| Multicomp 6809 and the Serial Ports [message #6023] |
Wed, 27 February 2019 11:58  |
coolbear
Messages: 15
Registered: February 2019
|
Junior Member |
|
|
I recently assembled a Multicomp II board and have it configured as a 6809. My interests are with Nitros9. I'm using the first serial port as the console and right now, I'm trying to get the second serial port working as..., well as a second serial port.
First question - I see that there are three serial port device descriptors included in the Nitros9 image. Am I correct in assuming that the console is /TERM and serial B is /T0?
Second question - I'm not seeing anything coming out of the second serial port (Serial B). I see that the status register on all three ports (0xFFD0/0xFFD2/0xFFD4) is 0x02, which means that TDRE is set and I should be able to transmit. If I write a hex value to 0XFFD1, I see that character appear on the console. If I write to 0XFFD3 or 0XFFD5, I get nothing on the second serial port.
I'm wondering if that as because while there are three 6850s defined in the FPGA but perhaps the I/O from the second or third 6850 is not brought out to the connector. Clearly, one of the three is not brought out because there are only two serial presences on the PCB.
Any ideas?
|
|
|
|
RetroBrew Computers Forum
Members
Search
Help
Login
Home
