Tandy 1000RL HD

In some of my earliest articles I covered a few iterations of the popular Tandy 1000 line. The Tandy 1000A as well as the Tandy 1000HD and the compact Tandy 1000 EX and HX but now I’m going to shift to the end of the true Tandy 1000 line and talk about the Tandy 1000RL-HD the last of the 1000 line to be truly PCjr compatible.

As you can tell right away the 1000RL is a slim-line design and the machine is surprisingly light. You have a power button to the far right with a 720kb 3 1/2 floppy drive seated next to it. There is another bay for a second floppy drive but I don’t think a dual floppy RL version was ever sold, though I could be wrong. My model is the hard drive version which is slightly upgraded from the regular RL. You can tell easily which version your getting via the faceplate.

Both the RL and RL-HD come with a 8 bit IDE interface on the motherboard for a hard drive. This is the same style interface as found on machines like the Commodore Colt and in all honesty is not terribly useful. The drives are fairly uncommon and less then 40MB in size. My machine came with the original 20MB Seagate ST325X drive. The drive is very loud powering up and can be unreliable.

The HD version of the RL besides sporting a hard drive stock also has a battery-backed real time clock chip on the motherboard which the regular RL lacks.

The rear of the machine has two levels of ports.

On the far left we have a standard power port for a three prong power cord. Starting on the top left we have a serial port followed by two Tandy 1000 joystick ports, a stereo audio jack for speakers or headphones and a mic jack. Lastly on the top level we have a volume knob for the pc speaker which is a very nice addition. I think the knob would of been better placed on the front of the machine somewhere but its inclusion anywhere is always welcomed.

On the bottom row starting from the left we have a standard CGA port which will output CGA and of course Tandy Color Graphics or TGA as well as monochrome. The 25 pin printer port looks standard but unfortunately it supports no input so its basically a printer only port. Finally we have two ps/2 style ports. Now I say style because of the keyboard port. The mouse port is basically a ps/2 port and depending on the driver used you can get many ps/2 mice to work just fine. I was able to get a more modern ps/2 laser mouse working fine with Cutemouse drivers. The keyboard port though is not quite standard even though physically speaking it is ps/2 compatible. This machine requires an XT keyboard with a ps/2 style connector like the Tandy Enhanced Keyboard that came with this machine.

Otherwise you would need to find a XT keyboard and use an adaptor of some sort.

There is only one 8 bit ISA expansion port available on the rear of the machine making expansion very limited. On the question of adding video or sound cards, you may also of noticed the 1000RL lacks a composite port that was present on earlier Tandy 1000’s. Adding a CGA card with a composite out could be an answer to this issue though. On the sound card front keep in mind that using a Sound Blaster 1.0 or 2.0 may cause freezing under certain circumstances due to conflicts with devices using DMA 1.

The best option in my opinion for the expansion slot would be some kind of 8 bit IDE hard drive controller.

The case is relatively easy to remove and only requires the unscrewing of two screws.

The motherboard for the 1000RL is very compact. It’s basically a laptop sized board in a desktop case. This machine also has Tandy Deskmate and DOS 3.3 built into ROM so a hard drive is not needed to boot up and then access a floppy disk which is very nice.

Video – The video on the Tandy 1000RL uses an enhanced version of TGA known as ETGA which has all the old modes of the TGA plus a 640×200 with 16 color mode

1) Pc Speaker

 

2) riser card – this card contains the rear joystick ports, serial port and audio jacks as well as the volume knob. It is connected to the main board via a connector. The chip directly in front of the riser is I believe the PSSJ chip which controls the audio and ports on the riser.

 

 

3) CPU – the 1000RL CPU is an AMD 8086 running at 9.56mhz though there is an option in BIOS to set the speed to 4.77mhz or by typing “MODE SLOW” in Tandy DOS and “MODE FAST” to return to 9.56mhz. As I’ve mentioned before the 8086 in most circumstances performs faster then the 8088 at equivalent speed so some old game MAY have issues. This speed can be a benefit though for some games such as Digger that may run a little to slow on something like the PCjr. The CPU though is soldered onto the motherboard and not socketed thus it is impossible to replace it with a NEC V30 for more speed.

 

 

There is also no socket on the motherboard for a 8087 math co-pro but since hardly any games take advantage of one this isn’t much of an issue.

 

4) RAM – The standard RAM on the RL is 512kb but this can be expanded to 768kb (640 DOS, 128kb for video) via two 256k x 4 DRAM chips.

 

5) The regular 1000RL has a socket for an added real time clock but the RL-HD has one built into the motherboard using an easy to replace lithium coin battery.

 

6) One 8-bit ISA slot.

 

7) IDE-XT Interface – Both the RL and RL-HD have a IDE-XT 8-bit interface built into the motherboard. This interface only works with a small number of hard drives all being under 40MB.

 

8) Floppy Interface – The non standard floppy interface is typical of Tandy and supplies the power via the floppy cable to the drive.

 

9) PSU

 

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The Tandy 1000RL-HD has its problems. The built in HD interface was a dead end and there are some minor game incompatibilities but overall it makes a good Tandy machine. It supports TGA graphics as well as 3 channel audio sound and has a slow enough CPU to play most of the games that support those options just fine. Its also extremely light and small taking up little desk space. The fanless design means without a hard drive or when using a CF as a hard drive the machine is dead quiet and invites very little internal dust. The fact that DOS and Deskmate are present in ROM also alleviates some issues such as always needing a DOS boot disk handy to get into the system. They seem to be fairly common and reliable models so if you can find one for a low price its a no brainer to pick it up.