Arcnet interface

• developed from the Ameristar Arcnet Controller
• Arcnet networking system – old, slow but cheap and reliable, useful for small LANs and simple network sharing
• Arcnet requires RG62 coaxial cable instead of the RG58 used on Ethernet systems
• uses 93 ohm terminators opposed to the 50 ohm used by Ethernet
• the Arcnet interface hybrid chip comes in two different versions, HCY 9058 for bus networks and HCY 9068 for star networks
  • the manual says the card uses a bus network layout with up to 256 nodes but many A2060s has 9068 hybrids for a star network layout allowing only four cards to be connected together
  • to solve this the HCY 9068 can be simply replaced with a HCY 9058 chip
• interrupt driven (polled I/O) – one interrupt on the Amiga yields into a busy system
• to reduce traffic the driver uses the Arcnet hardware’s four buffer as a single FIFO buffer
• the badly written driver (a2060.device) has some bugs in the FIFO buffer which results in lost packets and packet collisions – increased traffic on the Arcnet bus
• manual says 2.5 Mbit/s (300 kB/s) transfer speed but only max 100 kB/s is achievable
• socket for optional network autoboot ROM
• bus activity LED connector
• supported by NetBSD and OpenBSD

recapped with Rubycon brand 105° type

original ROM