brouw@dutesta.UUCP (Gerard Brouwer) (01/28/88)
The newsgroup 'comp.sys.cbm' contains a lot of information for the
C-128 and C-64 computers. I wondered if there are also users of
different types of Commodore-computers, especially the family of
C-116, C-16, C-232 and Plus4.
I find it difficult to get detailed information about this family,
so here are my questions:
- I want to use the User-port of the Plus4 for I/O.
There are two parts:
Part 1: RS-232 interface connections.
Part 2: 8 databits and other connections.
The 8 databits are easy to program for output:
LDA <data>
STA $FD10
But what about input?
Is there a Data Direction Register (like a C-64)?
- What is the influence of the ACIA to the User-port?
The ACIA has four registers:
1 - Command register
2 - Status register
3 - Data register
4 - Error register (?)
I know these registers are used by the RS-232 routines, but I
don't know what they really do. Who can help me??
- Is there a 'Programmer's Reference Guide for the Plus4' available
just like the 'Programmer's Reference Guide for the 64'?
- Where can I get circuit-diagrams of these computers?
I would appreciate it, if someone could help me. If you have information
you can 'e-mail' it to me or post it to me by physical mail.
Thanks for your cooperation.
Gerard Brouwer
P.O.-Box 4117
3102 GC Schiedam
The Netherlands
E-mail: brouw@dutesta.UUCPeric@cbmvax.UUCP (Eric Cotton) (02/02/88)
In article <1071@dutesta.UUCP> brouw@dutesta.UUCP (Gerard Brouwer) writes: > >The newsgroup 'comp.sys.cbm' contains a lot of information for the >C-128 and C-64 computers. I wondered if there are also users of >different types of Commodore-computers, especially the family of >C-116, C-16, C-232 and Plus4. >[...] >- Is there a 'Programmer's Reference Guide for the Plus4' available > just like the 'Programmer's Reference Guide for the 64'? > >- Where can I get circuit-diagrams of these computers? Yes there is a programmmer's reference guide for the C-16 & PLUS 4. I believe it was published by Sams Books about three or four years ago. The authors were Cyndy Merten and Sarah Meyers (I'm not sure of the spelling). Whether or not it is still in print I do not know. -- Eric Cotton Commodore-Amiga *======================================================================* *===== UUCP: {rutgers|ihnp4|allegra}!cbmvax!eric =====* *===== FONE: (215) 431-9100 =====* *===== MAIL: 1200 Wilson Drive / West Chester, PA 19380 =====* *===== PAUL: "I don't find this stuff amusing anymore." =====* *======================================================================*
fred@cbmvax.UUCP (Fred Bowen) (02/02/88)
In article <1071@dutesta.UUCP>, brouw@dutesta.UUCP (Gerard Brouwer) writes: > C-116, C-16, C-232 and Plus4. > I find it difficult to get detailed information about this family, > so here are my questions: > - I want to use the User-port of the Plus4 for I/O. > The 8 databits are easy to program for output: > But what about input? > Is there a Data Direction Register (like a C-64)? The Plus/4 does not use a 6526 like the C64/128, but instead a 6529. There is no data direction register. Data is written to the port when R/W is low, and read from the port when R/W is high. Passive output pullups allow the bits to act as both outputs and inputs. > - What is the influence of the ACIA to the User-port? > The ACIA has four registers: > 1 - Command register > 2 - Status register > 3 - Data register > 4 - Error register (?) > I know these registers are used by the RS-232 routines, but I > don't know what they really do. Who can help me?? Briefly, the 6551 ACIA located at $FD00 works like this: 0 data transmit & receive data, bit-0 is leading bit. 1 status bit 0=parity, 1=frame, 2=overrun, 3=rcvr full, 4=xmit full, 5=DCD, 6=DSR, 7=IRQ. The error bits are cleared by reading status. 2 command used to control xmit/rcv functions: parity, duplex, xmit controls, rcvr IRQ, and DTR control. 3 control used to select #stop bits, word length, rcvr clock, and baud rate. The C64 manual describes these pretty well, altho there are some differences. The 6551 is a fairly standard chip, and specs should be obtainable in the Netherlands. > - Is there a 'Programmer's Reference Guide for the Plus4' available Yes, but I have not seen one personally. Howard W. Sams & Co. (SAMS) published it in the US. The info I have says they can be reached via mail at 62nd Street, Indianapolis, IN 46268 or by phone, 800-428-SAMS. This info is fairly old however... > - Where can I get circuit-diagrams of these computers? Such info is not usually available, at least not from us. Sometimes you can get it from some european centers. Since it may be of help, here's the pinout of the Plus/4 user port. Note these are TTL signals and for RS-232 require a level converter such as the 1011A (no longer available from CBM). 1 GND A GND 2 +5V B (6529 $FD10 BIT-0) 3 /RESET C RxD (6551 $FD00 recv data) 4 CSTSENSE (6529 $FD10 BIT-2) D RTS (6551 $FD00) 5 (6529 $FD10 BIT-3) E DTR (6551 $FD00) 6 (6529 $FD10 BIT-4) F (6529 $FD10 BIT-7) 7 (6529 $FD10 BIT-5) H DCD (6551 $FD00) 8 RxC (6551 $FD00 clock) J (6529 $FD10 BIT-6) 9 ATN K CTS (6529 $FD10 BIT-1) 10 9VAC L DSR (6551 $FD00) 11 9VAC M TxD (6551 $FD00 xmit data) 12 GND N GND -- -- Fred Bowen uucp: {ihnp4|rutgers|caip}!cbmvax!fred arpa: cbmvax!fred@RUTGERS.EDU tele: 215 431-9100 Commodore Electronics, Ltd., 1200 Wilson Drive, West Chester, PA, 19380