FIELD BULLETIN NUMBER 21 July 1983 TS 803: CHANGING BAUD RATE Baud rates for the serial printer port and the modem port are controlled through the timer data registers of the Z80 STI. The modem port is set with timer A of the STI at address %2A. The serial printer is on timer B at address %2B. To change the baud rates for either of these channels, write the hexadecimal byte corresponding to the required baud rate into the appropriate timer data register: Hex Byte Decimal (ref) Baud Rate 01 01 9600 02 02 4800 04 04 2400 08 08 1200 10 16 600 20 32 300 40 64 150 60 96 110 80 128 75 Baud rates for the keyboard, mouse, and TS 803 option board are fixed. TS 816/40: TRANSFER I/O PROBLEMS Transfer I/O problems are occuring on some TS 816/40 systems When this occurs, install jumpers on the main logic board as listed below. Transfer problems are associated with a TS 816/40 transfer out and a user station transfer in. An XFO error mes- sage will display on the service terminal with identification of the associated user station. This fix is only for those systems that have persistent problems, and should not be performed on un- affected systems. This is a detailed modification and should only be installed by qualified technicians using proper equip- ment. Be especially careful of static electricity damage to the logic board. PERFORM THIS MODIFICATION ONLY IF THERE ARE PER- SISTENT XFO ERRORS ASSOCIATED WITH THE SYSTEM. Device Jumper A23 Pin 31 to pins 18 and 23 A24 Pin 31 to pins 18 and 23 A36 Pin 31 to pins 18 and 23 A37 Pin 31 to pins 18 and 23 A66 Pin 31 to pins 18 and 23 A67 Pin 31 to pins 18 and 23 A81 Pin 31 to pins 18 and 23 A82 Pin 31 to pins 18 and 23