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OPERATION MANUAL
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Страница 1: ...MODEL 242 OPERATION MANUAL EO U EfliiA L ...
Страница 2: ...EL 242 MIDI INTERFACE CARTRIDGE FOR THE COMMODORE 64R OPERATION MANUAL By Stanley Jungleib and Chet Wood Sequential Sequential POSTBUS 16 3051 North First Street 3640 AA Mijdrecht San Jose CA 95134 2093 Netherlands U S A 02979 6211 408 946 5240 TELEX 12721 SQNTL NL TELEX 4997150 SEQCIR ...
Страница 3: ...THE COMMODORE 64R OPERATION MANUAL By Stanley Jungleib and Chet Wood Commodore 64 is a registered tradem ark of Commodore Business Machines Inc Manual No CM242A Issued October 1984 1984 by SEQUENTIAL CIRCUITS INC All rights reserved CM242A 2 ...
Страница 4: ...atic Diagram 9 OTHER PARTS 11 PROGRAMMING 12 INTERRUPTS 12 DRUM CLOCK INPUT OPTIONS 13 Table 1 PIA Control Modes 13 Table 2 ACIA Control Modes 13 Table 3 PIA Addressing 13 Table 4 ACIA Addressing 13 INITIALIZATION 14 TRANSMITTING MIDI DATA 14 RECEIVING MID DATA 14 READING THE FOOTSWITCH 14 READING THE DRUM CLOCK INPUT 4 BASIC PROGRAM EXAMPLE 15 PROGRAMMING IN ASSEMBLY 18 CM242A 3 ...
Страница 5: ...es depending on the application MIDI synthesizer Audio cable and sound system or headphones Applications diskette unless you plan to program the cartridge yourself Data diskette depending on the application Footswitch if desired Cable for drum machine if used This operation manual is in three sections CONNECTION AND OPERATION covers basic installation It is very short and intended for everyone HAR...
Страница 6: ...h power off to all equipment in use before connecting or disconnecting anything Otherwise serious damage may result to the C64 or cartridge MODEL 242 EOUcniidL CRCUiti snc COMMODORE 64 f iTr 1 nr V TlY V l l 1 Figure 1 CONNECTION DIAGRAM CM242A 5 ...
Страница 7: ... other functions called for by the software Use SCI s Model 839 6 Connect the external clock if desired The clock input takes a A mono phone plug Use it for synchronizing the C64 with another sequencer drum machine or clock signal recorded on tape Suppose for example that a drum machine lays down a basic rhythm on track one of a m ulti track tape recorder If the clock output of the drumbox is reco...
Страница 8: ... MIDI serial data to and from the C64 data bus The parallel interface adaptor PIA and associated circuitry route the footswitch and external clock signals to the C64 A more detailed discussion of the circuitry follows MIDI IN OPTO ISOLATOR BUFFER D START STOP IN DRUM CLOCK IN SIGNAL CONDITIONER SIGNAL CONDITIONER PIA ACIA C 64 DATA BUS CLK Figure 2 BLOCK DIAGRAM CM242A 7 MIDI OUT ...
Страница 9: ...k input signal to provide a logic signal for the PIA Since the LM311 must operate on supplies of 0 and 5V a bias network shifts the input signal so that it is centered between the supplies and a com parator reference voltage is provided of the same value The 2 5 V bias is generated by voltage divider R112 R105 filtered by C101 and added to both the signal path through R106 and to the com parator r...
Страница 10: ... Rl 14 UlOG J 101 J4 REL PER ECO O I20 DesCR f rio s i bs DO NOT SCAlE ORAWin6 13l O U E r iu A L C R O J i a if K 3051 N FIRST ST SAN JOSE CA 95134 TITLE SCME NV VT C D IA G R A M C G 4 SIZE DRAWING NO D S D 2 4 2 1 n____Ul SHEET 1 OF ...
Страница 11: ...Buffer 1 104 74LS08 Quad AND Gate Buffers the outDut of com parator U102 and applies it to U 106 40 ACIA 1 066 68A50 ACIA Motorola only Transfers data bidirectionally between the parallel C64 data bus and the serial MIDI The data bus is connected to pins 15 22 of U105 Since chip selects CS0 pin 8 and CS1 pin 10 are tied high active the C64 communicates by pulling down CS2 pin 9 through decoded chi...
Страница 12: ...nd inverted clock signal from the drumbox comes in CA1 pin 40 from U104 11 If so programmed the PIA will interrupt the C64 on the specified transition of the clock input by pulling down IRQ A pin 38 connected to the non maskable interrupt input NMI of the C64 The clock transition also sets a bit in an internal PIA register which can be polled by the C64 if interrupts are not enabled The Start Stop...
Страница 13: ...never if you re not too concerned with transm it speed to see if it is ready to send another byte The ACIA interrupt is tied to the maskable interrupt of the C64 It is beyond the scope of this manual to describe C64 interrupt handling in detail but suffice it to say that the ACIA handler must check bits 0 and 1 to determine whether the receiver or transm itter is interrupting see next page If both...
Страница 14: ...CLOCK INPUT Transition Interrupts Positive Disabled Positive Enabled Negative Disabled Negative Enabled Mode 4 5 6 7 Table 2 ACIA CONTROL MODES Interrupts Receive Transmit Disabled Enabled Disabled Enabled Disabled Disabled Enabled Enabled Mode Decimal Hexadecimal 21 149 53 181 15 95 35 B5 Table 3 PIA ADDRESSING Register Clear A Control A Control A Clear B Control B Control B Read or Write Decimal...
Страница 15: ...t check the ACIA s Status Register to see that a byte has been fully read in If ready bit 0 will be high When the ACIA is ready check bits 6 5 and 4 of the Status Register A high bit indicates the following error Bit 6 Parity error Bit 5 Overrun error Bit 4 Framing error Then read the Receive Data Register If an error was detected the data is not valid but the read must be done to reset the Status...
Страница 16: ... RECEIVE DATA REGISTER 130 REM PIA CONSTANTS 140 RA 57088 REM CLEAR RESET A REGISTER 150 CA RA 1 REM CONTROL REGISTER A 160 RB RA 2 REM CLEAR RESET B REGISTER 170 CB RA 3 REM CONTROL REGISTER B 180 MD 4 190 REM POSITIVE CLOCK TRANSITION AND NO INTERRUPTS FOR BOTH A AND B 200 REM INITIALIZE PIA 210 POKE CA MD POKE CB MD 220 REM INITIALIZE ACIA 230 POKE CR 3 REM MASTER RESET 240 POKE CR 21 REM SETUP...
Страница 17: ...BER AGAIN TRANSMIT READY ZERO VELOCITY FOR NOTE OFF 500 REM NOW A SIMILAR DOWNWARD GLISS 510 DD DELAY 520 FOR NN LO 36 TO LO STEP 1 530 WAIT SR WOK REM 540 POKE DW NN REM 550 WAIT SR WOK REM 560 POKE DW 64 REM NOTE ON 570 GOSUB 1000 REM 580 WAIT SR WOK REM 590 POKE DW NN REM 600 WAIT SR WOK REM 610 POKE DW 0 REM 620 NEXT 630 PRINT THANK YOU TRANSMIT READY SEND OUT NOTE NUMBER TRANSMIT READY NON ZE...
Страница 18: ... DELAY WHICH IS SMALLER EACH TIME IT IS CALLED 999 REM UNLESS THE DD VARIABLE IS RESET EXTERNALLY 1000 FOR N INT DD TO 0 STEP 1 1010 NEXT 1020 DD DD 2 4 1 6 1030 RETURN 1040 END 1990 REM SUBROUTINE TEST 242 MIDI HARDWARE 2000 PRINT IF TEST NOT DONE IN 8 SECONDS 2001 PRINT HIT RUN STOP RESTORE TO STOP PROGRAM 2002 PRINT THEN CHECK THE MIDI CABLE 2003 PRINT PRINT 2005 FOR A 0 TO 255 2010 WAIT SR WOK...
Страница 19: ... flag Loop until empty Load in byte to send Send MIDI OUT 3 To receive MIDI IN LOOP LDA DE02 LSR BCC LOOP LDA DE03 Read ACIA status register Check receive full flag Loop until ready Read MIDI IN k To initialize the PIA LDA MODE STA DF01 STA DF03 Use control registers to set up operating mode Obtain mode from Table 1 5 To read drum clock input LDA DF01 BPL EXIT LDA DF00 Read control register 8ranch...
