Needs some more for the read and write controls. Is the address latched from the altairmicro? if not you'll need a latch using the ALE. You need to add a read port for the various status bits. Dwight ________________________________________ From: cctalk <cctalk-bounces at classiccmp.org> on behalf of dave at 661.org <dave at 661.org> Sent: Sunday, December 13, 2015 12:02 AM To: cctalk Subject: Making a serial board for Briel Altair Micro After fiddling around with my Briel Altair Micro, I've come to desire more than just the console serial port. To that end, I read up on the 16550A UART, line drivers, line receivers, and schematics for other implementations of serial ports. I came up with this: http://661.org/tmp/altairmicro-serial.pdf How close am I to this design making sense and working? -- David Griffith dave at 661.org A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?