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diff --git a/Documentation/s390/3270.rst b/Documentation/s390/3270.rst new file mode 100644 index 000000000..e09e77954 --- /dev/null +++ b/Documentation/s390/3270.rst @@ -0,0 +1,298 @@ +=============================== +IBM 3270 Display System support +=============================== + +This file describes the driver that supports local channel attachment +of IBM 3270 devices. It consists of three sections: + + * Introduction + * Installation + * Operation + + +Introduction +============ + +This paper describes installing and operating 3270 devices under +Linux/390. A 3270 device is a block-mode rows-and-columns terminal of +which I'm sure hundreds of millions were sold by IBM and clonemakers +twenty and thirty years ago. + +You may have 3270s in-house and not know it. If you're using the +VM-ESA operating system, define a 3270 to your virtual machine by using +the command "DEF GRAF <hex-address>" This paper presumes you will be +defining four 3270s with the CP/CMS commands: + + - DEF GRAF 620 + - DEF GRAF 621 + - DEF GRAF 622 + - DEF GRAF 623 + +Your network connection from VM-ESA allows you to use x3270, tn3270, or +another 3270 emulator, started from an xterm window on your PC or +workstation. With the DEF GRAF command, an application such as xterm, +and this Linux-390 3270 driver, you have another way of talking to your +Linux box. + +This paper covers installation of the driver and operation of a +dialed-in x3270. + + +Installation +============ + +You install the driver by installing a patch, doing a kernel build, and +running the configuration script (config3270.sh, in this directory). + +WARNING: If you are using 3270 console support, you must rerun the +configuration script every time you change the console's address (perhaps +by using the condev= parameter in silo's /boot/parmfile). More precisely, +you should rerun the configuration script every time your set of 3270s, +including the console 3270, changes subchannel identifier relative to +one another. ReIPL as soon as possible after running the configuration +script and the resulting /tmp/mkdev3270. + +If you have chosen to make tub3270 a module, you add a line to a +configuration file under /etc/modprobe.d/. If you are working on a VM +virtual machine, you can use DEF GRAF to define virtual 3270 devices. + +You may generate both 3270 and 3215 console support, or one or the +other, or neither. If you generate both, the console type under VM is +not changed. Use #CP Q TERM to see what the current console type is. +Use #CP TERM CONMODE 3270 to change it to 3270. If you generate only +3270 console support, then the driver automatically converts your console +at boot time to a 3270 if it is a 3215. + +In brief, these are the steps: + + 1. Install the tub3270 patch + 2. (If a module) add a line to a file in `/etc/modprobe.d/*.conf` + 3. (If VM) define devices with DEF GRAF + 4. Reboot + 5. Configure + +To test that everything works, assuming VM and x3270, + + 1. Bring up an x3270 window. + 2. Use the DIAL command in that window. + 3. You should immediately see a Linux login screen. + +Here are the installation steps in detail: + + 1. The 3270 driver is a part of the official Linux kernel + source. Build a tree with the kernel source and any necessary + patches. Then do:: + + make oldconfig + (If you wish to disable 3215 console support, edit + .config; change CONFIG_TN3215's value to "n"; + and rerun "make oldconfig".) + make image + make modules + make modules_install + + 2. (Perform this step only if you have configured tub3270 as a + module.) Add a line to a file `/etc/modprobe.d/*.conf` to automatically + load the driver when it's needed. With this line added, you will see + login prompts appear on your 3270s as soon as boot is complete (or + with emulated 3270s, as soon as you dial into your vm guest using the + command "DIAL <vmguestname>"). Since the line-mode major number is + 227, the line to add should be:: + + alias char-major-227 tub3270 + + 3. Define graphic devices to your vm guest machine, if you + haven't already. Define them before you reboot (reipl): + + - DEFINE GRAF 620 + - DEFINE GRAF 621 + - DEFINE GRAF 622 + - DEFINE GRAF 623 + + 4. Reboot. The reboot process scans hardware devices, including + 3270s, and this enables the tub3270 driver once loaded to respond + correctly to the configuration requests of the next step. If + you have chosen 3270 console support, your console now behaves + as a 3270, not a 3215. + + 5. Run the 3270 configuration script config3270. It is + distributed in this same directory, Documentation/s390, as + config3270.sh. Inspect the output script it produces, + /tmp/mkdev3270, and then run that script. This will create the + necessary character special device files and make the necessary + changes to /etc/inittab. + + Then notify /sbin/init that /etc/inittab has changed, by issuing + the telinit command with the q operand:: + + cd Documentation/s390 + sh config3270.sh + sh /tmp/mkdev3270 + telinit q + + This should be sufficient for your first time. If your 3270 + configuration has changed and you're reusing config3270, you + should follow these steps:: + + Change 3270 configuration + Reboot + Run config3270 and /tmp/mkdev3270 + Reboot + +Here are the testing steps in detail: + + 1. Bring up an x3270 window, or use an actual hardware 3278 or + 3279, or use the 3270 emulator of your choice. You would be + running the emulator on your PC or workstation. You would use + the command, for example:: + + x3270 vm-esa-domain-name & + + if you wanted a 3278 Model 4 with 43 rows of 80 columns, the + default model number. The driver does not take advantage of + extended attributes. + + The screen you should now see contains a VM logo with input + lines near the bottom. Use TAB to move to the bottom line, + probably labeled "COMMAND ===>". + + 2. Use the DIAL command instead of the LOGIN command to connect + to one of the virtual 3270s you defined with the DEF GRAF + commands:: + + dial my-vm-guest-name + + 3. You should immediately see a login prompt from your + Linux-390 operating system. If that does not happen, you would + see instead the line "DIALED TO my-vm-guest-name 0620". + + To troubleshoot: do these things. + + A. Is the driver loaded? Use the lsmod command (no operands) + to find out. Probably it isn't. Try loading it manually, with + the command "insmod tub3270". Does that command give error + messages? Ha! There's your problem. + + B. Is the /etc/inittab file modified as in installation step 3 + above? Use the grep command to find out; for instance, issue + "grep 3270 /etc/inittab". Nothing found? There's your + problem! + + C. Are the device special files created, as in installation + step 2 above? Use the ls -l command to find out; for instance, + issue "ls -l /dev/3270/tty620". The output should start with the + letter "c" meaning character device and should contain "227, 1" + just to the left of the device name. No such file? no "c"? + Wrong major number? Wrong minor number? There's your + problem! + + D. Do you get the message:: + + "HCPDIA047E my-vm-guest-name 0620 does not exist"? + + If so, you must issue the command "DEF GRAF 620" from your VM + 3215 console and then reboot the system. + + + +OPERATION. +========== + +The driver defines three areas on the 3270 screen: the log area, the +input area, and the status area. + +The log area takes up all but the bottom two lines of the screen. The +driver writes terminal output to it, starting at the top line and going +down. When it fills, the status area changes from "Linux Running" to +"Linux More...". After a scrolling timeout of (default) 5 sec, the +screen clears and more output is written, from the top down. + +The input area extends from the beginning of the second-to-last screen +line to the start of the status area. You type commands in this area +and hit ENTER to execute them. + +The status area initializes to "Linux Running" to give you a warm +fuzzy feeling. When the log area fills up and output awaits, it +changes to "Linux More...". At this time you can do several things or +nothing. If you do nothing, the screen will clear in (default) 5 sec +and more output will appear. You may hit ENTER with nothing typed in +the input area to toggle between "Linux More..." and "Linux Holding", +which indicates no scrolling will occur. (If you hit ENTER with "Linux +Running" and nothing typed, the application receives a newline.) + +You may change the scrolling timeout value. For example, the following +command line:: + + echo scrolltime=60 > /proc/tty/driver/tty3270 + +changes the scrolling timeout value to 60 sec. Set scrolltime to 0 if +you wish to prevent scrolling entirely. + +Other things you may do when the log area fills up are: hit PA2 to +clear the log area and write more output to it, or hit CLEAR to clear +the log area and the input area and write more output to the log area. + +Some of the Program Function (PF) and Program Attention (PA) keys are +preassigned special functions. The ones that are not yield an alarm +when pressed. + +PA1 causes a SIGINT to the currently running application. You may do +the same thing from the input area, by typing "^C" and hitting ENTER. + +PA2 causes the log area to be cleared. If output awaits, it is then +written to the log area. + +PF3 causes an EOF to be received as input by the application. You may +cause an EOF also by typing "^D" and hitting ENTER. + +No PF key is preassigned to cause a job suspension, but you may cause a +job suspension by typing "^Z" and hitting ENTER. You may wish to +assign this function to a PF key. To make PF7 cause job suspension, +execute the command:: + + echo pf7=^z > /proc/tty/driver/tty3270 + +If the input you type does not end with the two characters "^n", the +driver appends a newline character and sends it to the tty driver; +otherwise the driver strips the "^n" and does not append a newline. +The IBM 3215 driver behaves similarly. + +Pf10 causes the most recent command to be retrieved from the tube's +command stack (default depth 20) and displayed in the input area. You +may hit PF10 again for the next-most-recent command, and so on. A +command is entered into the stack only when the input area is not made +invisible (such as for password entry) and it is not identical to the +current top entry. PF10 rotates backward through the command stack; +PF11 rotates forward. You may assign the backward function to any PF +key (or PA key, for that matter), say, PA3, with the command:: + + echo -e pa3=\\033k > /proc/tty/driver/tty3270 + +This assigns the string ESC-k to PA3. Similarly, the string ESC-j +performs the forward function. (Rationale: In bash with vi-mode line +editing, ESC-k and ESC-j retrieve backward and forward history. +Suggestions welcome.) + +Is a stack size of twenty commands not to your liking? Change it on +the fly. To change to saving the last 100 commands, execute the +command:: + + echo recallsize=100 > /proc/tty/driver/tty3270 + +Have a command you issue frequently? Assign it to a PF or PA key! Use +the command:: + + echo pf24="mkdir foobar; cd foobar" > /proc/tty/driver/tty3270 + +to execute the commands mkdir foobar and cd foobar immediately when you +hit PF24. Want to see the command line first, before you execute it? +Use the -n option of the echo command:: + + echo -n pf24="mkdir foo; cd foo" > /proc/tty/driver/tty3270 + + + +Happy testing! I welcome any and all comments about this document, the +driver, etc etc. + +Dick Hitt <rbh00@utsglobal.com> |