Specifications

Commands - 116
The SYS(6) and SYS(7) will return 0 if no error has occurred. Any nonzero value means an error
has occurred and you can request the host to retransmit the data.
The advanced user may want to know which of the three errors has occurred. The SYS function will
return 64 for an overrun error, 32 for a parity error, and 16 for a framing error. Keep in mind that
an incorrect baud rate could cause any one of these errors, since the incoming bits would be out of
time synchronization with the UART clock.
Errors are most likely to occur from noise when using modems or radio links.
SYS(8) returns the start of the keypad string table. Keys may be redefined by POKEing into the
address corresponding to the key's new value. The following routine prints the address of the keypad
string and the “key” values.
10 FOR N = SYS(8) TO SYS(8)+15
20 A = PEEK(N)
30 PRINT N,A,CHR$(A)
40 NEXT
SYS(9) and SYS(10) return the number of characters in the COM1 port input buffer and the COM2
port input buffer.
SYS(11) and SYS(12) return the COM1 port buffer full flag and the COM2 port buffer full flag.
“0” means the buffer is not full; “1” means the buffer is full.
SYS(13) and SYS(14) display the cursor position of the LCD display.
ERROR: <Data negative> – for n
<Illegal argument> – if n > number of functions