver.
A later re-fabricated chip called the C-LANCE Am79C90 is made with 0.8 micrometre CMOS technology. The original NMOS version Am7990 and the CMOS Am79C90 version differ in some details which may affect device driver compatibility.[citation needed]
The datasheet for the CMOS version states that the CMOS and NMOS versions are the same. But the "Table B-1. Comparison Summary of the C-LANCE and LANCE Devices" in the datasheet shows they differ. These differences are not likely to require modifications of any device driver.
The PCnet family of Ethernet controllers (PCnet-ISA II, PCnet-32, PCnet-PCI II and PCnet-FAST) is LANCE software compatible. This means you should be able use the original 16-bit software on these members of the PCnet family of single-chip Ethernet controllers.
The Am7990 can handle 10 megabit/s Ethernet with back-to-back packet reception with as little as 0.5 μs interframe spacing. DMA/Bus mastering 24-bit (16M) address capable. Up to 128 ring buffers can be used. 48 byte receive/transmit FIFO. Operates with 5 volt DC 5% supply and logic. Features a Time-domain reflectometer (TDR) with a granularity of 30 meter. 16.8 MHz maximum frequency.
Physically a DIP-48 or PLCC-68 package is used. CSR0 slave read data can cause timing violations on DAL lines.
The Am7990 handles a decoded and clock-recovered Ethernet bitstream complete with a collision-detection flag. Specifically, the Am7990 contains neither the Manchester encoder/decoder and associated PLL nor the necessary PECL line drivers/receivers to drive the AUI interface. These functions are typically handled by the companion Am7992 "Serial Interface Adapter" chip manufactured in a bipolar process.
The AUI interface can then be connected to any AUI-compatible transceiver, which AMD (among other manufacturers) produced as well, e.g. the Am7996 transceivers for 10BASE5 and 10BASE2 networks. With the advent of twisted-pair Ethernet, 10BASE-T transceivers like the Am79C98 and Am79C100 were introduced.
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AMD LANCE Am7990 AI simulator
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AMD LANCE Am7990
The Am7990 is an Ethernet media access controller (MAC) controller introduced in 1985. LANCE, short for "local area network controller for Ethernet", is also the brand name for follow-up versions of the chip. Its architecture is the basis for AMD's PCnet family of highly integrated single-chip Ethernet controllers, which succeeded the LANCE family. The one exception is the Am79C940 MAC. The Am7990 chip was fabricated in NMOS technology and has no integrated Manchester encoder/decoder (ENDEC) nor does it have an integrated 10BASE-T transceiver.
A later re-fabricated chip called the C-LANCE Am79C90 is made with 0.8 micrometre CMOS technology. The original NMOS version Am7990 and the CMOS Am79C90 version differ in some details which may affect device driver compatibility.[citation needed]
The datasheet for the CMOS version states that the CMOS and NMOS versions are the same. But the "Table B-1. Comparison Summary of the C-LANCE and LANCE Devices" in the datasheet shows they differ. These differences are not likely to require modifications of any device driver.
The PCnet family of Ethernet controllers (PCnet-ISA II, PCnet-32, PCnet-PCI II and PCnet-FAST) is LANCE software compatible. This means you should be able use the original 16-bit software on these members of the PCnet family of single-chip Ethernet controllers.
The Am7990 can handle 10 megabit/s Ethernet with back-to-back packet reception with as little as 0.5 μs interframe spacing. DMA/Bus mastering 24-bit (16M) address capable. Up to 128 ring buffers can be used. 48 byte receive/transmit FIFO. Operates with 5 volt DC 5% supply and logic. Features a Time-domain reflectometer (TDR) with a granularity of 30 meter. 16.8 MHz maximum frequency.
Physically a DIP-48 or PLCC-68 package is used. CSR0 slave read data can cause timing violations on DAL lines.
The Am7990 handles a decoded and clock-recovered Ethernet bitstream complete with a collision-detection flag. Specifically, the Am7990 contains neither the Manchester encoder/decoder and associated PLL nor the necessary PECL line drivers/receivers to drive the AUI interface. These functions are typically handled by the companion Am7992 "Serial Interface Adapter" chip manufactured in a bipolar process.
The AUI interface can then be connected to any AUI-compatible transceiver, which AMD (among other manufacturers) produced as well, e.g. the Am7996 transceivers for 10BASE5 and 10BASE2 networks. With the advent of twisted-pair Ethernet, 10BASE-T transceivers like the Am79C98 and Am79C100 were introduced.