My system consists of the Z80 board version 2 with the latest monitor program (version 5.02?). I have the 4Meg RAM board and the dual IDE CF board. I am using the Propeller I/O for the console. The operating system is CPM3 banked. I am using all boards that you designed? I am also using an active terminated bus.
Part of my problem with the serial I/O board is the MAX232 chips. I am using the MAX232N with 1uF electrolytic caps. I bought 4 chips and 2 of them were dead! The other two seem to be heating up over time. When I first turn on the computer the serial board works fine, but after about 15 minutes I can't get reliable transmission. I have used the max232 chip once before on a heathkit project and as I remember I had some problems also. Do you have any advice?
Also I plan to use the serial board with xmodem to transfer programs between the Z80 and my PC. Your monitor program does not have an option to change the serial baud rate. The only way to change the baud rate is to run MYIO from CP/M. When I run MYIO and change the baud rate I don't know how to exit CP/M and get back to your monitor program without a reset which causes the serial board to reinitialize to 38400. I guess I don't understand some of the options.
Thanks for the help
Harold
On Tuesday, September 15, 2015 at 6:04:15 PM UTC-4, hlr...@gmail.com wrote:
Hi everyone.
I am building the serial I/O board - version 2(?). This board has three parts - voice synthesizer, DLP USB adaptor, and Z85C80 CSS UART. I have just finished building the serial I/O part using the Z85C80 and I haven't been able to get it to function. I know that these boards are out there so I am hoping that I can get some advice on setting up the UART. I am using only Serial port A and connecting it to a terminal emulator on my PC (TeraTerm). My basic s100 system is the Z80 board, 4M RAM board, and the propeller I/O. With the serial I/O board on the buss I am able to boot fine and I can evaluate the serial I/O board as explained in the s100computers documentation. However, I get nothing out of the serial port.
I have attached a picture of my board.
Any ideas would be great.