NORD>) 0048h db 10 ; max. nbr of connections ( 10 ) 0049h db 00h ; Monitormode ( 00h ) ; Bit 0 - I-Frames ; Bit 1 - UI-Frames ; Bit 2 - Supervisory-Frames ; Bit 3 - Monitor during connect 004Ah db 1 ; Digipeat on = 1 ( 1 ) 004Bh db 32 ; P-Persistence-Value, 0..255 ( 32 ) 004Ch db 10 ; WAIT, 10ms, (Slottime) ( 10 ) 004Dh db 30 ; TXDELAY, 10ms ( 30 ) 004Eh db 03h ; Flow Control ( 03h ) ; Bit 0 - Flow Control on ; Bit 1 - XON/XOFF on 004Fh db 1 ; TX PTT, 0 suppressed ( 1 ) 0050h db 1 ; Auto-Linefeed, 1 on ( 1 ) 0051h db 1 ; Terminalecho, 1 on ( 1 ) 0052h db 2 ; MAXFRAME ( 2 ) 0053h db 10 ; RETRY ( 10 ) 0054h db 0 ; Callsign-check, 1 on ( 0 ) 0055h db 0 ; Fullduplex, 1 on ( 0 ) 0056h db 0 ; UIPOLL, 0=UI 1=UI+ ( 0 ) 0057h db 0 ; Stamp ( 0 ) ; 0 off ; 1 status-messages ; 2 " and monitorframes 0058h db 0 ; send flags in pauses, 1 on ( 0 ) 0059h dw 150 ; Timer 2, 10ms ( 150 ) 005Bh dw 18000 ; Timer 3, 10ms ( 18000 ) 005Dh db 2 ; Alpha 3 ( 2 ) 005Eh dw 500 ; Initial RTT, 10 ms ( 500 ) 0060h db 60 ; Paclen for I-POLL ( 60 ) ; New parameters for PK232/PK88 0061h dw 1200 ; Speed HF-interface ( 1200 ) 0063h dw 9600 ; Speed RS232-interface ( 9600 ) ; 300 = 012Ch ; 600 = 0258h ; 1200 = 04B0h ; 2400 = 0960h ; 4800 = 12C0h ; 9600 = 2580h ; 19200 = 4B00h (only RS232) 0065h db 3 ; Modem-mode (see @H) ( 3 ) 5. Switching to Original-Software (only PK232) In fact there is one disadvantage about the new EPROM. The Firmware only supports Packet-Radio. The other modes are not operational any longer. To be able to use the other modes it is desirable to have the original firmware available, too. One solution for this is a small circuit-board with two EPROM- sockets and a connection to the EPROM-socket of the PK232. All pins, except pin 20 (Chip-Enable) must be connected through all sockets. On both sockets a 2.2k-resistor must be connected between pin 20 and pin 28 (Vcc). Now with a switch one of the two Chip-Enable-pins (pin 20) can be connected to pin 20 of the PK232 to make the EPROM operational. One socket must contain the original firmware, the other socket the new firmware-EPROM. The switch must not be changed during operation. 6. Credits The Firmware for PK232/PK88 is a port of the TNC2-version developed by NORD>