┌──────────────────────────────────────────────────────────┐ │ #### ### ### # # #### ##### ### │▓ │ # # # # # # # # # # # # │▓ │ # # # # #### #### ### # #### │▓ │ # # # # # # # # # # # # │▓ │ # # # # # # # # #### # # # │▓ │ │▓ │ # # #### ### #### ## ### # # ### │▓ │ # # # # # # # # # # # # # # # │▓ │ # # # ### # # ### # ### ## #### │▓ │ # # # # # # # # # # # # # # # │▓ │ ##### #### # # #### ## # # # # # # │▓ └─────────────────────────────────── ───────────────────────┘▓ ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓ ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓ RS-232 INTERFACE FOR SPECTRUM COMPUTERS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ (c) KOHASOFT'1991 (c) UАЗPRQ'1992 ending Interface functionality can be checked from the terminal program itself when connecting to each other pins TxD-RxD. In this case, the display should show stable echo of characters entered from the terminal. If the setting BBS1 is produced at 8-bit, then you need to check all modes terminal: RUS, LAT, ALTER. In alternative encoding mode IBM standard there should be no failures or incorrectly received characters, if this is observed, then you should try replacing KPS8OBB51 or reduce the baud rate. In the complete absence of echo on the screen, as well as incomplete functionality of the interface should check ZX-SPECTRUM, for example like this: 1) First of all it is necessarymake sure that no one is using There are no “conflicts” with other ports in the RS-232 address input/output (of course without connecting RS-232 to the data bus). For example, with the following BASIC program: 10 READ PORT 20 CLS : PRINT " Checking port=";PORT;" to input" 30 FOR I=0 TO 20 40 PRINT IN PORT 50 NEXT I 60 PRINT "Press any key to check next port" 70 GOTO 10 80 DATA 247,215,183,151,239,207 When checking on all ports, it should be read and printed on screen value 255 (#FF). Unfortunately, this is how you can check only input ports, although output port states in this case are not so important, nevertheless they are checked by programs means is not possible here. If there are concerns in undesirable effects on the SD or still the byte is not checked equals 255, you need to monitor the CS inputs with an oscilloscope or EO of the remaining I/O ports of the computer (line 40 for output change: 40 OUT PORT) while the program is running. Activation of these inputs will indicate that The decoder of these devices does not work correctly. 2) By connecting the RS-232 interface to the system bus and by initializing the terminal program (Term91v2)necessary make sure that the KPS8OVI5Z timer is configured in the DPKD mode to desired division factor: pulse frequency at output OUTO equal to Fclk(2000000 Hz)/K division (or Baud Rate*16). For 1200 baud, you can observe pulses with a frequency of 19200 Hz (period 52 ns) and duration 1/2000000 (0.5 ns). In the absence division, you should check all signals at the timer input and try reducing the supply voltage (see above). 3) The KPS8OBB51(A) transceiver usually works normally when given clock frequency in the absence of installation errors. When entering the exchange mode in the program: ON-LINE, should not light up the inscription ERROR in the upper right corner of the status line "Term91v2", even if no device is connected to RS-232. On exits TxD, DTR should be at log level."1"; on RTS - log."0". At the corresponding receiving inputs - active state RxD, DSR, CTS interface - log "0" (with peripherals disabled). A different state of the m/circuit pins indicates its inoperability at the moment, or a buffer malfunction K561PUCH. In ON-LINE mode, when you press the output keys TxD must be observed stable parcels transmitted symbols with a period equal to the exchange rate, and the output is RTS periodic appearance of log "1" when the receiving buffer is full BBS1 (ifpins RxD-TxD and 'echo' is displayed on the terminal screen). Unfortunately the program does not control the DTR output properly, so using it in the full RS-232 exchange protocol it is difficult. This error may be eliminated by software adjustments if such a need will arise for the user. If all checks are successful, you can test interface already with a real device, for example with a controller packet communication TNC-2. In this case, it is first necessary configure the interface for 8-bit exchange (using the SU program command (Set Universal) 8-bit,1-stop bit,no parity. It should be remembered that Usually all versions of TNC controllers are installed when turned on the default settings are different, so switching to ON-LINE mode You should first issue direct commands: 8 YAW 8 Something like the following message should appear on the terminal: nations (depending on the software version): |A PacComm TINY-2 Packet Controller AX.25 Level 2 Version 2.0 Features: KISS PERSONAL MESSAGE SYSTEM V 3.0 CLOCK CHIP SUPPORT CWID Release E1.1.6D1 May24, 1990 - 32K RAM Checksum $43 cmd: Because Usually the 'echo' mode (ECHO) is always on, you will see put on the terminal everything that is typed from the keyboard. It should also once again make sure the reliability of the transmitted and received data in RUSS, LAT, ALTER modes.PAR 0 RESTART
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