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author | AJR <ajrhacker@users.noreply.github.com> | 2019-03-23 01:28:59 -0400 |
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committer | AJR <ajrhacker@users.noreply.github.com> | 2019-03-23 01:28:59 -0400 |
commit | df939e0afb7ba1646fabe3446c358f182f3b2a2a (patch) | |
tree | f5c854e8b84593c25144c4dcf5aab4305752e552 | |
parent | 5f7021ed8c0fc37ef3f7bee62cd1c9b3e90a52c6 (diff) |
aha174x.cpp: Improve notes (nw)
-rw-r--r-- | src/devices/bus/isa/aha174x.cpp | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/src/devices/bus/isa/aha174x.cpp b/src/devices/bus/isa/aha174x.cpp index 9453f6a1856..b82888ca73f 100644 --- a/src/devices/bus/isa/aha174x.cpp +++ b/src/devices/bus/isa/aha174x.cpp @@ -7,11 +7,14 @@ These are actually EISA cards, though they also have a compatibility mode that provides an interface like the older ISA AHA-154X series. - The HPC microcode is copied to and then executed out of RAM, allowing - it to be reprogrammed by the host. - - The AHA-1740 and AHA-1740A have different board layouts and require - different microcode, though they share the following ICs: + On the AHA-1740 and AHA-1744, the HPC microcode is stored in an EEPROM + (of unknown type), allowing it to be reprogrammed by the host. This is + not possible on the AHA-1740A and AHA-1744A, which use a conventional + 27C256 EPROM for the microcode. In both cases the HPC copies the code + to and then executes it out of RAM. + + Though the AHA-1740 and AHA-1740A have different board layouts, they + share the following ICs: AIC-565 Bus Auxiliary Interface Chip AIC-575 EISA Configuration Chip |