Accelerometer | ADC | ADXL | Adxl20 | AVR | BasicStamp | BX-35 | BX28 | BX35 | COM3 | Compiler | Downloader | EEPROM | Electromagnet | GetADC | GP2D1 | GPS | I2C | IDE | Keypad | LCD | LCD+ | MIDI | Motors | Multitasking | Netmedia | Networking | PCB | PID | PlaySound | PWM | Relays | RTC | Servo | ShiftOut | SitePlayer | SPI | Stack | Timer | USB

but I'm enjoying all the fine contributions by other BX-24 users. I'm new to the BX-24 but it's working great for my application for a telescope drive interface and control system. I'm using the BX-24 to interpret the Meade LX-200 command set from a PC, drive the RA and Dec axis on a custom made mount, read the encoders, calculate and execute the PID, drive an LCD and read a keypad. This program uses 2 tasks and other timed execution subs and is working perfectly at this point. It's about 18kb loaded and 230 bytes of RAM so far. I'm amazed at the capabilities of this little computer. As a contribution to this group I want to share my encoder system with you. I'm using a 512 count quadrature encoder on each motor shaft. They turn only at about 200 rpm max in this application. To read the encoders I'm using the circuit board from an All Electronics MSE-3 mouse. This particular mouse circuit is a single chip interface with PC and Mouse Systems output. I cut out the optical sensors and wired in the TTL output from the encoders (you have to experiment with which sensor goes to which connection). The easy thing is the output. There are four wires for the RS-232 and the MSE- 3 gets it's output signal voltages from the RX input. From the DB-9 connector simply use lines: 2 TTL output, 3 +5v, 5 +5v and 7 gnd. The output line hangs a bit above ground so I double buffered the output through 2 gates on a 7404 and I get 0 and +5 v signals out. I then connect this signal to an input pin for Com3 on the Bx-24 and I get a 1200 baud serial signal in either PC or Mouse Systems format. I use the Mouse Systems format as it doesn't miss any data up to around 200 - 300 rpm. I use a constantly running task reading Com3 and updating Long counters whenever the mouse sends the 5 bytes of data which is basically constant as the motors turn. Additionally I've encountered the infamous 'EEPROM Verify Error'. After putting up with this for a few weeks I finally put the scope on the Com1 data pins and noticed that the TX line output was only 0 to 5 volts, not regular RS-232. (I seem to recall reading that this is the case somewhere.) I wired up a MAX232 to drive the TX line to true RS-232 and I now NO LONGER get any 'EEPROM verify error'. So it seems to be simply that my PC interface card just cannot reliably read the TTL level signal during the verify step (Chris commented to me that this is the stage that the error probably occured). Thanks for having this informative group... Roadz.

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From: "CountryRoadz" <> > [...] > I wired up a MAX232 to drive the TX line to true > RS-232 and I now NO LONGER get any 'EEPROM verify > error'. So it seems to be simply that my PC > interface card just cannot reliably read the TTL > level signal during the verify step [...] What type of interface card are you using? -- Frank Manning -- NetMedia, Inc.

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Frank. I used 2 serial ports. One was the on-board port of my motherboard (I don't remember the brand but it's an old AMD 366mHz K- 7). Second was another unidentified PCI board I pulled out of another old P-II 200 machine. I don't remember seeing any 'brand name' on the card. I've use this card routinely but only at 9600 and 19200 baud. So both may just be having problems at 115200. I know that according to the RS-232 specs that 0 and +5 should work. I did try 2 different short (6' length) serial cables as well. I don't have a 'newer' computer available to set up in my workshop but I'd suspect that a 'state of the art' system wouldn't see this problem. Not a problem however, just an annoyance that is now gone. Another 25 or so downloads with no EEPROM error still. Thanks for checking... Roadz. --- In basicx@y..., "Frank Manning" <fmanning@n...> wrote: > From: "CountryRoadz" <jandll@m...> > > > [...] > > I wired up a MAX232 to drive the TX line to true > > RS-232 and I now NO LONGER get any 'EEPROM verify > > error'. So it seems to be simply that my PC > > interface card just cannot reliably read the TTL > > level signal during the verify step [...] > > What type of interface card are you using? > > -- Frank Manning > -- NetMedia, Inc.

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