High speed serial link

[shrub3056]

Can anybody help me setup a high speed serial connection between my PC and my Amiga and visa versa. I’m using Amiga Explorer with no problem but its only 19200 baud max, I have hyper term, transdisk, transwarp, BaudBandit and quickfix and such but I haven’t got an idea how to set it up Thanks.

[Matt020]

Sure. Which model of Amiga do you have?

[shrub3056]

I have an Amiga 500+ with 2meg chip, 8meg fast and a 4GB CF drive

[Ed Cruse]

With an unaccelerated 500 you might not be able to receive reliably anything higher then 19200. I've done 28800 with a stock 1200 and it seemed to work fine but every once in awhile it would mess up. At 19200 it was very reliable.

[shrub3056]

Could you tell me Ed how you achieved 28800.

[desiv]

I didn't have much luck with 28,800 personally, but I was using a really old USB<>serial device so maybe that was my problem.
I even tried using the baudbandit.device, which you are supposed to use to get the most speed out of an A500 serial port.

desiv

[whiteb]

Originally Posted by shrub3056

Could you tell me Ed how you achieved 28800.

28800 was Easily achievable on an unaccelerated A500 using BaudBandit.device.

I once had my A500 on a 56k modem at 115200 using the device (For the Hardware data compression), but that was Pre-ADSL days.

Before that, I had a 14400 modem, set to 19200 (Again for the compression), and the A500 *NEVER* missed a beat. That A500 is actually in the cupboard right now, with 3 other of its twins.

Mind you, to sustain a *FAST* transfer, you need to send the file to a FAST device, like RAD: (Ram drive) or a HDD that can easily clear its receive buffers before the next data arrives.

And for that, you need lots of ram. (At the time, IIRC the A500 did have 4MB of ram, or it might have been when I had the A530, in which case it did have an 030/8MB Ram)..

[Jope]

IIRC back in the day I had 38400 as the data terminal speed on my A500, 14400bps modem, 512/512k. I also used baudbandit. Terminus was my terminal of choice.

Downloads to RAM:, then copied them to floppy after that.

[Ed Cruse]

Originally Posted by shrub3056

Could you tell me Ed how you achieved 28800.

I have a terminal program that will do 28800, it's one that I wrote. Running 28800 in my example above was also a program that I wrote. I'm sure there are store bought programs that will do higher then 19200.

The problem that I had with 28800 was with a serial port network that was used for network type of communications between 11 computers. Every once in awhile a bit would get lost or something and the whole system would stop working properly. At 19200 I never had problems even after 7 years of running the system.

[Leffmann]

Used to run a 28800 modem on an old A500, worked perfectly fine, though you had to set a large download buffer or it would just choke. I don't think it was possible to download to harddrive or even RAM: because even the filesystem overhead was too much. Them were the days of large phone bills! Dad was not amused.

BTW, wouldn't the parallel port be faster for data transfer since it's 8 bits wide or something?

[clauddio]

I can do 115200 on my A1200/020 28mhz on amiga explorer using normal serial.device
others serial devices doesn't works fine there
I calculate than any amiga with a cpu > 25mhz can reach max speed

all depends of the cpu power

shrub3056,

a normal A500 with a 68000 can reach 19200 as maximum and I think that there is not trick to bypass that limitation unless you purchase a turboboard

[SpeedGeek]

I use Windows HyperTerminal and Ncomm on my A3000 to transfer files at 115K baud via null modem cable. (Yes parallel port is faster but more complicated to set up). 8n1.device is only slightly faster than serial.device but anything helps. My A3000 has a 40 Mhz 040 and 3 MB/sec HD DMA and that helps also. My A3000 can send at approx. 10K CPS but only receive at about 8K CPS due to lack of buffering on serial port. But at least you have an idea of whats possible.

[shrub3056]

Good I’m now using NComm and Windows HyperTerminal I can transfer Amiga to PC though the rate is slower than Amiga Explorer (19200) I can’t transfer PC to Amiga at all. Do I need to initiate BaudBandit if so how is this done? Baud rate is at 115200 Thanks

[desiv]

Originally Posted by shrub3056

Do I need to initiate BaudBandit if so how is this done? Baud rate is at 115200 Thanks

Your Amiga software (ncomm, jrcomm, etc??) should support that in the config.
I know some do, so where you see serial.device, you change it to BaudBandit.device (assuming you also have the BaudBandit.device file in your DEVS: folder).

When I was testing with transwarp (CLI), it has an option ("transwarp -d BaudBandit.device" or something like that) to tell it to use that rather than the standard serial.device..

desiv

[SpeedGeek]

Both Hyperterminal and Ncomm need to be set to the same baud rate. Simply copy baudbandit.device to DEVS: and reconfigure Ncomm to use Baudbandit.device. I use 8n1.device because its supposed to be faster or less buggy. Zmodem is usally the fastest and most reliable Comm protocol. Finally, you should have the serial port configured for RTS/CTS on both machines.

It's a good idea to configure Ncomm to use a 4 color (colour for UK) screen to limit Chip memory DMA to a minimum. (I configured Ncomm to open a WB window on my graphics board). If you have enough RAM: or small enough files coping files to RAM: can also help.

[desiv]

Originally Posted by SpeedGeek

Finally, you should have the serial port configured for RTS/CTS on both machines.

Yep, although that can depend on the type of null modem cable you have.
Some applications will call it "hardware," which is RTS/CTS.
Try it first tho, before you fall back to Xon/Xoff or none.

Originally Posted by SpeedGeek

It's a good idea to configure Ncomm to use a 4 color (colour for UK) screen to limit Chip memory DMA to a minimum. (I configured Ncomm to open WB window on my graphics board). If you have enough RAM: or small enough files coping files to RAM: can also help.

Great points! I always forget about the 4 colors helping with serial speed!

desiv

[Jope]

Originally Posted by desiv

Great points! I always forget about the 4 colors helping with serial speed!

Terminus can go down all the way to a 1 plane screen, try to see if you can get NComm to two colours.

[clauddio]

Originally Posted by SpeedGeek

I use Windows HyperTerminal and Ncomm on my A3000 to transfer files at 115K baud via null modem cable. (Yes parallel port is faster but more complicated to set up). 8n1.device is only slightly faster than serial.device but anything helps. My A3000 has a 40 Mhz 040 and 3 MB/sec HD DMA and that helps also. My A3000 can send at approx. 10K CPS but only receive at about 8K CPS due to lack of buffering on serial port. But at least you have an idea of whats possible.

that's strange that your A3000 receive only at 8kb/sec
maybe the A1200 have a faster serial port?

I'm using serial.device from 0S3.9

my A1200 on amiga explorer can receive at exactly 10.7 kb/sec and can send at 10.2 kb/sec

for example I tested that using a photo file of 632.530 bytes and using an external clock
59 seconds to receive that file and 62 secs if I send the file to the pc

If I test large files will do idem numbers

[SpeedGeek]

Originally Posted by clauddio

that's strange that your A3000 receive only at 8kb/sec
maybe the A1200 have a faster serial port?

I'm using serial.device from 0S3.9

my A1200 on amiga explorer can receive at exactly 10.7 kb/sec and can send at 10.2 kb/sec

for example I tested that using a photo file of 632.530 bytes and using an external clock
59 seconds to receive that file and 62 secs if I send the file to the pc

If I test large files will do idem numbers

The A1200 has slightly faster Chip memory than the A3000. But I don't think thats explains everything. I've quoted the transfer rates reported by Ncomm. Hyperterminal continues to report transfer rates > 10K without factoring errors, retries, protocol overhead, and anthing else which slows the effective transfer rate. I've used OS3.9 serial.device and like I said 8n1.device is only slightly faster. But I would be interested in knowing more details about your hardware and software configuration.

[clauddio]

Originally Posted by SpeedGeek

The A1200 has slightly faster Chip memory than the A3000. But I don't think thats explains everything. I've quoted the transfer rates reported by Ncomm. Hyperterminal continues to report transfer rates > 10K without factoring errors, retries, protocol overhead, and anthing else which slows the effective transfer rate. I've used OS3.9 serial.device and like I said 8n1.device is only slightly faster. But I would be interested in knowing more details about your hardware and software configuration.

my A1200 have a 1220 turboboard 020/28mhz + 8mb ram
8m1.device works here but it is not safe like says in amiga explorer' docs....sometimes transfer corrupt files
btw,
another test I made was copy files direct to ram disk instead to hardisk...it doesn't make any difference in speed
also I changed workbench resolutions and colors from 256 to 4....also does not affect speed