VM 111 programmer with USB cable

[engr_joni_ee]

Hi,
Does anyone has ever tried VM 111 microcontroller programmer by Velleman with USB to UART cable ? I don't have RS 232 port in my laptop. I am trying to connect VM 111 with MCP2221 but it does not work. Any idea what I am doing wrong ?

 

[00kam]

Hello
from data sheet of MCP2221

• Enumerates as a Composite USB Device (CDC
and HID) Using Standard Drivers for Virtual Com
Port (VCP) on the Following Windows® Operating
Systems: XP® (SP3), Vista®, 7, 8, 8.1 and 10
• Configuration Utility for Establishing a Custom
just connect MCP2221 to your USB port and then go to "device manage" in you P.C to see the new device definition

kamal

 

[engr_joni_ee]

Well, it does not work and that's why I put this question here. I have tested MCP2221 adapter board having USB port and DB 9 connector. I use PuTTY in PC. I connect pin 2 and pin 3 on the DB 9 connector, it works in loop back as it appear as virtual COM but it does not work when I connect VM 111 programmer. Has anyone tried that ?

 

[00kam]

in my previous post i didn't pay attention to VM111 because you was taking about mcp2221 and PuTTY program at the end of issue you want to run your VM111 PIC programmer . why you didn't say how can i use my programmer by use USB and what use of putty here. anyhow VM111 is old type programmer supports RS232 com port only works with PC (XP opration system ) has RS232 com port .regarding with MCP2221 it is converter from UART or I2C to USB not from RS232(DB9) to USB
kamal

 

[FvM]

VM111 uses more than RS232 Rx and Tx line, and it uses the handshake lines to control the PIC ICSP signals directly, obviously not through UART serial characters.

I have seen stated in a Vellmann document that the programmer doesn't work with USB RS232 adapters. I'm not sure what's the exact reason, it may be either due to level issues or different timing of handshake signals through virtual COM port. If an USB-to-RS232 bridge should work with the programmer, it must surely provide all handshake lines of the 9-pin RS232 connector. And as mentioned by 00kam, correct RS232 level signals.

 

[engr_joni_ee]

Hi,
Can I include all handshake lines of the 9-pin RS232 connector (DB 9) using MCP 2221 ? to make it work with VM 111 programmer ?

--- Updated Jan 13, 2021 ---

VM111 uses more than RS232 Rx and Tx line, and it uses the handshake lines to control the PIC ICSP signals directly, obviously not through UART serial characters.

I have seen stated in a Vellmann document that the programmer doesn't work with USB RS232 adapters. I'm not sure what's the exact reason, it may be either due to level issues or different timing of handshake signals through virtual COM port. If an USB-to-RS232 bridge should work with the programmer, it must surely provide all handshake lines of the 9-pin RS232 connector. And as mentioned by 00kam, correct RS232 level signals.

Can I include all handshake lines of the 9-pin RS232 connector (DB 9) using MCP 2221 ? to make it work with VM 111 programmer ? If no, then would you like to suggest any solution for those who don't have DB 9 connector in their laptops ?

 

[FvM]

I'm under the impression that MCP2221 isn't designed to emulate a RS232 interface with hardware handshake lines. For simlar purposes, I'm using ready-made USB-to-RS232 adapter cables from major manufacturers, e.g. FTDI like Chipi-X https://www.ftdichip.com/Support/Documents/DataSheets/Cables/DS_Chipi-X.pdf

However, following the Vellman manual warning, I'm not sure if VM111 would work even with quality adapters.

 

[engr_joni_ee]

I just see from the schematic of k8048, they don't even use pin (2) in DB 9 connector which is bit strange. This means that the communication is not UART. Any comment here ?

I also notice that they directly access PGC signal in the programmer sockets through pin (7) of the DB 9 connector. This might be the reason that we can't use USB to Serial (RS 232) converters.

Any other solution for those who don't have RS 232 serial port on their laptops ?