Post by thread:[OT] Seeprom + VB + PC

PICsters, This isn't all that OT because the end result IS with a PIC. I'm hoping there are VB programmers out there that have tried to do this... I'm wanting to program some SEEPROMs via my printer port, but my only language is Visual Basic. I've studied Peter Anderson's code only to be left with a big "?" on my forehead. Sure, I could use someone else's code, but I want to know what's going on. Has anyone done this using VB? I know it's possible... Any info is much appreciated. Thanks in advance, Tim Hamel

I appreciate the offer...but I use VB6 and a DLL to access ports. I don't have a problem with clocking (low...high), all I have a problem with is actually sending data TO the eeprom -- shifting it, OR'ing it with a bit to keep CS high, etc. Tim Hamel In a message dated 11/20/99 2:09:26 AM Pacific Standard Time, spam_OUTDAZLOGANTakeThisOuTAOL.COM writes: > I have VBX'x that allow you to read/write to any port in the PC. > > They're for VB4 16-Bit.

<x-flowed>At 02:47 AM 11/20/99 -0500, Tim wrote: >This isn't all that OT because the end result IS with a PIC. I'm hoping there >are VB programmers out there that have tried to do this... I'm wanting to >program some SEEPROMs via my printer port, but my only language is Visual >Basic. I've studied Peter Anderson's code only to be left with a big "?" on >my forehead. Sure, I could use someone else's code, but I want to know what's >going on. Has anyone done this using VB? I know it's possible... Any info is >much appreciated. 1. WinNT will not allow you to access the parallel port. You must install a Win device driver that gives you permission. These are available on the internet. 2. In Win95 and Win98, you can access the parallel port, but VB does not have the facilities to do so. You must install a C-based DLL to give VB the capability. There are freeware DLLs of this type available on the parallel port info sits. 3. The typical parallel data port is 0x'378'. Pins 2-9 of the connector are D0 ... D7. 4. Inputs are available from the status port at 0x'379'. 5. Ground is at pin 18 of the connector. 6. I've driven a PIC 16F84 and LEDs just by plugging a few PIC input lines into the parallel port data-out lines! Apparently you can get > 10 mA per pin! ================================================================ Robert A. LaBudde, PhD, PAS, Dpl. ACAFS e-mail: .....ralKILLspam@spam@lcfltd.com Least Cost Formulations, Ltd. URL: http://lcfltd.com/ 824 Timberlake Drive Tel: 757-467-0954 Virginia Beach, VA 23464-3239 Fax: 757-467-2947 "Vere scire est per causae scire" ================================================================ </x-flowed>

I apologize for not being clearer in some areas. I have experience with the parallel port, it's just this one thing that's got me stuck. To be exact.. to read a byte from the EEPROM, the opcode is 110000000b Ok, now, I'm using Pin 2 of the parallel port (which is bit 0 of 0x378), so my question is...how do I flip that value around so it's 000000011b so that I can start outputting/shifting it? That's my exact problem right there! Much Thanks, Tim Hamel In a message dated 11/20/99 2:31:23 AM Pacific Standard Time, ralKILLspamLCFLTD.COM writes: {Quote hidden}> 1. WinNT will not allow you to access the parallel port. You must install a > Win device driver that gives you permission. These are available on the > internet. > > 2. In Win95 and Win98, you can access the parallel port, but VB does not > have the facilities to do so. You must install a C-based DLL to give VB the > capability. There are freeware DLLs of this type available on the parallel > port info sits. > > 3. The typical parallel data port is 0x'378'. Pins 2-9 of the connector are > D0 ... D7. > > 4. Inputs are available from the status port at 0x'379'. > > 5. Ground is at pin 18 of the connector. > > 6. I've driven a PIC 16F84 and LEDs just by plugging a few PIC input lines > into the parallel port data-out lines! Apparently you can get > 10 mA per > pin! >

<x-flowed>At 05:11 AM 11/20/99 -0500, Tim wrote: >I appreciate the offer...but I use VB6 and a DLL to access ports. I don't >have a problem with clocking (low...high), all I have a problem with is >actually sending data TO the eeprom -- shifting it, OR'ing it with a bit to >keep CS high, etc. > >Tim Hamel 1. VB operations: OR: iResult = iOper1 or iOper2 AND: iResult = iOper1 and iOper2 XOR: iResult = iOper1 xor iOper2 Right shift 1-bit: iResult = iOper1 \ 2 Left shift 1-bit: iResult = iOper1 * 2 E.g. iResult = (iOper and &Hf7) or &H10 2. Work on bytes individually, and use INTEGER variables (16-bit) to hold numbers. This will avoid sign extension problems. 3. Output the 16-bit integer to the port (8-bits). Only the low 8 bits will be sent. ================================================================ Robert A. LaBudde, PhD, PAS, Dpl. ACAFS e-mail: .....ralKILLspam.....lcfltd.com Least Cost Formulations, Ltd. URL: http://lcfltd.com/ 824 Timberlake Drive Tel: 757-467-0954 Virginia Beach, VA 23464-3239 Fax: 757-467-2947 "Vere scire est per causae scire" ================================================================ </x-flowed>

<x-flowed>At 05:36 AM 11/20/99 -0500, Tim wrote: >I apologize for not being clearer in some areas. I have experience with the >parallel port, it's just this one thing that's got me stuck. To be exact.. to >read a byte from the EEPROM, the opcode is 110000000b Ok, now, I'm using Pin >2 of the parallel port (which is bit 0 of 0x378), so my question is...how do >I flip that value around so it's 000000011b so that I can start >outputting/shifting it? That's my exact problem right there! Presumably you meant 1100 0000 for the value, as your's above is 9 bits. To output bit-by-bit starting with msb: iDiv=2^7 for iPos=7 to 0 step -1 iBit=iData \ iDiv 'this will be 0 or 1 for bit in position i call OutPort(&H378,iBit) iDiv=iDiv \ 2 'shift to next lowest bit next iPos ================================================================ Robert A. LaBudde, PhD, PAS, Dpl. ACAFS e-mail: EraseMEralspam_OUTTakeThisOuTlcfltd.com Least Cost Formulations, Ltd. URL: http://lcfltd.com/ 824 Timberlake Drive Tel: 757-467-0954 Virginia Beach, VA 23464-3239 Fax: 757-467-2947 "Vere scire est per causae scire" ================================================================ </x-flowed>

You are the man! =) I guess the "step -1" REALLY makes a difference. As far as the EEPROM goes, it is 9 bits (Start bit + Opcode (2 bits) + 6 bit address). Now, all I do is OR the value that goes out to 378 with 2 and CS will be high constantly. Woohoo! I thank you VERY much! Tim Hamel In a message dated 11/20/99 3:06:32 AM Pacific Standard Time, ralspam_OUTLCFLTD.COM writes: {Quote hidden}> Presumably you meant 1100 0000 for the value, as your's above is 9 bits. > > To output bit-by-bit starting with msb: > > iDiv=2^7 > for iPos=7 to 0 step -1 > iBit=iData \ iDiv 'this will be 0 or 1 for bit in position i > call OutPort(&H378,iBit) > iDiv=iDiv \ 2 'shift to next lowest bit > next iPos >